gvi mexico punta gruesa oct-dec 2010 annual report

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GVI Mexico Punta Gruesa Marine Expedition Mahahual Quarterly Report 104 Review: January 2008 - December 2010 1 © GVI – 2010 Page 1

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Page 1: GVI Mexico Punta Gruesa Oct-Dec 2010 Annual report

GVI Mexico

Punta Gruesa Marine Expedition

Mahahual

Quarterly Report 104

Review: January 2008 - December 2010

1© GVI – 2010 Page 1

Page 2: GVI Mexico Punta Gruesa Oct-Dec 2010 Annual report

GVI Mexico, Punta Gruesa Expedition Report 104

Submitted in whole to

GVIAmigos de Sian Ka’an

Comisión Nacional de Áreas Naturales Protegidas (CONANP)

Produced by

Laura McHugh – Science OfficerErin Lawrence – Base Manager

And

Genevieve Gammage Base Manager Faith Morrison Volunteer

Tristan Brown Science Officer James Broadway VolunteerDavid Blundell Field Staff Kelly Markowitz Volunteer

Oliver McGuinness Field Staff Kyle Antonchuk VolunteerRuaidhri Le Mage Field Staff Lisa Gagliano VolunteerRachel Budworth Scholar Maria Kroeger Volunteer

Joanna Richardson Scholar Mike Wood VolunteerDavid Sawyer NSP Maura Schonwald Volunteer

Carolina Ruiz Lozano NSP Catherine Daly VolunteerJames Wilderspin Volunteer Chad Brooks Volunteer

Gareth White Volunteer Carlita Foster-Hogg VolunteerMark Cowking Volunteer Alexander Gowan Volunteer

Brad Doyle Volunteer Samuel Stellmach VolunteerSarah Glanfield Volunteer Sebastien Languille VolunteerJennifer Jones Volunteer Daniel Benito Volunteer

Edited by

Stuart Fulton

GVI Mexico, Punta Gruesa

Email: [email protected] Web page: http://www.gvi.co.uk and http://www.gviusa.com

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Executive Summary The twelfth 10-week phase of the Punta Gruesa, Mexico, GVI expedition has now

been completed marking 3 years at the site. The expedition has maintained working

relationships with local communities through both English classes and local community

events. The expedition has continued to work towards the gathering of important

environmental scientific data whilst working with local, national and international partners.

The following projects have been run during Phase 104:

● Monitoring of strategic sites along the coast.

● Training of volunteers in the MBRS methodology including fish, hard coral, and

algae identification.

● Continuing the MBRS Synoptic Monitoring Programme (SMP) for the selected sites

within the Mahahual region to provide regional decision makers with up to date

information on the ecological condition of the reef.

● Providing English lessons and environmental education opportunities for the local

community.

● Further developing the current Marine Education programme for the children of

Mahahual that works alongside the standard curriculum.

● Liaising with local partners to develop a successful and feasible programme of

research in collaboration with GVI into the future.

● Contining to add to a coral and fish species list that will expand over time as a

comprehensive guide for the region.

● Continuation of the National Scholarship Programme, whereby GVI Punta Gruesa

accept a Mexican national on a scholarship basis into the expedition.

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Table of Contents

Executive SummaryTable of ContentsList of FiguresList of Tables1. Introduction2. Synoptic Monitoring Programme

2.1 Introduction2.2 Aims2.3 Methodology2.4 Results2.5 Discussion

3. Community Work Programme3.1 Introduction3.2 Objectives3.3 Activities and Achievements3.4 Review

4. Incidental Sightings Programme4.1 Introduction4.2 Aims4.3 Methodology4.4 Results4.5 Discussion

5. Marine Litter Monitoring Programme5.1 Introduction5.2 Aims5.3 Methodology5.4 Results5.5 Discussion

6. Bird Monitoring Programme6.1 Introduction6.2 Aims6.3 Methodology6.4 Results6.5 Discussion

7. Seagrass Monitoring Programme7.1 Introduction7.2 Aims7.3 Methodology7.4 Results7.5 Discussion

8. References9. Appendices

Appendix I – SMP Methodology OutlinesAppendix II - Adult Fish Indicator Species List

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Appendix III - Juvenile Fish Indicator Species ListAppendix IV - Coral Species ListAppendix V - Fish Species ListAppendix VI - Bird Species List

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List of Figures Figure 2-3-1 Map of the monitoring (yellow) and training (green) sites for GVI MahahualFigure 2-4-1 Percentage cover of hermatypic coral and macro algae by phaseFigure 2-4-2 Percentage Cover of Hermatypic Coral and Macro Algae by Site for Phase 104Figure 2-4-3 Percentage cover of hermatypic coral by site from phase 081-104Figure 2-4-4 Percentage cover of macroalgae by site from phase 081-104Figure 2-4-5 Deviation from Average Percentage (081-104) of Common Corals in 104Figure 2-4-6 Relationship between Dictyota and HalimedaFigure 2-4-7 Bleaching Occurrence 081-104Figure 2-4-8 Bleaching occurrence in Siderastrea siderea compared with bleaching occurrence

in other coral speciesFigure 2-4-9 Disease Occurrence 081-104Figure 2-4-10 Percentage of coral colonies with signs of diseaseFigure 2-4-11 Predation Occurrence 081-104Figure 2-4-12 Predation Index: Total number of predation events divided by number of colonies

monitored 081-104Figure 2-4-13 Adult fish recorded per transect across phasesFigure 2-4-14 Total adult fish biomass per phaseFigure 2-4-15 Average Percentage Abundance of Adult Fish by Family: Phases 081-104 Figure 2-4-16 Changes in adult fish family percentage abundance Figure 2-4-17 Percentage abundance of adult fish families per site during 104.Figure 2-4-18 Percentage abundance of juvenile fish families by phaseFigure 2-4-19 Percentage abundance of Acanthuridae and turf algae by phaseFigure 2-4-20 Density of Diadema antillarum and Stenopus hispidus recorded by phaseFigure 4-4-1 Sightings of common elasmobranch species per site visit 091-104Figure 4-4-2 Sightings of moray eels per site visit 091-104Figure 4-4-3 Turtle sightings per site visit 091-104Figure 4-4-4 Number of dolphin encounters per site visit from 091-104Figure 4-4-5 Number of S. barracuda sightings per site visit from 091-104Figure 4-4-6 Number of Lionfish Sightings per site visit 101-104Figure 4-4-7 Size distribution of lionfish recorded during phases 101-104Figure 5-1-1 Marine litter washed up on the beach at Punta GruesaFigure 5-3-1 Percentage of total weight by category for phase 104Figure 5-3-2 Average weekly weight of rubbish collected by phaseFigure 6-4-1 Composition of common bird species (30 or more sightings) in phase 104Figure 6-4-2 Composition of most common (average 5% or more) bird sightings as a percentage

across all phases (092-104)Figure 7-4-1 Average percentage cover of seagrass on seagrass transects during phase 102

and 104Figure 7-4-2 Average percentage cover of T. testudinum and S. filiforme on seagrass transects

during phase 102 and 104Figure 7-4-3 Average blade length of T. testudinum on seagrass transectsFigure 7-4-4 Relationship between T. testudinum blade length and predation during phase 102Figure 7-4-5 Relationship between T. testudinum blade length and predation during phase 104Figure 7-4-6 Average epiphyte cover on T. testudinum blades on seagrass transects during

phase 102 and 104

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List of Tables Table 2-3-1 Name, Site ID, Depth and GPS points of the monitoring sites.Table 2-4-1 Coral colonies monitored by CC at Punta GruesaTable 2-4-2 Number of transects and adult fish recorded per phaseTable 2-4-3 Number of transects/juvenile fish recorded per phaseTable 5-3-1 Marine litter collected as actual weight (kg) for phase 104Table 7-3-1 GPS positions for seagrass transects (Units in WGS 84 Format hddd.dddddo )

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1. Introduction The Mesoamerican Barrier Reef System (MBRS) extends from Isla Contoy at the North

of the Yucatan Peninsula, Mexico, to the Bay Islands of Honduras through Belize and

Guatemala and is the second largest barrier reef in the world.

The GVI Marine Programme within Mexico established its first base, Pez Maya, in the Sian

Ka’an Biosphere Reserve in 2003. Since then the programme has flourished, with a sister

site being set up to the south of the Biosphere near Mahahual. The current projects of GVI

Pez Maya and Punta Gruesa are assisting Amigos de Sian Ka’an (ASK) and Comisión

Nacional de Áreas Naturales Protegidas (CONANP) to obtain baseline data by conducting

marine surveys along the coast of Quintana Roo. By obtaining this data, ASK and its

partners can begin to focus on the areas needing immediate environmental regulation;

therefore, implementing management protection plans as and when required.

Such a project is especially significant in current times of rapid development along

the coast near the small fishing village of Mahahual area, due to the tourism industry

generated by the cruise ship pier that was built near the town in 2002.

The cruise ship pier was badly damaged following Hurricane Dean in August 2007 and

remained out of operation until October 2008 when Mahahual again began to receive

cruise ships. The current terminal can berth three cruise ships with, on average, seven

arrivals per week during high season. The cruise ships bring a flood of tourists into the

Mahahual region, an area that, at present, only has a limited infrastructure to deal with

large numbers of people. Furthermore, plans are underway to increase the number of

cruise ships in port and to develop the roadway through the mangrove system, increasing

access to vacation homes and hotels. There are also plans to re-open the small airport

about 5 km from Mahahual in an effort to get more people to the area. Such development

invites degradation of the ecosystems contributing to the health of the reef, as well as

activities directly disturbing the reef, such as wave runners and environmentally unaware

tourists, increasing the pressure on marine resources. Consequently, effective monitoring

is becoming ever more important. By assessing the health of the marine environment, new

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policies can be formulated and environmental degradation prevented if the appropriate

measures are taken to advocate long-term, sustainable ecotourism.

Punta Gruesa is located approximately 40 km north of Mahahual and 12 km south of

the southern tip of the Sian Ka´an Biosphere Reserve. The area is, at present, relatively

unpopulated although many plots of land in the locality are currently in the hands of foreign

investors to eventually be sold or are in the process of development.

This expedition is the fourth of GVI’s third year at Punta Gruesa. By using divers with

appropriate training, GVI has demonstrated how the local area can benefit from GVI’s

work. The data provided by large numbers of trained researchers will be extremely useful

for the decision makers for effective coastal zone management and provide a comparison

with data collected inside the Sian Ka´an Biosphere at Pez Maya.

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2. Synoptic Monitoring Programme

2.1 Introduction

The Synoptic Monitoring Programme looks to evaluate the overall health of the reef by

looking at three main areas: Benthic cover, fish populations and physical parameters.

Benthic Cover

Caribbean reefs were once dominated by hard coral, with huge Acropora palmata stands

on the reef crests and Acropora cervicornis and Montastraea annularis dominating the

fore reef. Today, many reefs in the Caribbean have been overrun by macroalgae during a

phase shift thought to have been brought about by numerous factors including a decrease

in herbivory from fishing and other pressures, eutrophication from land-based activities

and disease (McClanahan & Muthiga, 1998).

One of the Caribbean’s key reef herbivores, the long-spined sea urchin Diadema

antillarum, suffered mass mortality during 1983-84, resulting in a reduction in number

of approximately 90% (DeLoach, 1999). This has resulted in a large amount of grazing

pressure being removed, providing algae with an opportunity to increase in abundance.

Fishing pressures and the subsequent removal of herbivorous fish such as parrotfish has

further reduced grazers.

The main coral family in the Caribbean was once the Acroporidae which includes Acropora

cervicornis and A. palmata. In the mid 1980’s this family suffered a massive reduction in

abundance, which can be clearly seen on many sites in the area by the rubble of dead

skeletons of the above species. This decline has subsequently been attributed to both

White Band Disease and natural factors, and has led to A. palmata and A. cervicornis

being added to the US Endangered Species list as ‘threatened’ (NOAA, 2006). The

decline in the Acroporidae led to a change in dominance to the lesser reef building families

Poritidae and Agaricidae and it was found that sites across the Caribbean had decreased

in hard coral coverage by as much as 80% in last 30 years (Gardener et al., 2003). With

the reduction in Acropora sp., the decimation of the Diadema population and continued

fishing pressures, algal species have been able to flourish and, combined with increasing

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eutrophication, the shift to algal dominance has taken root.

Benthic transects record the abundance of all benthic species as well as looking at coral

health. The presence of coral on the reef is in itself an indicator of health, not only because

of the reefs’ current state, but also for its importance to fish populations (Spalding &

Jarvis, 2002). Coral health is not only impacted by increased nutrients and algal growth,

but by other factors, both naturally occurring and anthropogenically induced. A report

produced by the United Nations Environment Programme World Conservation Monitoring

Centre (UNEP-WCMC) in 2004 states that nearly 66% of Caribbean reefs are at risk from

anthropogenic activities, with over 40% of reefs at high to very high risk (UNEP-WCMC,

2006).

Naturally occurring events such as hurricanes can have devastating effects on coral reefs

in very short periods of time (Gardener et al., 2005). The impact of a hurricane can be felt

for some time after the initial strike due to increased sedimentation and nutrient load as

low turbidity and low nutrient levels are required for coral growth and health. An increase in

sedimentation has been found to increase mortality rates due to impeded photosynthesis

and increased energy required to remove sediment from colony surfaces (Nuges &

Roberts, 2003; Yentsch et al., 2002). Turbidity can increase after storms and hurricanes

and also as a result of anthropogenic activities such as deforestation, dredging and coastal

construction. Hurricanes can also damage reefs through increased wave action, which

physically destroys more fragile species.

Different coral families have differing resistances to stress. However, with multiple

stressors present (sediment, removal of herbivores, disease) even the most hardy

can succumb to the pressure, resulting in loss of coral coverage (Kenyon et al., 2006;

Yentsch et al., 2002). The measurement of percentage coral mortality provides a way of

determining the state of health for the colony and these measures are taken during benthic

monitoring (Nuges & Roberts, 2003).

As a result of the phase shift on Caribbean reefs, the abundance and type of algae present

are of particular interest. It has been found that some macroalgae and cyanobacteria do

not simply occupy space on the reef, but can actively inhibit coral recruitment (Kuffner et

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al., 2006). Of those algae present on the reef, two key genera are particularly observed,

Halimeda and Dictyota. Halimeda is an important genus due to its calcified structure

providing large amounts of calcium carbonate that contributes greatly to beaches and adds

to the structure of the reef (Littler et al., 1989). Dictyota sp. have been found to not only

inhibit the growth of Halimeda sp. through its epiphytic nature, but also certain species

have been found to be able to kill coral recruits in ways other than by simply shading the

light or taking the available space (Beach et al., 2003; Kuffner et al., 2006). Due to their

opportunistic nature, ability to deal with stress and mechanisms for out-competing coral for

space, algae has been able to maintain the coral-algae phase shift.

The major driver behind the phase shift has not been confirmed, but it is believed that the

reversal of one or more causative factors could lead to a shift back to coral dominance

(Edmunds & Carpenter, 2001). In the Caribbean the decrease in coral coverage is

believed to be slowing (Gardener et al., 2003). Studies in Jamaica have found areas of

Diadema resurgence and within these areas, macroalgae coverage has been found to

have reduced and the number of young corals has increased (Edmunds & Carpenter,

2001).

Through monitoring the abundances of hard corals, algae and various other key benthic

species, as well as numbers of Diadema urchin encountered, we aim to determine not only

the current health of the local reefs but also to track any shifts in phase state over time.

Fish Populations

Large numbers of fish can be found on and around coral reefs. These fish are associated

with the reef for a variety of reasons. The structural complexity of coral reefs provides

shelter for fish, a quick refuge from predators during the day or a safe place to sleep at

night. Others rely on the reef directly for food, be they corallivores, such as Butterflyfish

(Chaetodontidae) or territorial herbivores like some Damselfish (Pomacentridae). The

reef also indirectly provides food for predatory fish, both those that are site attached like

Scorpionfish and pelagic predators such as Jacks.

Fish surveys are focused on specific species (see Appendix II) that play an important role

in the ecology of the reef as herbivores, carnivores, commercially important fish or those

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likely to be affected by human activities (AGRRA, 2000).

The most important herbivorous fish on the reef are the Parrotfish (Scaridae) and the

Surgeonfish (Acanthuridae) (AGRRA, 2000).

Parrotfish feed primarily on uncalcified algae and seagrasses. However, they are more

widely known for scraping algal turf from dead coral heads with their fused front teeth,

which form a beak-like structure. Live coral is rarely eaten by parrotfish, with the exception

of the Stoplight Parrotfish Sparisoma viride, and the Queen Parrotfish, Scarus vetula,

which often feed on living Montastraea annularis colonies. Parrotfish also utilise the caves,

overhangs and crevices in the reef for protection at night from predators (DeLoach, 1999).

Acanthuridae regularly feed in large mixed aggregations on the reef, descending upon

damselfish gardens and decimating them before moving on. Feeding continues all day,

with Blue Tangs and Doctorfish concentrating their activities on the reef itself, while the

Ocean Surgeonfish tend to forage over the sand. All surgeonfish play an important role in

limiting the growth of algae on the reef (DeLoach, 1999).

The importance of other fish can be determined by commercial fishing pressure. Many

carnivores on the reef such as Groupers and Snappers are important predators and

their presence denotes a balanced food chain and low levels of fishing. Snappers

feed nocturnally on crustaceans and small fish and inhabit the reef in daylight hours.

Groupers occasionally feed during the day, but mainly at dusk and dawn, preying on fish,

crustaceans and cephalopods (DeLoach, 1999).

Unlike the groupers and snappers, Jacks and Barracuda are pelagic predators and

are considered top-level carnivores feeding mainly on fish. They are also commercially

important fish and their removal has knock-on effects to the balance of the food chain

(DeLoach, 1999).

Other predatory fish recorded during fish surveys and which are susceptible to fishing

pressures are the many Grunt species, often the most abundant fish on many Caribbean

reefs, which spend their days around the reef, feeding at night on sea grass beds, Hogfish,

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a favourite target for spear fishers, Spanish Hogfish and Triggerfish (Lee & Dooley, 1998;

DeLoach, 1999).

Fish such as Butterflyfish and Angelfish are also commercially important, but for removal

for the aquarium trade rather than for commercial fishing. Butterflyfish are coralivores,

eating polyps from both hard corals and gorgonians and are considered to be a general

indicator of good coral health. Angelfish, once thought to belong to the same family as

the Butterflyfish, can also be coralivores, but have evolved over time to feed on sponges,

possibly to avoid increased competition for food (AGRRA, 2000 & DeLoach, 1999).

All reef fish play an important role in maintaining the health and balance of a reef

community. Fishing typically removes larger predatory fish from the reef, which not only

alters the size structure of the reef fish communities, but with the reduction in predation

pressure, the abundance of fish further down the food chain is now determined through

competition for resources (AGRRA, 2000).

Although each fish is important, the removal of herbivores can have a considerable impact

on the health of the reef, particularly in an algal dominated state, which without their

presence has little chance of returning to coral dominance. Through the monitoring of

these fish and by estimating their size, the current condition of the reef at each site can

be assessed, any trends or changes can be tracked and improvements or deteriorations

determined.

Population abundances are determined to an extent by larval recruitment. The vast

majority of reef fish are pelagic spawners, releasing their gametes into the water column

where they are under the influence of water flow for several weeks. Other forms of

spawning include benthic egg-laying, which is common among Damselfish and Triggerfish.

Despite the fertilised eggs being laid in nests and protected by diligent parents, once

hatched, even these larvae have a pelagic period where their distribution is also controlled

by water movement. During this time the fish larvae can travel hundreds of miles from

where they were originally spawned, occasionally, however, due to specific oceanographic

influences, larvae may be held close to their site of origin (DeLoach, 1999).

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For larvae which survive their pelagic existence, when they eventually settle, they may be

a considerable distance from where they were spawned. Recruitment of these larvae into

the populations of the different sites has been found to vary. There are several theories

about the difference in recruitment levels between sites, even those which are closely

situated. Some believe that each reef has a specific carrying capacity and recruitment is

based on existing adult abundances. Others believe that abundance of larval recruits is

determined after they have settled on a site when competition for resources such as food,

space and shelter begin. Rates of predation at specific sites will also play their part in the

survival of larval recruits. Recruitment has also been found to vary seasonally (DeLoach,

1999).

The monitoring of juvenile fish concentrates on a few specific species. The presence

and number of larvae at different sites can be used as an indication of potential future

population size and diversity. Due to the extensive distribution of larvae, however,

numbers cannot be used to determine the spawning potential of a specific reef. The

removal of fish from a population as a result of fishing, however, may influence spawning

potential and affect larval recruitment on far away reefs. The removal of juvenile predators

through fishing may also alter the number of recruits surviving to spawn themselves

(AGRRA, 2000).

Together with the information collected on adult fish, a balanced picture of the reef fish

communities at different sites can be obtained.

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Physical Parameters

For the optimum health and growth of coral communities certain factors need to remain

relatively stable. Measurements of turbidity, water temperature, salinity, cloud cover,

and sea state are taken during survey dives. Temperature increases or decreases can

negatively influence coral health and survival. As different species have different optimum

temperature ranges, changes can also influence species richness. Corals also require

clear waters to allow for optimum photosynthesis. The turbidity of the water can be

influenced by weather, storms or high winds stirring up the sediment, or anthropogenic

activities such as deforestation and coastal construction. Increased turbidity reduces light

levels and can result in stress to the coral. Any increase in coral stress levels can result in

them becoming susceptible to disease or result in a bleaching event.

In the near future, GVI Punta Gruesa hopes to be able to use this data for analysis of

temporal and seasonal changes and try to correlate any coral health issues with sudden or

prolonged irregularities within these physical parameters.

2.2 Aims

The projects at Punta Gruesa and Pez Maya aim to identify coral and fish species with

a long term, continuous dataset allowing changes in the ecosystem to be identified. The

projects also aim to ascertain areas of high species diversity and abundance. The data is

then supplied to the project partners who can use the data to support management plans

for the area.

2.3 Methodology

The methods employed for the underwater visual census work are those outlined in the

MBRS manual (Almada-Villela et al., 2003), but to summarize, GVI use three separate

methods for buddy pairs:

Buddy method 1: Surveys of corals, algae and other sessile organisms

Buddy method 2: Belt transect counts for coral reef fish

Buddy Method 3: Coral Rover and Fish Rover diver

The separate buddy pair systems are outlined in detail in Appendix I.

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The sites that are monitored as part of the MBRS programme at GVI Punta Gruesa were

chosen through discussions with ASK, the Programa de Manejo Integrado de Recursos

Costeros (MIRC, a subsidiary of UQROO) and discussions with local fishermen.

The established sites currently cover the immediate vicinity at Punta Gruesa but more

sites are looking to be added to the monitoring programme. Seven of these have been

monitored annually and two more were added in 2009, with a range covering 6.5 km of the

coast (see Figure 2-3-1, Table 2-3-1).

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Figure 2-3-1 Map of the monitoring (yellow) and training (green) sites for GVI Punta Gruesa

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Location Site ID Depth Latitude LongitudeLos Bollos LB10 10m 19.02 21.8 087.33 54.8Las Joyas LJ10 10m 19.01 53.0 087.34 07.6Los Milagros LM10 10m 19.01 35.6 087.34 13.3Costa Norte CN10 10m 19.01 31.0 087.34 16.5Las Delicias LD10 10m 19.01 24.7 087.34 20.2Las Palapas LP10 10m 19.01 55.8 087.34 05.0Flor de Cañón FDC10 10m 19.02 04.4 087.34 03.4Sol Naciente SN10 10m 19.00 36.0 087.34 33.0Los Gorditos LG25 25m 18.59 37.6 087.34 51.9

Table 2-3-1 GPS locations of the monitoring sites. GPS points are listed here in the WGS84 datum

The eight sites at 10m are situated on the reef crest with one deeper site “Los Gorditos”,

which offers a wide sample area with spur and groove formations, in comparison to the

wall at the other sites.

2.4 Results Benthic Cover

During Phase 104, data was collected from seven of the nine monitoring sites. Due to

unfavourable weather conditions it was not possible to complete LB10 or LG25.

A key objective of the coral monitoring programme at Punta Gruesa is the monitoring of

the coverage of, and relationship between, coral and algae. Point Intercept monitoring

in Phase 104 calculated an average coral coverage of 10.43%. This is very similar to

the values calculated for both 102 and 103 (10.45% and 10.66% respectively). The

percentage of coral cover has remained relatively stable since the survey began here in

2008; ranging from 7.62% during 093 to 11.55% during 092. The overall average for the

whole of the survey period is 9.76%.

Algal coverage decreased from 69.68% in Phase 103 to 60.86% in Phase 104. This is the

second lowest value on record. Since monitoring began, algal coverage has varied from

60.10% in 084 to 72.96% in 093 with the overall average for the whole of the survey period

being 67.73%. It is interesting to note that the three lowest average values on record all

occur during the fourth phase of each year.

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Figure 2-4-1 Percentage cover of hermatypic coral and macroalgae by phase

LJ10 had the highest coral coverage this phase with 19.83% (Figure 2-4-2), whilst FDC10

had the lowest with 5.50%. Over time, the site with the lowest coral cover has alternated

between FDC10 and LD10 (Figure 2-4-12).

Figure 2-4-2 Percentage Cover of Hermatypic Coral and Macro Algae by Site for Phase 104

Average algal coverage has varied hugely since monitoring began. Once again there is a

lot of variation within each site between phases (Figure 2-4-4).

Figure 2-4-3 Percentage cover of hermatypic coral by site from phase 081-104Black line indicates average across all sites

Figure 2-4-4 Percentage cover of macroalgae by site from Phase 081-104Black line indicates average across all sites

This phase has seen higher than average observations for Agaricia agaricites, Meandrina

meandrites, and Siderastrea siderea when compared with the 2008-2010 average coral

percentage cover (Figure 2-4-5). Agaricia agaricites has shown levels furthest above the

average. This phase has seen lower than average observations of Dichocoenia stokesi,

Diploria strigosa, Montastraea annularis, Montastraea cavernosa, Montastraea faveolata

and Porites astreoides. Diploria strigosa has shown levels furthest below average.

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Figure 2-4-5 Deviation from Average Percentage (081-104) of Common Corals in 104

Previous GVI Phase Reports from the old base in Mahahual have shown an inverse

relationship between Dictyota sp. and Halimeda sp. (GVI Mahahual 074). The data

from the new Punta Gruesa base does not show this relationship very clearly, although

percentage cover of Halimeda sp. tends to peak around the second phase of each year,

whereas the percentage cover of Dictyota sp. tends to be at its lowest during this phase of

the year. (Figure 2-4-6).

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Figure 2-4-6 Relationship between Dictyota and Halimeda Coral Diseases, Predation and Bleaching

During Phase 104, 679 corals were assessed as part of the Coral Communities survey.

There have been previous phases that included more corals but this phase, the number of

corals assessed per transect was relatively high in comparison to previous phases.

Phase 081 082 083 084 091 092 093 094 101 102 103 104Transects 21 32 35 34 39 30 45 45 45 35 44 35Colonies 410 558 523 517 542 554 767 831 684 632 771 679

Table 2-4-1 Coral colonies monitored by CC at Punta Gruesa

During Phase 104 there were 112 recorded instances of bleaching, including nine of partial

bleaching. No full bleaching was recorded. The total bleaching occurrence in all corals is

equal to 16.49% of corals surveyed (Figure 2-4-8). This is the lowest level of bleaching

recorded at Punta Gruesa.

Siderastrea siderea is often found to be pale bleached and has therefore been separated

from the other corals so as not to bias the results and obscure any bleaching patterns

in other corals. There has been a dramatic decrease in the bleaching occurrence in

Siderastrea siderea colonies during Phase 104 (Figure 2-4-8). This is the lowest level of

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bleaching recorded in this species.

There has also been a decrease in bleaching occurrence in other coral species although to

a lesser extent. Bleaching decreased from 27.89% in Phase 103 to 7.92% in Phase 104.

This is also the lowest level of bleaching recorded since the survey began.

Bleaching this year peaked in the third phase, 103, which is a little earlier than in previous

years. In 2008 and in 2009 bleaching peaked in the fourth phase. This pattern is not true of

Siderestrea siderea however, which showed its highest levels of bleaching in Phases 081,

092 and 103.

Figure 2-4-7. Bleaching Occurrence 081-104

Figure 2-4-8 Bleaching occurrence in Siderastrea siderea compared with bleaching occurrence in other coral species

Dark-spot disease remains the most common disease sighted (Figure 2-4-9) and red-

band disease was the only target disease not recorded in 104. This is in stark contrast

to Phase 103 when it was recorded on 31 different colonies. Overall, the percentage of

diseased colonies remains low at 7.81% but this is still the third highest value recorded.

There has been a steady increase in disease occurrence since monitoring began

(Figure 2-4-10). Incidence of disease was recorded over a wide variety of coral genus.

Agaricia, Dichocoenia, Diploria, Helioceris, Meandrina, Montastraea, Siderastrea and

Stephanocoenia were all affected, and in some genus, Montastraea in particular, multiple

species showed multiple diseases to be present.

Figure 2-4-9 Disease Occurrence 081-104

Figure 2-4-10 Percentage of coral colonies with signs of disease

The most common type of predation was sponge predation (Figure 2-4-11), which affected

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51 colonies, followed by gorgonian predation, which affected 11. Sponge predation has

been the most common type of predation recorded every. The only types of predation not

recorded this phase were short coral snail and fireworm.

Figure 2-4-11 Predation Occurrence 081-104

In total there were 79 instances of predation recorded out of the 679 corals that were

monitored. Figure 2-4-12 shows a predation index to compare the amount of predation

seen with that seen in previous phases. The amount of predation recorded has increased

dramatically since Phase 094, peaking during Phase 102. Since then, predation levels

have dropped but are still much higher than they were between 081 and 094.

Figure 2-4-12 Predation Index: Total number of predation events divided by number of colonies monitored 081-104

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Fish Populations

A total of 64 transects recording target adult and juvenile fish species were completed

in Phase 104, eight at each monitoring site. Los Gorditos was the only site that was not

completed.

A total of 879 individuals from 30 species were recorded in Phase 104, an average of

13.73 per transect. The number of adults per transect recorded appears to gradually

increase across phases but with considerable variation (Figure 2-4-13).

Phase Transects per phase

Total target adult fish in phase

Av. fish per transect

No. of species

081 30 391 13.03 31082 54 649 12.02 33083 49 280 5.71 27084 40 321 8.03 28091 39 328 8.41 29092 48 843 17.56 36093 72 809 11.24 38094 72 1282 17.81 38101 72 1264 17.56 40102 56 1050 18.75 31103 72 792 11.00 33104 64 879 13.73 30

Table 2-4-2 Number of transects and adult fish recorded per phase.

Figure 2-4-13 Adult fish recorded per transect across phases

Adult fish biomass is estimated using a weighting system for each size category and

species (Froese & Pauly, 2006, figures obtained from table constructed by A. Cameron).

Total biomass of all target adult fish species in 104 was calculated to be 4.59 kg 100 m-2

(Figure 2-4-14). This brings the average biomass for our study area to 3.93 kg 100 m-2.

Figure 2-4-14 Total adult fish biomass per phase

Following previous trends, the Haemulidae was the most commonly recorded family in

Phase 104 (Figure 2-4-15), with 63.52% of the total number observed, an increase from

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previous phases. The second most abundant family was the Acanthuridae with 15.11%,

the lowest value recorded for this family since Phase 094. The next two most abundant

families were Scaridae and Serranidae, which is consistent with data from previous

phases. Sphyraenidae (Great Barracuda) are rarely recorded in transects in any phase,

although they have been observed outside of transects (see Incidental Sightings).

Figure 2-4-15 Average Percentage Abundance of Adult Fish by Family: Phases 081-104

Haemulidae have been the most abundant family every phase and their abundance is

increasing. In previous phases it was noted that the two dominant families, Haemulidae

and Acanthuridae, appeared to be showing a link in abundance: where one increased the

other decreased and vice versa. This pattern has continued this phase. The percentage

abundances of Pomacanthidae and Pomacentridae increased and decreased in sync with

each other between Phases 082 and 102 but this pattern has not continued since then.

Balistidae and Monacanthidae are grouped together. The percentage abundance of this

collective group declined dramatically between 081-091 but since then numbers have

increased slightly and remained relatively stable.

Figure 2-4-16 Changes in adult fish family percentage abundance

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The grunts (Haemulidae) were the most abundant family observed at all of the sites

monitored except FDC10 (Figure 2-4-16). At FDC10 the most abundant family was the

Acanthuridae, which made up 35.4% of the fish recorded, followed by the Haemulidae

at 26.8%. This is similar to the findings from 103 when Acanthuridae was also the most

abundant family at FDC10 making up 37.8% of the fish recorded, followed by Haemulidae

with 30.5% (see previous Phase reports). Acanthuridae were the second most abundant

family across most sites during 104, with the exception of LJ10 where Serranidae were the

second most abundant and LM10 where Acanthuridae and Serranidae were joint second

in abundance.

Figure 2-4-17 Percentage abundance of adult fish families per site during 104.

Juvenile Fish

A total of 495 juveniles were recorded in the 64 transects completed, an average of 7.73

per transect. Across the three years of data collection, juvenile numbers seem to be higher

in the second and third phases of the year and lowest during the first phase of the year.

Phase Transects per phase Total juvenile fish in phase

Av. Juvenile fish per transect

081 30 302 10.07082 54 815 15.09083 49 606 12.37084 40 308 7.70091 39 224 5.74092 48 862 17.96093 72 2150 29.86094 72 570 7.92101 72 437 6.07102 56 1211 21.63103 72 1145 15.90

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104 64 495 7.73

Table 2-4-3 Number of transects/juvenile fish recorded per phase

Stegastes partitus is, on average, the most abundant juvenile species recorded and

numbers are lowest during the fourth phase each year, however, the next three most

abundant species all tend to be lowest in numbers during the first phase each year. The

three lowest abundances for Halichoeres garnoti and for Sparisoma aurofrenatum were

all from the first phases of the year, and two of the three lowest abundances of Stegastes

partitus were also in the first phase of the year. This could explain the annual cyclical

pattern observed in juvenile fish abundance.

As with previous phases a total of six juvenile fish families were recorded on transects

in 104. The most abundant family was Labridae, which made up 40.81% of recorded

juveniles. This is consistent with data from previous phases. Looking at Figure 2-

4-18 there appears to be some link in percentage abundance between Labridae

and Pomacentridae juveniles, with one decreasing as the other increases. Scaridae

abundance is quite variable; their numbers seem to peak during the fourth phase of each

year. Acanthuridae, Chaetodontidae and Grammatidae juvenile numbers on the reef

remain low across all phases.

Figure 2-4-18 Percentage abundance of juvenile fish families by phase

Acanthuridae and turf algae show some positive correlation (Pearson’s r = 0.75) (Figure 2-

4-19), however the apparent close link during 2008 did not appear to be as close in 2009

or 2010. A sharp decrease has been observed in both Acanthuridae and turf algae this

phase.

Figure 2-4-19 Percentage abundance of Acanthuridae and turf algae by phase

Stenopus hispidus and Diadema antillarum

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Surveys of banded coral shrimp (Stenopus hispidus) and long-spined sea urchins

(Diadema antillarum) taken during the juvenile fish transects recorded very few sightings.

3 Diadema antillarum were recorded this phase giving a density of 0.00156 individuals per

m2 and an average density of 0.00131 individuals per m2 across all phases. 6 Stenopus

hispidus were recorded this phase giving a density of 0.00313 individuals per m2 during

and an average density of 0.00416 individuals per m2 across all phases.

Figure 2-4-20 Density of Diadema antillarum and Stenopus hispidus recorded by phase

2.5 Discussion

Benthic Cover

Coral cover on reefs across the Caribbean has decreased dramatically over the past three

decades from about 50% to 10% cover (Gardner et al., 2003). Although the coral cover

at Punta Gruesa is undoubtedly lower than it has been in the past, it is in line with other

values calculated for this region. The percentage coral cover for Phase 104 was 10.43%,

with the average over all phases being 9.76%. This percentage of coral cover is slightly

below the regional average of 11% but is above the Mexico Yucatan average of 7.5%

(Wilkinson, 2008).

The macroalgae cover is dramatically higher than the regional average of 18% and the

Mexico Yucatan average of 14.9% (Wilkinson, 2008). AGRRA (2005) states that the

average macroalgae cover for the Mesoamerican Reef is 25% and the Caribbean average

is 34%. There is a certain degree of variation between these figures but, regardless of

which is “correct”, the values calculated at Punta Gruesa are consistently significantly

higher. Rogers & Miller (2006) found that when new substrate was made available in one

Caribbean site following a severe hurricane, algae colonized the newly available substrate

and, once established, slowed or prevented new coral colonization. Hurricane Dean was a

powerful Category 5 Hurricane that made land fall in Mahahual in August 2007 (Franklin,

2008), so it is possible that this may be the reason for the high macroalgae cover in this

region.

The three lowest average values of macroalgae cover at Punta Gruesa all occur during

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the fourth phase of each year. Dawes et al. (1974) carried out studies on three species

of macroalgae (Eucheuma sp.) in Florida and found that they exhibited peak rates of

growth in the spring and lower rates of growth in the summer/fall. These lower summer

growth rates were due to high temperatures, increased light intensities and a decrease

in available nutrients. The monitoring during the fourth phase of each year occurred after

these low rates of growth and before peak growth rates in spring and so could explain the

observed pattern.

Previous GVI Phase Reports have shown an inverse relationship between Dictyota sp.

and Halimeda sp. (GVI Mahahual 074). Calcified green algae, particularly Halimeda sp.

are especially important as the predominant contributors to the production of marine

sediments (Littler et al., 1989). A study by Beach et al. (2003), on another reef (Florida)

concluded that epiphytic Dictyota sp. have a negative impact on Halimeda sp. resulting

in a significantly slower rate of growth. Their work indicated that epiphytic Dictyota

negatively impacts metabolic rates of Halimeda tuna, in part by shading, and also through

a chemically mediated process. The relationship between Halimeda sp. and Dictyota sp.

has not been demonstrated very clearly in recent years at Punta Gruesa. This could be

due to the presence of the non-epiphytic form of Dictyota sp., as this has limited affects on

Halimeda sp. (Beach et al., 2003).

Coral Diseases, Predation and Bleaching

During Phase 104, 16.49% of corals were recorded as suffering from some sort of

bleaching and there were no recorded instances of full bleaches. This is the lowest value

recorded since monitoring began in 2008. This is the case for both Siderastrea siderea,

which is often found to be bleached, and for the other coral species as well. Bleaching in

2010 peaked in the Phase 103, slightly earlier than in 2008 and 2009 when it peaked in

the fourth phase. Studies have recorded that temperature increases of 1°C above average

for a sustained period (i.e. a month) can cause mass bleaching (Hoegh-Guldberg, 1999).

This can also be amplified by calm seas, allowing more photosynthetically active radiation

to penetrate the surface waters (Sheppard et al., 2009). This would explain the (roughly)

annual pattern that has been observed here since 2008. NOAA (2010) observed that,

since March 2010, monthly sea-surface temperature averaged over the whole of the main

cyclone development region (which includes the Caribbean Sea and tropical Atlantic

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Ocean) have been at record levels. These high temperatures early in the season could

have caused an early peak in levels of bleaching. The extremely low levels of bleaching

recorded during Phase 104 are difficult to explain given that sea temperatures were

predicted to be at record levels throughout most of 2010.

Dark spot disease remains the most common disease recorded. This disease is most

commonly observed on Siderastrea siderea (Humann & DeLoach 2008), which may

explain why the disease is recorded with such frequency. Siderastrea siderea is the most

common coral recorded, making up 30% of the corals recorded during Phase 104. There

has been a steady increase in disease occurrence since monitoring began at Punta

Gruesa. Rosenberg & Ben-Haim (2002) compiled a review of microbial diseases in corals

in which they concluded that diseases of corals have increased dramatically during the

last few decades. They stated that outbreaks of these diseases are highly correlated with

increases in sea-water temperature and went on to say that in the twentieth century, there

was an average worldwide 1˚C rise in temperature, the largest in more than 1000 years.

As mentioned above, NOAA (2010) observed that 2010 has been a record year for sea

surface temperature. These conditions were expected to persist through August-October.

Sponge predation has been the most common type of predation recorded each phase, and

showed a huge peak in occurrence during Phase 102. Overall there has been an increase

in levels of predation. This trend is still evident when sponge predation data is excluded.

The reasons behind this increase in predation and overgrowth events are unknown.

Fish Populations

The number of adults recorded was slightly higher during Phase 104 than during 103,

13.73 fish per transect compared with 11.00 fish per transect respectively. The number

of adults recorded per transect appears to have gradually increased across phases but

with considerable variation. This is mostly due to an increase in Haemulidae, the dominant

family, which makes up an average of 50% of the fish recorded. The reason for their

apparent increase in abundance here is unknown.

Total biomass of all target adult fish species in Phase 104 was calculated at 4.59 kg 100

m-2, bringing the average biomass for our study area to 3.93 kg 100 m-2. Both of these

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values are lower than the biomass calculated for the Mesoamerican region, which is 4.98

kg 100 m-2, but are higher than the biomass calculated for the Mexico Yucatan region,

which is 3.03 kg 100 m-2 (Wilkinson, 2008). It is worth bearing in mind though, that the

biomass calculated at Punta Gruesa is calculated using target fish species only, whereas

the figures given above may include additional species.

In the report for Phase 101 it was mentioned that surveyor error in sizing estimates

may have biased the data for 094. Although training is rigorous and volunteers must

show consistently high accuracy in identification and sizing estimates prior to beginning

monitoring, there will always be some degree of human error in data collection, particularly

in size estimates done by eye. Studies suggest that visual sizing by non-specialist divers

will achieve 80% accuracy by the third trial (Darwall & Dulvy, 1996), and that this is not

significantly different from observations by experienced observers. Without recourse to

expensive recording equipment, error in this area is as minimised as practically possible.

Following previous trends, the Haemulidae was the most abundant family in Phase 104,

making up 63.52% of the total number observed, an increase from previous phases.

Haemulidae often make up the largest biomass on reefs in continental or insular shelf

areas that have large expanses of grass beds and sand flats (Human & DeLoach, 2008).

In previous phases it was noted that the two dominant families, Haemulidae and

Acanthuridae, appeared to be showing an inverse link in abundance: where one

increased the other decreased and vice versa. This pattern has continued this phase. As

these families occupy differing niches within the coral reef ecosystem, it is unlikely that

populations should have a direct effect on one another. Acanthuridae feed throughout

the day on a wide variety of plants on the reef (DeLoach, 1999), while most Haemulidae

are carnivores feeding nocturnally on crustaceans in the sand flats and seagrass beds

(Humann & DeLoach, 2008). This habitat preference may explain why both species are

less frequently recorded on the deeper site LG than at the shallower reef crest sites with

easier access to feeding grounds (see previous reports from Punta Gruesa).

The percentage abundances of Pomacanthidae and Pomacentridae (represented only by

the yellowtail damselfish, Microspathadon chrysurus) increased and decreased in sync

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with each other between Phases 082 and 102 but this pattern has not continued since

then. These two families also occupy different niches within the coral reef ecosystem

so, once again, it is unlikely that their populations should have a direct affect on each

other. Pomacanthidae are sponge-eating species. The tissue from a wide variety of

sponges making up 95% of the food consumed by species in the genus Holacanthus, and

70% in the genus Pomacanthus. Microspathadon chrysurus, however, farm and defend

permanent territories of filamentous algae that surround their centrally-located hiding holes

(DeLoach, 1999).

Throughout the three years of data collection, juvenile numbers have exhibited a cyclic

pattern, with abundance being greatest in the second and third phases of the year and

lowest during the first phase of the year. This pattern is mostly driven by abundance of

Stegastes partitus (Bicolor damselfish), Thalassoma bifasciatum (Bluehead wrasse),

Sparisoma aurofrenatum (Redband parrotfish) and Halichoeres garnoti (Yellowhead

wrasse) all of which are recorded in great numbers each year at Punta Gruesa and all of

which are highest in numbers during the second and third phases. These results can be

explained by spawning cycles. Although many species settle randomly throughout the

year, recruitment reaches its peak in the summer (DeLoach, 1999).

The most abundant juvenile family recorded was Labridae, which made up 40.81% of

juveniles recorded this phase. This is consistent with data from previous phases. This is

partly due to the fact that there are six different species within this family that are recorded,

but is also due to the very high numbers of Thalassoma bifasciatum and Halichoeres

garnoti.

There appears to be some link in percentage abundance between Labridae and

Pomacentridae juveniles, with one decreasing as the other increases. This may be the

result of spawning cycles. Scaridae abundance is quite variable; their numbers seem to

peak during the fourth phase of each year.

Acanthuridae and turf algae show some positive correlation, however the apparent close

link during 2008 did not appear to be so close in 2009 or 2010. This is the second most

abundant family on the reef, making up over 15% of the fish recorded during Phase 104,

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and given their preference for turf algae, it would be expected that there would be a close

correlation between the abundance of turf and the Acanthuridae. Such a correlation

may be considered to be indicative of a balanced equilibrium within the reef ecosystem;

however an increased abundance of Acanthuridae might also indicate a phase shift to an

algae-dominated reef. Although Acanthuridae abundance is relatively high, overall their

abundance does not appear to be increasing across the survey time.

Stenopus hispidus and Diadema antillarum

Diadema antillarum is an important functional grazer of algae on coral reefs that was

largely wiped out by an unknown pathogen in the Caribbean during 1983-84 (Reid et al.,

2009). The population has since been reported as making a slow comeback (Humann

& DeLoach, 2002), however at 0.00156 individuals per m2 this does not appear to be

the case in this region. This density is much lower than the Mesoamerican Barrier Reef

average, which is 0.03 per m2, and is also much lower than the value for the Caribbean

region, which is 0.15 per m2 (AGRRA, 2005). The removal of D. antillarum led to a lack of

any major kind of grazers and a rapid increase in the abundance of fleshy algae, which in

turn led to a reduction in fish abundance and hard coral cover (Sheppard et al., 2009). It

is probable, however, that abundant herbivorous fish populations have probably kept algal

growth within ecologically tolerable limits (Wilkinson, 2008).

Banded coral shrimps are a widespread and abundant decapod sought after in the

aquarium trade for their bright colour and ease of maintenance. Their abundance, 0.00313

individuals per m2, also appears to be low in our region, however both of these species are

frequently concealed under overhangs and in crevices during the day and thus may not

have been noticed by recorders.

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3. Community Work Programme

3.1 IntroductionGVI is committed to working with the local communities, assisting them to guide

Mahahual´s development towards a sustainable future. For that, we center our activities in

two main aspects: English and Environmental Education.

GVI hopes to provide locals in Mahahual with the tools to develop the area beneficially for

themselves, their professions and needs, whilst protecting it for the future. Consequently,

during both the child and adult education programs, wherever possible an environmental

theme has been included within the structure of the lesson.

3.2 Objectives

The objectives of the community programme at Punta Gruesa are:

1. To raise awareness about the importance of the surrounding ecosystems,

providing information and organizing activities to reinforce the knowledge given.

2. To provide English lessons that will help to develop necessary skills in order to be

able to communicate with the growing tourist visitors that come to the area.

3. To participate in the different activities that are organized by the local community

and provide help if it is needed.

3.3 Activities and Achievements

The program was carried out in three main areas: English lessons at the primary school

on Tuesday and Thursday mornings; Environmental education at the secondary school

on Tuesday and Thursday mornings, and English lessons for adults and children at the

primary school on a Thursday evening.

The English lessons for children are carried out while they are at school. The volunteers

prepare the lesson that will be given the day before. Games, interactive activities and

songs are part of the tools they use to reinforce the knowledge. After the lesson they have

feedback sessions between themselves to comment on how the lesson went.

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Lessons in the evening are the most successful due to the working times of the majority of

the students, which are mainly taxi drivers, builders, waiters, masseuses and sales people.

Numbers can vary, but on average up to 10 or more adults regularly attend. The structure

of these lessons is usually led by the participants who have specific requirements based

on their careers.

3.4 Review

English Language Programme

The school year ends in late July and begins again in early September. During the school

year the volunteers taught English in the primary school from 9:30 to 10:30 am. In the

evening, English lessons for adults were broken into two sessions from 16:30 to 18:00,

and then from 18:30 to 20:00; some children also attended these sessions.

Since GVI has moved to Punta Gruesa the number of cruise ships docking in Mahahual

has greatly increased. A major source of finance to the economy is from these cruise

ships and the majority of passengers from the cruise ships speak English, thus this is

a great incentive for those running businesses in Mahahual to learn English in order to

increase their sales. During the cruise ship ‘season’ there are a lot more people working in

Mahahual as they travel from Chetumal, Limones, Pedro Santos and several other towns

nearby, thus there is greater attendance during this time of year.

In the past, English lessons held when the schools are closed proved to be more

complicated to facilitate as it was more difficult to reach children directly. Posters were put

up around Mahahual to inform the general public, however organising a central locality to

hold the lessons, at a time of day that would suit the majority, proved more difficult than

when the primary school was open and available to use for lessons.

Generally, however, the volunteers and students alike seemed to enjoy this experience,

and felt a sense of accomplishment in doing it.

Environmental Education

This program took place in the secondary school every Tuesday and Thursday from 11:30

to 12:30pm.

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The lessons were given in Spanish, thus it was important that there was always a Spanish

speaker in the group to assist with translation; however, some of the students could speak

English. The volunteers were generally very keen in participating and helping out with the

activities and/or games organized.

Other Programmes and Activities

This phase we had the opportunity to reinforce our relationship with the Tulum community

for the Tortuga Festival. Every year GVI help one of their project partners, Casa de la

Cultura de Tulum, to organise this festival to celebrate the end of the turtle nesting season.

The volunteers helped to organise games and activities to raise general environmental

awareness of the presence of turtles in the region, as well as highlighting their vulnerability

to anthropogenic influences, and how we can help to minimise these impacts.

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4. Incidental Sightings Programme

4.1 Introduction

GVI Punta Gruesa implemented an incidental sightings program in January 2008, following

on from the previous work carried out in the twon of Mahahual. The species that make up

the incidental sightings list are:

● Sharks and Rays

● Eels

● Turtles

● Marine Mammals

● Great Barracuda

● Lionfish

These groups are identified to species level where possible and added to the data

collected by the Ocean Biogeographic Information Systems Spatial Ecological Analysis of

Megavertebrate Populations (OBIS-SEAMAP) database. An interactive online archive for

marine mammal, seabird and turtle data, OBIS-SEAMAP aims to improve understanding

of the distribution and ecology of marine megafauna by quantifying global patterns of

biodiversity, undertaking comparative studies, and monitoring the status of and impacts on

threatened species.

4.2 AimsThe aim of the project is to record all megafauna sightings in the vicinity of Punta Gruesa

and to keep track of the population numbers and spread of lionfish.

4.3 Methodology

Each time an incidental sighting species is seen on a dive or snorkel it is identified, and

the date, time, location, depth it was seen at, and size are all recorded. The volunteers

are provided with a megafauna presentation during science training, to aid identification.

All the completed dives are logged by GVI, showing the total effort for each phase in

comparison with the species recorded. The number of snorkeling excursions into the

lagoon was not recorded but is believed to be relatively consistent with that of previous

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phases.

Previous Mahahual expeditions have recorded turtle nesting sites during the nesting

season. However in Punta Gruesa there are no nesting beaches so this programme has

been discontinued.

For the first time in Phase 093 GVI Punta Gruesa began recording lionfish sightings.

Over the past decade the Pacific Lionfish (Pterois volitans) has established itself along

the Atlantic coast as a result of multiple releases (intentional or otherwise) from private

aquaria. This invasive species, lacking in natural predators, has adapted well to the warm

waters of the Caribbean and is currently spreading its geographical range along the

Mesoamerican coastline.

4.4 Results

A total of 108 incidental sightings (excluding Great Barracuda and Lionfish) were recorded

during 242 site visits in Phase 104.

Elasbobranchs

Rays were the most commonly observed elasmobranchs. A total of 60 rays were seen, 37

of them Southern Stingrays (Figure 4-4-1).

Figure 4-4-1 Sightings of common elasmobranch species per site visit 091-104

Eels

A total of twelve moray eels were recorded in 104 which is equal to the sightings from

Phase 103. There were six sightings of green morays, five spotted morays and one

golden-tailed moray (Figure 4-4-2). The number of sightings has varied over previous

phases but for all three species, the three highest records are from Phases 092, 093 and

094. There have been far fewer sightings during 2010.

Figure 4-4-2 Sightings of moray eels per site visit 091-104

Turtles

This phase there were nine turtle sightings, which is equal to 0.04 turtle sightings per site

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visit (Figure 4-4-3), the lowest value on record.

Figure 4-4-3 Turtle sightings per site visit 091-104

Marine Mammals

During Phase 104 there were five dolphin encounters involving a total of 18 dolphins; six

atlantic spotted, nine bottlenose and three unidentified individuals. Phase 101 saw a huge

peak in dolphin numbers (Figure 4-4-4), with 24 encounters involving 128 dolphins. Since

then, the number of dolphin sightings has decreased and remained relatively stable

Figure 4-4-4 Number of dolphin encounters per site visit from 091-104

Great Barracuda

Sixteen Sphyraena barracuda (Great Barracuda) were recorded during Phase 104. S.

barracuda numbers peaked during Phase 092 but have steadily declined since then

(Figure 4-4-5).

Figure 4-4-5 Number of S. barracuda sightings per site visit from 091-104

Lionfish

During Phase 104 a total of 250 lionfish sightings were recorded. This is a huge increase

on the numbers recorded in previous phases. This survey has only been running for four

phases but the highest number recorded previous to Phase 104 was in 102 when 77 were

recorded.

Figure 4-4-6 Number of Lionfish Sightings per site visit 101-104

Figure 4-47 shows the size distribution of the recorded lionfish. 101 records from Phase

104 have not been included because exact sizes were not given.

Figure 4-4-7 Size distribution of lionfish recorded during Phases 101-104

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4.5 Discussion

Incidental sightings of large marine creatures are often good indicators of a healthy

ecosystem. These species are highly mobile animals and therefore their movements

depend on a range of external factors.

Elasmobranchs

Southern stingrays are the most common elasmobranches recorded. Sightings increased

steadily during 2009, peaking during Phase 093, but since then numbers have dropped

and remained relatively stable. Southern stingrays tend to spend a lot of time partially

buried in the sand, just off the wall. They are often very conspicuous at the dive sites,

which may partially explain the high numbers recorded. Other elasmobranch species

are sighted fairly regularly but not in sufficient numbers to make any conclusions about

changes in their abundance. This may be for a variety of reasons. Nurse sharks tend to

be nocturnal and often lie under ledges or overhangs making them difficult to spot. Lesser

electric rays and yellow stingrays, as well as being well hidden, tend to inhabit shallow

sandy areas like seagrass beds or lagoons. They are less likely to be spotted on the reef

itself, where the majority of our activities are carried out.

Eels

All three eel species were recorded in relatively large numbers during the last three

phases of 2009. Since then the number of sightings has decreased. It is unlikely that the

number of eel sightings accurately reflects the abundance of each species as they are

rarely to be found out in the open. During the day, most species are reclusive and tend to

hide in dark recesses (Humann & DeLoach, 2008) making them very difficult to spot. The

reason behind the apparent drop in numbers since 2009 is unknown.

Turtles

The total number of turtles recorded at Punta Gruesa during Phase 104 was the lowest

recorded over the past two years. The number of hawksbill turtles has decreased steadily

over this period with Phase 104 having the lowest number of sightings recorded over that

time. This contradicts the work of Beggs et al., (2007) who found that that there has been

up to an eight fold increase in the number of Hawksbill nests in Barbados suggesting an

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increase in numbers. This apparent rise in the Caribbean population is also backed up

by the attempts from Cuba to downgrade Eretmochelys imbriocota to Appendix II on the

CITES list (www.cites.org). This unfortunately was mainly to enable the reopening of the

legal Hawksbill shell trade route with Japan which has been closed since 1993. Appendix

II would allow this under regulations (CITES Regulation of Trade Article IV).

Loggerhead turtle numbers have peaked during the second phase of the past two years.

Although turtles do not nest on the beaches of Punta Gruesa during the May-September

nesting season, many beaches in the area are used. This is why more turtles are sighted

at the start of the nesting season (the second phase of the year), and few after the end of

the season (the fourth phase).

Marine mammals

Dolphin numbers have remained relatively stable, with the exception of Phase 101, which

saw an increase in observations. Their behaviour is very unpredictable but sightings tend

to increase during cooler periods.

Great Barracuda

An important apex predator alongside sharks, S.barracuda populations help to maintain

a healthy equilibrium within coral reef ecosystems. The reefs in the area are subjected

to low level fishing pressure from a group of six to ten spear fishermen. The fishermen

fish the reef on average once a week targeting Great Barracuda alongside other fish

species. In addition to spearfishing, the coastline also plays host to sporadic game fishing

tournaments during which S. barracuda are one of the species caught.

The number of sightings throughout 2010 have been consistently low, whereas in 2009

they were recorded in much higher numbers. The reasons for such a significant decrease

in S. barracuda sightings is unclear but may be partially attributed to a lack of observations

of schooling behaviour. No more than two individuals were seen together this phase

compared to Phase 102 when 11 individuals were observed in a group or phase 093 when

15 S. barracuda were seen together. It is not yet understood whether schooling of large

members of the species is subject to seasonal variation but hopefully this will become

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clear with long term data collection.

Lionfish

After their arrival in the Caribbean in 1992 (Schofield, 2009) the population of lionfish has

increasing exponentially, to the point where there are now densities being reported off

the Bahamas of 300 individuals per hectare. The first reported sightings in the Sian Ka’an

Bioreserve were in May 2009 in the small fishing village of Punta Allen. Since then, there

have been numerous specimens reported in the reserve covering a range of habitats.

There are 3 major problems caused by P. volitans. Firstly, due to their recent arrival into

the ecosystem there are no natural predators to keep their numbers in check. Although

limited reports have been made of predation by Mycteroperca tigris, Tiger Grouper, and

anecdotal evidence provided by fishermen suggest that Epinephelus striatus, Nassau

Groupers, have been feeding with some regularity (Maljkovic et al., 2008) there have

been no documented cases of predation on a large scale. Secondly, their reproductive

strategy has meant that their population is flourishing, much to the suspected detriment

of other species. They lay between 15 and 30,000 eggs over a four day period every

month throughout the year. Finally, P. volitans is a voracious piscivore. There have been

documented cases of over 21 individual specimens found in the stomach of a 25cm

organism. This, combined with their hunting method, Lionfish use their outstretched

pectoral fins to slowly pursue and corner their prey (Allen & Eschmeyer, 1973), and the

lack of experience of prey species with this behaviour, may increase their predation

efficiency (Whitfield et al., 2002).

However, without knowledge of diet, dietary preferences and foraging requirements,

the impact of lionfish on prey populations and potential competitors for food cannot be

evaluated (Whitfield et al., 2002).

Phase 104 has seen a huge increase in numbers, with 250 being recorded in total.

Previous reports have observed that the majority of observations have seen the lionfish

under overhangs or in swim-throughs but recent anecdotal evidence suggests that they

are frequently spotted out in the open on the reef top.

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Of the 149 for which sizes were recorded, 18 of them fell in the 26cm+ category, which

unfortunately does suggest that there are reproductively mature individuals in the

population and that we should expect to a see an increase in the number of sightings over

the coming phases. Due to the nature of the diving here at Punta Gruesa it is not always

feasible to catch every lionfish on sighting it so multiple observations will inevitably occur.

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5. Marine Litter Monitoring Programme

5.1 Introduction

Phase 092 saw the beginning of the marine litter monitoring program at Punta Gruesa.

Marine litter is prevalent along the Caribbean coast and is not only unsightly but a health

hazard to marine life and humans alike. In order to collect more data on this issue a beach

clean program will be conducted every phase. This is part of a worldwide program and is

just one method of investigation to discover where marine litter originates from and which

materials are most common.

Figure 5-1-1 Marine litter washed up on the beach at Punta Gruesa

5.2 Aims

This project has three main aims:

● Quantified data and photographic evidence as to the extent of marine litter.

● Conservation of terrestrial and marine fauna threatened by litter.

● Improvement of beach aesthetics.

5.3 Methodology

Marine litter is collected weekly on a 200 metre stretch of beach north of base. The

transect is cleared one week prior to the commencement of the monitoring program, in

order that only a weekly amount of debris is recorded. Materials are collected from the

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tidemark to the vegetation line to eliminate waste created by inland terrestrial sources.

The waste is separated, weighed and recorded by the categories below:

● Fabric

● Glass

● Plastic

● Polystyrene

● Metal

● Natural material (modified)

● Medical waste

● Rubber

● Rope

● Other

5.4 Results

54.92kg of marine litter was collected during Phase 104 (Table 5-3-1). It should also be

noted that, although polystyrene contributes only an insignificant amount to the total weight

of litter collected (only 2.5%), small pieces of polystyrene are one of the most abundant

items to be found on the transect (personal observation).

Fabric (0 kg) Natural material (modified) (4.05 kg)

Glass (7.07 kg) Medical waste (0.2 kg)

Plastic (21.74 kg) Rubber (0 kg)

Polystyrene (1.4 kg) Rope (0.14 kg)

Metal (8.5 kg) Other (11.82 kg)

Table 5-3-1 Marine litter collected as actual weight (kg) for Phase 104

Figure 5-3-1 Percentage of total weight by category for Phase 104

The amount of litter seems to peak during the fourth phase each year (Figure 5-3-2).

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Plastic has been the heaviest category, on average, every phase since the survey began.

Several of the categories also seem to have exhibited a steady increase over this time,

including Metal, Natural Materials and Other.

Figure 5-3-2 Average weekly weight of rubbish collected by phase

5.5 Discussion

Punta Gruesa’s location on the Yucatan Peninsula means that it faces the Caribbean

Current. This is a circular current that combined with the Loop current and the Yucatan

current, transports a significant amount of water northwest-ward through the Caribbean

Sea. The main source is from the equatorial Atlantic Ocean via the North Equatorial, North

Brazil and Guiana Currents. Due to the volume of water that is transported and both the

nature and origin of these currents, it is possible that the litter being found is from quite

far afield. This could be compounded by the high shipping pressures, in particular the

cruise ships that pass through to Mahahual on a regular basis on average carrying approx

2-3,000 passengers. Other factors also include outflows from rivers and storm drains

etc. If this is the most common source for the marine debris then it is likely that weather

changes, which have an impact on both tidelines and sea turbulence, will have a direct

and noticeable effect on the amount of rubbish washed up.

As has been the case for every phase, plastics have again constituted the largest volume

of all the categories, being responsible for 39.6% of the total weight collected. This

could be due to its light weight making it easy to transport and its robustness against

degradation. The fact that the level of plastic found is consistently high from phase to

phase is a worrying trend, as when plastics such as Polythene, found in plastic bags,

breakdown they form small plastic particles that can contaminate the food web and

be passed on through the trophic levels. Plastic debris can act like a sponge for toxic

chemicals soaking up compounds such as PCB’s and DDE (a product from the breakdown

of DDT). Once these are ingested into the food chain, the high concentrations will be

spread from organism to organism until the levels become fatal.

When looking at the results, Polystyrene looks as though it only contributes to a very

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small percentage of the litter collected. This is due to its light weight though, rather than

its absence. In reality it accounts for a large volume of the litter collected. As with the

plastic this could be due to its resilience and light weight making it easy to transport long

distances.

Even though the data shows a large volume of rubbish being collected from a relatively

small section of beach, it is possible that the results do not do justice to the actual problem

at hand. This is due to the seagrass bed situated alongside the monitoring area. As

discussed above it is possible that during times of increased wind and wave action, the

volume of rubbish collected should show a marked increase. However this could be being

masked by the large quantity of Thalassia testudinum that also gets washed up in these

more extreme conditions, burying the rubbish and hiding it from sight. In some areas the

mound of dead blades can be as much as 75 cm deep.

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6. Bird Monitoring Programme

6.1 Introduction

A bird monitoring programme was initiated in April 2009.

With regard to avi-fauna, Mexico, Central and South America can be divided into three

distinct regions separated by mountain ranges: the Pacific slope, the Interior and the

Atlantic slope. These regions can be further divided into other sub-zones, based on a

variety of habitats.

The Yucatan Peninsula lies on the Atlantic slope and is geographically very different

from the rest of Mexico: It is a low-level limestone shelf on the east coast extending

north into the Caribbean. The vegetation ranges from rainforest in the south to arid scrub

environments in the north. The coastlines are predominantly sandy beaches but also

include extensive networks of mangroves and lagoons, providing a wide variety of habitats

capable of supporting large resident populations of birds.

Due to the location of the Yucatan peninsula, the population of resident breeders is

significantly enlarged by seasonal migrants. There are four different types of migratory

birds: Winter visitors migrating south from North America during the winter (August to

May); Summer residents living and breeding in Mexico but migrating to South America

for the winter months; Transient migrants breeding in North America and migrating to

South America in the winter but passing through Mexico; Pelagic visitors living offshore but

passing through the region.

Punta Gruesa is located near the town of Mahahual close to the Mexico/Belize border

between a network of mangrove lagoons and the Caribbean Sea. The local area contains

three key ecosystems; wetland, forest and marine environments.

6.2 Aims

● Develop a species list for the area

● Investigate the abundance and diversity of bird species. Long-term bird data

gathered over a sustained period could highlight trends not noticeable in short-term

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surveys.

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● Educate the volunteers in bird identification techniques, expanding on their general

identification skills. The birding project also provides a good opportunity to obtain a

better understanding of area diversity and the ecosystem as a whole.

6.3 Methodology

Bird monitoring surveys are conducted using a simple methodology based on the bird

monitoring program at Pez Maya. A member of staff and one or two volunteers monitor

one of four transects daily between 6 and 8am. There are four transects - Beach south,

Beach north, Road south and Road north. These transects were selected to cover a range

of habitats, including coastline, mangroves, secondary growth and scrub. The transects

are completed in approximately 30 minutes to allow for consistency of data. To reduce

duplication of data, recordings are taken in one direction only to avoid double-counting

where individuals are very active or numerous. Birds are identified using binoculars,

cameras and a range of bird identification books. Identification of calls is also possible for

a limited number of species for experienced observers. If the individual species cannot be

identified then birds are recorded to family level.

Each survey records the following information - location, date, start time, end time, name

of recorders and number of each species seen. Wind and cloud cover have also been

recorded to allow consideration of physical parameters.

6.4 Results

A total of 1774 birds were recorded this phase; the most recorded in a single phase since

the survey began. A total of 35 species were identified including seven new species, which

have been added to the species list (see Appendix VI). Great-tailed grackles (Quiscalus

mexicanus) were the most commonly sighted birds followed by sanderlings (Calidris alba)

and magnificent frigates (Fregata magnificens) (Figure 6-4-1).

Figure 6-4-1 Composition of common bird species (30 or more sightings) in Phase 104 Figure 6-4-2 Composition of most common (average 5% or more) bird sightings as a percentage across

all phases (092-104)

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Species new in Phase 104 include the Ferruginous pygmy owl, Groove-billed Ani,

Mangrove warbler, Swainson´s warbler, Tropical kingbird, White-eyed vireo and White-

tipped dove.

6.5 Discussion

Great-tailed grackles, golden-fronted woodpeckers and tropical mockingbirds are all

resident breeders in the area and magnificent frigates and brown pelicans are described

as common residents (Howell & Webb, 2004).

Royal terns, however, are described as being winter (non-breeding) visitors, as are

sanderlings, which were the second most common species during Phase 104. Royal terns

have been recorded here every phase since the survey began, but certainly their numbers

were highest during phases which cover the winter period. The two highest records are

for Phase 101 (95 individuals) and Phase 104 (64 individuals). The two highest numbers

recorded have been during Phase 101 (56 individuals) and Phase 104 (253 individuals),

both of which are winter phases.

The methodology followed in the birding project is somewhat limited as to the reliability

of collecting hard data; it will be of most use in simply determining species presence or

absence. Limited visibility and the inexperience of the recorders can often make a positive

identification difficult and tends to bias observations towards those species that are easily

observed or heard, whether due to size or behavioural attributes, or those commonly seen

and recognised. It is also very easy to misidentify similar species, such as among the

Orioles and Warblers.

The beach and road transects are very close together and in some places the areas under

observation overlap, thus they have not been separated for purposes of comparison: the

habitat is probably not sufficiently different on this scale.

The birding project at Punta Gruesa is in its infancy. The species list is constantly being

expanded as observers become more adept at seeing and identifying species and as

migrant species enter the area. As yet the data is insufficient to draw any conclusions

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as to any patterns or trends, however some fluctuations in the populations of common

species can already be seen between the phases of data collection.

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7. Seagrass Monitoring Programme

7.1 Introduction

Phase 102 (April-June 2010) saw the implementation of a new survey program, focusing

on the sea grass beds found adjacent to the beach at Punta Gruesa. The shoreline here

is dominated by a shallow, almost continuous bed that stretches from the waters edge to

the back reef approximately half a kilometre away. It is characterised by two main species,

Thalassia testudinum and Syringodium filiforme.

The seagrass beds are an intrinsic part of the marine ecosystem providing not only shelter

to juvenile reef fish but also helping to slow the water currents/movement in the lagoon,

decreasing the levels of coastal erosion and providing favourable conditions for both the

mangroves and reefs to grow.

7.2 Aims The aims of the project are:

● Determine the overall percentage coverage and species composition along three

transect lines and to find out if these values change with proximity to the reef.

● Monitor the changes in seagrass coverage and species composition over time.

● Monitor the health of the seagrass bed by measuring blade length, predation and

epiphyte cover.

7.3 Methodology

In order to monitor the health of this ecosystem, three transects have been set up; T1,

T2 and T3 (T1 being closest to the beach and T3 being furthest away). Their positioning

was based on relative distance from the edge of the bed and at a point of change in the

biological composition of the bed.

T1A 19.00810087.58933

T1B 19.00790087.58941

T1C 19.00770087.58949

T2A 19.00785087.58875

T2B 19.00765087.58883

T2C 19.00744087.58889

T3A 19.00748087.58767

T3B 19.00724087.58772

T3C 19.00703087.58779

Table 7-3-1 GPS positions for seagrass transects (Units in WGS 84 Format hddd.dddddo )

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Starting at point T1A (the most northerly point) a 1mx1m quadrat was laid on the shore

side of the transect line and the following measurements were taken;

● Overall percentage cover.

● S. filiforme percentage cover.

● T. testudinum percentage cover

● On 20 random T. testudinum blades within each quadrat, blade length, signs of

predation (yes or no) and percentage cover of epiphytes was recorded.

This was repeated at 5m intervals across the length of each transect giving ten repeats per

transect.

This methodology allows a rapid assessment of an otherwise uncharted area of seagrass

in the Punta Gruesa area. Due to the fact that they play such a crucial ecological role

in the health of the reef sytems, as a result of the habitual symbiosis shared between

seagrass beds, reefs and mangroves, it is important to monitor and assess the seagrass

beds.

This methodology enables GVI Mexico to obtain baseline data on the species composition,

percentage cover and condition so that changes in the health and structure can

be monitored over an extended period of time. The methodology is based on the

methodology of seagrassnet.com with slight modifications to accommodate for volunteers

with limited training.

7.4 Results

The seagrass survey was carried out during Phase 102 and Phase 104.

The average percentage cover of seagrass is highest on the transect closest to the beach

(Figure 7-4-1) and the percentage cover decreases as distance from the beach increases.

This is due to a drop in T. testudinum cover (Figure 7-3-2). S. filiforme cover was highest

on transect 2.

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T. testudinum has been found to be the dominant species on all three transects. Transect

1 had the greatest difference in cover between the two species. During Phase 104 the T.

testudinum cover on transect 1 was 87.5% whereas the S. filiforme cover was only 3.8%.

Transect 2 has a more even cover of the two species with 45.5% T. testudinum and 30.0%

S. filiforme.

Figure 7-4-1 Average percentage cover of seagrass on seagrass transects during Phase 102 and 104

Figure 7-4-2 Average percentage cover of T. testudinum and S. filiforme on seagrass transects during Phase 102 and 104

Figure 7-4-3 Average blade length of T. testudinum on seagrass transects

T. testudinum on transect 3 was found to have the shortest average blade length and T.

testudinum on transect 2 to have the longest blade length. During Phase 102 there was

found to be a positive correlation between the average T. testudinum blade length in a

quadrat and the number of blades in that quadrat showing signs of predation (Figure 7-4-

4). With a Polynomial regression the R2 value is only 0.58 showing that although there is a

relationship, statistically it is very weak. This relationship is not apparent in the data from

Phase 104 (Figure 7-4-5).

Figure 7-4-4 Relationship between T. testudinum blade length and predation during Phase 102

Figure 7-4-5 Relationship between T. testudinum blade length and predation during Phase 104

Average epiphyte cover varies between transects (Figure 7-4-6). During Phase 104, the

highest epiphyte cover was found on transect 1 and the lowest on transect 3. During

Phase 102 the highest epiphyte cover was found on transect 1 and the lowest on transect

2.

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Figure 7-4-6 Average epiphyte cover on T. testudinum blades on seagrass transects during Phase 102 and 104

7.5 Discussion

T. testudinum was found to be the more dominant species on all three transects during

both 102 and 104. Williams (1987) observed a decline in S. filiforme shoot density

as T. testudinum became dominant during temporal development and found that this

was a result of exploitative competition primarily for sediment nutrients but also light.

T. testudinum has a much greater leaf area for inception of light than S. filiforme. For

example, a typical leaf width for T. testudinum is 1 cm in contrast to just over 1 mm for S.

filiforme.

T. testudinum on transect 3 (closest to the reef) was found to have the shortest average

blade length and the T. testudinum on transect 2 was found to have the longest blade

length. Sweatman and Robertson (1994) found that T. testudinum provided minimal cover

(for juvenile fish) near to the reef edge because the blades were grazed short. They found

that blade length increased with distance from the reef edge. This could partially explain

the pattern observed here.

Average percentage cover of seagrass is highest on transect 1, which is closest to the

beach, and lowest on transect 3, which is closest to the reef. This is due to a drop in T.

testudinum cover. Sweatman & Robertson (1994) found that T. testudinum blade density

was similar at all of their sample distances from the reef. It is possible that the density

across the three transects at Punta Gruesa may be similar. There may appear to be a

difference in percentage cover due to differences in average blade length discussed

above.

During Phase 102 there was found to be a positive correlation between the average

T. testudinum blade length in a quadrat and the number of blades showing signs of

predation. This may be due to longer blades being more of a target for herbivores or

longer blades may be older and therefore have had more time to suffer from grazing. This

relationship is not apparent in the data from Phase 104

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As previously mentioned this is only the second time this study has been conducted

at Punta Gruesa so it is hard to make any conclusions about the current state of the

seagrass bed. This has been useful to try and determine a baseline percentage cover

and see the beginning of relationships, however, before any definitive conclusions can be

made further work is required to determine the viability of these findings and to allow for

seasonal variations.

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Indicators of Coral Reef Health

AGRRA (2000) Atlantic and Gulf Rapid Reef Assessment (AGRRA). The AGRRA Rapid

Assessment Protocol. http://www.agrra.org/method/methodhome.htm

Allen, G. R. & Eschmeyer, W. N. (1973) Turkeyfishes at Eniwetok. Pacific Discovery 26:3-

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Almada-Villela P.C., Sale P.F., Gold-Bouchot G. and Kjerfve B. (2003) Manual of Methods

for the MBRS Synoptic Monitoring System: Selected Methods for Monitoring Physical and

Biological Parameters for Use in the Mesoamerican Region. Mesoamerican Barrier Reef

Systems Project (MBRS)

Beach, K., Walters, L, Borgeas, H, Smith, C., Coyer, J., Vroom P. (2003) The impact

of Dictyota spp. on Halimeda populations of Conch Reef, Florida Keys. Journal of

Experimental Marine Biology and Ecology 297: 141-159.

Beggs, J.A., Horrocks, J.A., Kreuger, B.H. (2007) Increase in Hawksbill Sea Turtle

Eretmochelys imbricate Nesting in Barbados

Conservation on International Trade of Endangered Species of Wild Flora and Fauna

(CITES) Regulation of Trade Article IV (www.cites.org)

Darwall, W. R. T. & Dulvy, N. K. (1996) An evaluation of the suitability of non-specielist

volunteer researchers for coral reef fish surveys. Mafia Island, Tanzania – A case study.

Biological Conservation. Volume 78. Issue 3: 223-231

Dawes, C. J., Mathieson, A. C., Cheney, D. P. (1974) Ecological Studies of Floridian

Eucheuma (Rhodophyta, Gigartinales). I. Seasonal Growth and Reproduction. Bulletin of

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Marine Science. Volune 24. Number 2.

DeLoach, N. (1999) Reef fish behaviour: Florida, Caribbean, Bahamas. New World

Publications. Artegrafica. Verona, Italy.

Edmunds, P.J. and Carpenter, R.C. (2001) Recovery of Diadema antillarum reduces

macroalgal cover and increases abundance of juvenile corals on a Caribbean reef. PNAS

98(9): 5067-5071.

Froese, R. and Pauly, D. (Editors) (2006) Fishbase. World Wide Web electronic

publication. www.fishbase.org version (06/2006)

Accessed 17/11/06

Franklin, J. L. (2008) Tropical Cyclone Report: Hurricane Dean. National Hurricane Centre

http://www.nhc.noaa.gov/pdf/TCR-AL042007_Dean.pdf

Gardener, T.A., Cote, I.M., Gill, J.A., Grant, A., Watkinson, A.R. (2005) Hurricanes

and Caribbean Coral Reefs: Impacts, recovery patterns, and role in long-term decline.

Ecology 86(1): 174-184.

Gardener, T.A., Cote, I.M., Gill, J.A., Grant, A., Watkinson, A.R. (2003) Long-term region-

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Howell, S. N. G., and Webb, S. (2004) A Guide to the Birds of Mexico and Northern

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Humann, P. & DeLoach, N. (2002) Reef Creature Identification: Florida, Caribbean,

Bahamas. New World Publications, Inc., Jacksonville, Florida

Humann, P. & DeLoach, N. (2008) Reef Coral Identification: Florida, Caribbean, Bahamas.

New World Publications, Inc., Jacksonville, Florida.

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Humann, P. & DeLoach, N. (2008) Reef Fish Identification: Florida, Caribbean, Bahamas.

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9. Appendices

Appendix I – SMP Methodology Outlines Buddy method 1: Surveys of corals, algae and other sessile organisms

At each monitoring site five replicate 30 m transect lines are deployed randomly within

100 m of the GPS point. The transect line is laid across the reef surface at a constant

depth, usually perpendicular to the reef slope. The relatively recent discovery of a Spur

and Groove site, LG, at a depth of 20 m will allow for additional future monitoring. In

keeping with Scuba diving profiles at such depths, two buddy pairs usually work together

on each 30m transect in order to complete monitoring surveys and return to the surface

safely. Owing to the nature of the Spur and Groove reef orientation, transects will be laid

perpendicular to the shoreline.

The first diver measures the percentage cover of sessile organisms and substrate along

the 30 m transect, recording the nature of the substrate or organism every 25 cm along the

transect. Organisms are classified into the following groups:

● Coralline algae - crusts or finely branched algae that are hard (calcareous) and

extend no more than 2 cm above the substratum

● Turf algae - may look fleshy and/or filamentous but do not rise more than 1 cm

above the substrate

● Macroalgae - include fleshy and calcareous algae whose fronds are projected more

than 1 cm above the substrate. Three of these are further classified into additional

groups which include Halimeda, Dictyota, and Lobophora

● Gorgonians

● Hermatypic corals - to species level, where possible

● Bare rock, sand and rubble

● Any other sessile organisms e.g. sponges, tunicates, zoanthids, hydroids and

crinoids.

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The second diver of this monitoring buddy pair collects data on the characterisation of

the coral community under the transect line. Swimming along the transect line the diver

identifies, to species level, each hermatypic coral directly underneath the transect that

is at least 10cm at its widest point and in the original growth position. If a colony has

been knocked or has fallen over, it is only recorded if it has become reattached to the

substratum.

The diver then identifies the colony boundaries based on verifiable connective or common

skeleton. Using a measuring pole, the colonies projected diameter (live plus dead areas)

in plan view and maximum height (live plus dead areas) from the base of the colonies

substratum are measured.

From plane view perspective, the percentage of coral that is not healthy (separated into

old dead and recent dead) is also estimated.

The second diver also notes any cause of mortality including diseases and/or predation

and any bleached tissue present. The diseases are characterised using the following nine

categories:

● Black band disease ● Red band disease

● White band disease ● Hyperplasm and Neoplasm (irregular growths)

● White plague ● Patchy necrosis or White Pox

● Yellow blotch disease ● Unknown

● Dark spot disease

Predation and overgrowth are also recorded on each of the coral colonies. The following

categories are considered:

● Parrotfish predation ● Fire coral predation

● Damselfish predation ● Gorgonian predation

● Fireworm predation ● Zoanthid predation

● Short coral snail predation ● Coralline algae overgrowth

● Overgrowing mat tunicate ● Sponge overgrowth

● Variable boring sponge ● Cliona sp.

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Bleaching is split into three categories, pale, partial and total.

● Pale – majority of the coral is faded in colour but not totally white

● Partial – a significant amount of the coral is totally or near-totally bleached

● Total – all or almost all of the coral is totally bleached, i.e. completely white

Any other features of note are also recorded, including, orange icing sponge, coral

competition and Christmas tree worms.

Buddy method 2: Belt transect counts for coral reef fish

At each monitoring site 8 replicate 30m transects lines are deployed randomly within

100m of the GPS point. The transect line is laid just above the reef surface at a constant

depth, usually perpendicular to the reef slope. The first diver is responsible for swimming

slowly along the transect line identifying, counting and estimating the sizes of specific

indicator fish species in their adult phase. The diver visually estimates a two metre by two

metre ‘corridor’ and carries a one meter T-bar divided into 10cm graduations to aid the

accuracy of the size estimation of the fish identified. The fish are assigned to the following

size categories:

● 0-5cm 21-30cm

● 6-10cm 31-40cm

● 11-20cm >40cm (with size specified)

The buddy pair then waits for three minutes at a short distance from the end of the

transect line before proceeding. This allows juvenile fish to return to their original positions

in case they were scared off by the divers during the adult transect. The buddy pair then

swims slowly back along the transect with the second diver surveying a one metre by one

metre ‘corridor’ and identifying and counting the presence of target juvenile species. In

addition, it is also this diver’s responsibility to identify and count the Banded Coral Shrimp,

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Stenopus hispidus. This is a collaborative effort with UNAM to track this species as their

population is slowly dwindling due to their direct removal for the aquarium trade. The

second diver also counts any Diadema antillarum individuals found on their transects.

This is aimed at tracking the slow come back of these urchins.

Buddy Method 3: Coral & Fish Rover divers

At each monitoring site the third buddy pair completes a thirty minute survey of the site in

an expanding square pattern or a U-shaped pattern, with one diver recording all adult fish

species observed. The approximate density of each fish species is categorised using the

following numerations:

● Single (1 fish)

● Few (2-10 fish)

● Many (11-100 fish)

● Abundant (>100 fish)

The second diver swims along side the Fish Rover diver and records, to species level, all

coral communities observed, regardless of size.The approximate density of each coral

species is then categorised using similar ranges to those for fish:

● Single (1 community)

● Few (2-10 communities)

● Many (11-50 communities)

● Abundant (>50 communities)

Analyzing the rover data gives us a broader view of additional organisms that may

constitute the reef site but that may not be represented from the randomly placed transect

lines. In the case of fish data, the rover data aids in collecting population size information

of target species that may keep away from a transect line due to the intimidating and

possibly invasive nature of unnatural objects and divers on the reef.

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Appendix II - Adult Fish Indicator Species ListScientific Name Common Name Scientific Name Common Name

Acanthurus coeruleus, Blue Tang Scarus guacamaia Rainbow Parrotfish

Acanthurus bahianus, Ocean Surgeonfish Scarus vetula Queen Parrotfish

Acanthurus chirurgus, Doctorfish Sparisoma viride Stoplight Parrotfish

Chaetodon striatus, Banded Butterflyfish Scarus taeniopterus Princess Parrotfish

Chaetodon capistratus, Four Eye Butterflyfish Scarus iserti Striped Parrotfish

Chaetodon ocellatus, Spotfin Butterflyfish Sparisoma aurofrenatum Redband Parrotfish

Chaetodon aculeatus, Longsnout Butterflyfish Sparisoma chrysopterum Redtail Parrotfish

Haemulon flavolineatum French Grunt Sparisoma rubripinne Yellowtail Parrotfish

Haemulon striatum Striped Grunt Sparisoma atomarium Greenblotch Parrotfish

Haemulon plumierii White Grunt Sparisoma radians Bucktooth Parrotfish

Haemulon sciurus Bluestriped Grunt Epinephelus itajara Goliath Grouper

Haemulon carbonarium Caesar Grunt Epinephelus striatus Nassau Grouper

Haemulon chrysargyreum Smallmouth Grunt Mycteroperca venenosa Yellowfin Grouper

Haemulon aurolineatum Tomtate Mycteroperca bonaci Black Grouper

Haemulon melanurum Cottonwick Mycteroperca tigris Tiger Grouper

Haemulon macrostomum Spanish Grunt Mycteroperca interstitialis Yellowmouth Grouper

Haemulon parra Sailor’s Choice Epinephelus guttatus Red Hind

Haemulon album White Margate Epinephelus adscensionis Rock Hind

Anisotremus virginicus Porkfish Cephalopholis cruentatus Graysby

Anisotremus surinamensis Black Margate Cephalopholis fulvus Coney

Lutjanus analis Mutton Snapper Balistes vetula Queen Triggerfish

Lutjanus griseus Gray Snapper Balistes capriscus Gray Triggerfish

Lutjanus cyanopterus Cubera Snapper Canthidermis sufflamen Ocean Triggerfish

Lutjanus jocu Dog Snapper Xanithichthys ringens Sargassum Triggerfish

Lutjanus mahogoni Mahaogany Snapper Melichthys niger Black Durgon

Lutjanus apodus Schoolmaster Aluterus scriptus Scrawled Filefish

Lutjanus synagris Lane Snapper Cantherhines pullus Orangespotted Filefish

Ocyurus chrysurus Yellowtail Snapper Cantherhines macrocerus Whitespotted Filefish

Holacanthus ciliaris Queen Angelfish Bodianus rufus Spanish Hogfish

Pomacanthus paru French Angelfish Lachnolaimus maximus Hogfish

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Pomacanthus arcuatus Grey Angelfish Caranx rubber Bar Jack

Holacanthus tricolour Rock Beauty Microspathodon chrysurus Yellowtail Damselfish

Scarus coeruleus Blue Parrotfish Sphyraena barracuda Great Barracuda

Scarus coelestinus Midnight Parrotfish

The following list includes the adult fish species that are surveyed during monitoring dives.

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Appendix III - Juvenile Fish Indicator Species List The subsequent list specifies the juvenile fish species and their maximum target length

that are recorded during monitoring dives

Scientific Name Common Name Max. target length (cm)

Acanthurus bahianus Ocean surgeonfish 5

Acanthurus coeruleus Blue tang 5

Chaetodon capistratus Foureye butterflyfish 2

Chaetodon striatus Banded butterflyfish 2

Gramma loreto Fairy basslet 3

Bodianus rufus Spanish hogfish 3.5

Halichoeres bivittatus Slipperydick 3

Halichoeres garnoti Yellowhead wrasse 3

Halichoeres maculipinna Clown wrasse 3

Thalassoma bifasciatum Bluehead wrasse 3

Halichoeres pictus Rainbow wrasse 3

Chromis cyanea Blue chromis 3.5

Stegastes adustus Dusky damselfish 2.5

Stegastes diencaeus Longfin damselfish 2.5

Stegastes leucostictus Beaugregory 2.5

Stegastes partitus Bicolour damselfish 2.5

Stegastes planifrons Threespot damselfish 2.5

Stegastes variabilis Cocoa damselfish 2.5

Scarus iserti Striped parrotfish 3.5

Scarus taeniopterus Princess parrotfish 3.5

Sparisoma atomarium Greenblotch parrotfish 3.5

Sparisoma aurofrenatum Redband parrotfish 3.5

Sparisoma viride Stoplight parrotfish 3.5

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Appendix IV - Coral Species List

Family Genus Species Family Genus Species

Acroporidae Acropora cervicornis Meandrinidae Dendrogyra cylindrus

Acroporidae Acropora palmata Meandrinidae Dichocoenia stokesii

Acroporidae Acropora prolifera Meandrinidae Meandrina meandrites

Agariciidae Agaricia agaricites Milliporidae Millepora alcicornis

Agariciidae Agaricia fragilis Milliporidae Millepora complanata

Agariciidae Agaricia grahamae Mussidae Isophyllastrea rigida

Agariciidae Agaricia lamarcki Mussidae Isophyllia sinuosa

Agariciidae Agaricia tenuifolia Mussidae Mussa angulosa

Agariciidae Agaricia undata Mussidae Mycetophyllia aliciae

Agariciidae Helioceris cucullata Mussidae Mycetophyllia ferox

Antipatharia Cirrhipathes leutkeni Mussidae Mycetophyllia lamarckiana

Astrocoeniidae Stephanocoenia intersepts Mussidae Mycetophyllia reesi

Caryophylliidae Eusmilia fastigiana Mussidae Scolymia sp.

Faviidae Colpophyllia natans Pocilloporidae Madracis decactis

Faviidae Diploria clivosa Pocilloporidae Madracis formosa

Faviidae Diploria labrynthiformis Pocilloporidae Madracis mirabilis

Faviidae Diploria strigosa Pocilloporidae Madracis pharensis

Faviidae Favia fragum Poritidae Porites astreoides

Faviidae Manicina areolata Poritidae Porites divaricata

Faviidae Montastraea annularis Poritidae Porites furcata

Faviidae Montastraea cavernosa Poritidae Porites porites

Faviidae Montastraea faveolata Siderastridae Siderastrea radians

Faviidae Montastraea franksi Siderastridae Siderastrea sidereal

Faviidae Solenastrea bournoni Stylasteridae Stylaster roseus

Faviidae Solenastrea hyades

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Appendix V - Fish Species ListThis list was begun for Mahahual in April 2004. This list is compiled from the Adult and

Rover diver surveys.

Family Genus Species Common Names

Acanthuridae Acanthurus Bahianus Ocean surgeonfish

Acanthuridae Acanthurus Chirurgus Doctorfish

Acanthuridae Acanthurus Coeruleus Blue tang

Atherinidae, Clupeidae,

Engraulididae Silversides, Herrings,

Anchovies

Aulostomidae Aulostomus Maculates Trumpetfish

Balistidae Balistes Capriscus Gray triggerfish

Balistidae Balistes Vetula Queen triggerfish

Balistidae Canthidermis Sufflamen Ocean triggerfish

Balistidae Melichthys Niger Black durgon

Balistidae Xanithichthys Ringens Sargassum triggerfish

Bothidae Bothus Lunatus Peacock flounder

Carangidae Caranx Bartholomaei Yellow jack

Carangidae Caranx Crysos Blue runner

Carangidae Caranx Ruber Bar jack

Carangidae Trachinotus Falcatus Permit

Centropomidae Centropomus Undecimalis Common snook

Chaenopsidae Lucayablennius Zingaro Arrow blenny

Chaetodontidae Chaetodon Aculeatus Longsnout butterflyfish

Chaetodontidae Chaetodon Capistratus Foureye butterflyfish

Chaetodontidae Chaetodon Ocellatus Spotfin butterflyfish

Chaetodontidae Chaetodon Sedentarius Reef butterflyfish

Chaetodontidae Chaetodon Striatus Banded butterflyfish

Cirrhitidae Amblycirrhitus Pinos Red spotted hawkfish

Congridae Heteroconger Longissimus Brown garden eel

Dasyatidae Dasyatis Americana Southern stingray

Diodontidae Diodon Holocanthus Balloonfish

Elopidae Megalops Atlanticus Tarpon

Gobiidae Coryphopterus Eidolon Palid Goby

Gobiidae Coryphopterus Glaucofraenum Bridled goby

Gobiidae Coryphopterus Lipernes Peppermint goby

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Gobiidae Coryphopterus personatus/hyalinus Masked/glass goby

Gobiidae Gnatholepis Thompsoni Goldspot goby

Gobiidae Gobiosoma Oceanops Neon goby

Family Genus Species Common Names

Gobiidae Gobiosoma Prochilos Broadstripe goby

Grammatidae Gramma Loreto Fairy basslet

Grammatidae Gymnothorax Funebris Green moray

Grammatidae Gymnothorax Moringa Spotted moray

Haemulidae Anisotremus Virginicus Porkfish

Haemulidae Haemulon Album White margate

Haemulidae Haemulon Aurolineatum Tomtate

Haemulidae Haemulon Carbonarium Ceaser Grunt

Haemulidae Haemulon Flavolineatum French grunt

Haemulidae Haemulon Macrostomum Spanish grunt

Haemulidae Haemulon Plumierii White grunt

Haemulidae Haemulon Sciurus Bluestriped grunt

Haemulidae Haemulon Striatum Striped grunt

Haemulidae Anisotremus Surinamensis Black margate

Haemulidae Haemulon Parra Sailor’s choice

Holocentridae Holocentrus Adscensionis Squirrelfish

Holocentridae Holocentrus Rufus Longspine squirrelfish

Holocentridae Myripristis Jacobus Blackbar soldierfish

Holocentridae Neoniphon Marianus Longjaw squirrelfish

Holocentridae Sargocentron Bullisi Deepwater squirrelfish

Holocentridae Sargocentron Coruscum Reef squirrelfish

Holocentridae Sargocentron Vexillarium Dusky squirrelfish

Kyphosidae Kyphosus sectatrix/incisor Chub

Labridae Bodianus Rufus Spanish hogfish

Labridae Clepticus Parrae Creole wrasse

Labridae Halichoeres Bivittatus Slipperydick

Labridae Halichoeres Garnoti Yellowhead wrasse

Labridae Halichoeres Pictus Rainbow wrasse

Labridae Halichoeres Poeyi Blackear wrasse

Labridae Halichoeres Radiatus Puddingwife wrasse

Labridae Lachnolaimus Maximus Hogfish

Labridae Thalassoma Bifasciatum Bluehead wrasse

Labridae Xyrichtys Martinicensis Rosy razorfish

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Labridae Xyrichtys Novacula Pearly razorfish

Labrisomidae Malacoctenus Triangulatus Saddled blenny

Lutjanidae Lutjanus Analis Mutton snapper

Lutjanidae Lutjanus Apodus Schoolmaster snapper

Lutjanidae Lutjanus Cyanopterus Cubera snapper

Lutjanidae Lutjanus Griseus Grey snapper

Family Genus Species Common Names

Lutjanidae Lutjanus Jocu Dog snapper

Lutjanidae Lutjanus Mahogoni Maghogony snapper

Lutjanidae Lutjanus Synagris Lane snapper

Lutjanidae Ocyurus Chrysurus Yellowtailed snapper

Malacanthidae Malacanthus Plumieri Sand tilefish

Syngnathidae Micrognathus ensenadae Harlequin pipefish

Monacanthidae Aluterus Scriptus Scrawled filefish

Monacanthidae Cantherhines Macrocerus White spotted filefish

Monacanthidae Cantherhines Pullus Orange spotted filefish

Mullidae Mulloidichthys Martinicus Yellow goatfish

Mullidae Pseudupeneus Maculates Spotted goatfish

Myliobatidae Aetobatus Narinari Spotted eagle ray

Opistognathidae Opistognathus Aurifrons Yellowhead jawfish

Ostraciidae Acanthostracion Quadricornis Scrawled cowfish

Ostraciidae Lactophrys Bicaudalis Spotted trunkfish

Ostraciidae Lactophrys Triqueter Smooth trunkfish

Pempheridae Pempheris Schomburgki Glassy sweeper

Pomacanthidae Holacanthus Ciliaris Queen angelfish

Pomacanthidae Holacanthus Tricolour Rockbeauty

Pomacanthidae Pomacanthus Arcuatus Grey angelfish

Pomacanthidae Pomacanthus Paru French angelfish

Pomacentridae Abudefduf Saxatilis Seargant major

Pomacentridae Chromis Cyanea Blue chromis

Pomacentridae Chromis Enchrysurus Yellowtail reef fish

Pomacentridae Chromis Insolata Sunshinefish

Pomacentridae Chromis Multilineata Brown chromis

Pomacentridae Microspathodon Chrysurus Yellowtailed damsel fish

Pomacentridae Stegastes Adustus Dusky damselfish

Pomacentridae Stegastes Diencaeus Longfin damselfish

Pomacentridae Stegastes Leucostictus Beaugregory

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Pomacentridae Stegastes Partitus Bicolour damselfish

Pomacentridae Stegastes Planifrons Threespot damselfish

Pomacentridae Stegastes Variabilis Cocoa damselfish

Scaridae Scarus Coelestinus Midnight parrotfish

Scaridae Scarus Coeruleus Blue parrotfish

Scaridae Scarus Guacamaia Rainbow parrotfish

Scaridae Scarus Iserti Striped parrotfish

Scaridae Scarus Taeniopterus Princess parrotfish

Scaridae Scarus Vetula Queen parrotfish

Family Genus Species Common Names

Scaridae Sparisoma Atomarium Greenblotch parrotfish

Scaridae Sparisoma Aurofrenatum Redband parrotfish

Scaridae Sparisoma Chrysopterum Redtail parrotfish

Scaridae Sparisoma Radians Bucktooth parrotfish

Scaridae Sparisoma Rubripinne Yellowtail parrotfish

Scaridae Sparisoma Viride Stoplight parrotfish

Sciaenidae Equetus Lanceolatus Jackknife fish

Sciaenidae Equetus Punctatus Spotted drum

Sciaenidae Pareques Acuminatus Highhat

Scombridae Scomberomorus Maculates Spanish mackerel

Scombridae Scomberomorus Regalis Cero

Scorpaenidae Scorpaena Plumieri Spotted scorpionfish

Serranidae Cephalopholis Cruentatus Graysby

Serranidae Cephalopholis Fulvus Coney

Serranidae Epinephelus Adscensionis Rockhind

Serranidae Epinephelus Itajara Goliath grouper

Serranidae Epinephelus Striatus Nassau grouper

Serranidae Hypoplectrus Aberrans Yellowbelly hamlet

Serranidae Hypoplectrus Chlorurus Yellowtail hamlet

Serranidae Hypoplectrus Guttavarius Shy hamlet

Serranidae Hypoplectrus Indigo Indigo hamlet

Serranidae Hypoplectrus Nigricans Black hamlet

Serranidae Hypoplectrus Puella Barred hamlet

Serranidae Hypoplectrus Unicolor Butter hamlet

Serranidae Liopropoma Rubre Peppermint basslet

Serranidae Mycteroperca Bonaci Black grouper

Serranidae Mycteroperca Interstitialis Yellowmouth grouper

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Serranidae Mycteroperca Tigris Tiger grouper

Serranidae Mycteroperca Venenosa Yellowfin grouper

Serranidae Paranthias Furcifer Creolefish

Serranidae Rypticus Saponaceus Greater soapfish

Serranidae Serranus Tabacarius Tobaccofish

Serranidae Serranus Tigrinus Harlequin bass

Serranidae Serranus Tortugarum Chalk bass

Sparidae Calamus Calamos Saucereyed porgy

Sphyraenidae Sphyraena Barracuda Great barracuda

Synodontidae Synodus Intermedius Sand diver

Tetraodontidae Canthigaster Rostrata Sharpnosed puffer

Tetraodontidae Sphoeroides Splengleri Bandtail puffer

Torpedinidae Narcine Brasiliensis Lesser electric ray

Urolophidae Urolophus Jamaicensis Yellowstingray

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Appendix VI - Bird Species ListBird species identified to species level in Punta Gruesa since April 2009.

Common Name Family Scientific NameAltamira Oriole Icteridae Icterus gularisBlack Vulture Cathartidae Coragyps atratusBlack-backed Oriole Icteridae Icterus abeilli or bullockiiBlack-bellied Plover Charadriidae Pluvialis squatarolaBlack-cowled Oriole Icteridae Icterus dominicensisBlack-crowned Tityra Cotingidae Tityra inquisitorBrown Pelican Pelecanidae Pelecanus occidentalisCanivet's Emerald Hummingbird Trochilidae Chlorostilbon canivetiiCattle Egret Ardeidae Bubulcus ibisCommon Black Hawk Accipitridae Buteogallus anthracinusDusky Capped Flycatcher Tryrannidae Myiarchus tuberculiferEastern Kingbird Tyrannidae Tyrannus tyrannusFerruginous pygmy owl Strigidae Glaucidium brasilianumGolden-fronted Woodpecker Picidae Centurus aurifronsGreat Blue Heron Ardeidae Ardea herodiasGreat Egret Ardeidae Egretta alba egrettaGreat Kiskadee Tyrannidae Pitangus sulphuratusGreat-tailed Grackle Icteridae Quiscalus mexicanusGreen Heron Ardeidae Butorides virescensGreen Jay Corvidae Cyanocorax yncasGreen Kingfisher Alcedinidae Chloroceryle americanaGrey Kingbird Tyrannidae Tyrannus d. dominicensisGroove-billed Ani Cuculidae Crotophaga sulcirostrisHooded Oriole Icteridae Icterus cucullatusLaughing Falcon Falconidae Herpetotheres cachinnansLaughing Gull Laridae Larus atricillaLeast Tern Laridae Sterna antillarumLineated Woodpecker Picidae Dryocopus lineatusLittle Blue Heron Ardeidae Egretta caeruleaMagnificent Frigatebird Fregatidae Fregata magnificensMangrove Vireo Vireonidae Vireo pallensMangrove Warbler Parulinae Dendroica erithachoridesMasked Tityra Cotingidae Tityra semifasciataNeotropic Cormorant Phalacrocoracidae Phalacrocorax brasilianusOsprey Accipitridae Pandion haliaetusPalm Warbler Parulinae Dendroica palmarumPlain Chachalaca Cracidae Ortalis vetulaPurple Martin Progne Progne subisRoyal Tern Laridae Sterna m. maximaRuddy Ground-Dove Columbidae Columbina talpacotiRuddy Turnstone Scolopacidae Arenaria interpres

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Page 78: GVI Mexico Punta Gruesa Oct-Dec 2010 Annual report

Sanderling Scolopacidae Calidris albaSemipalmated Plover Charadriidae Charadrius semipalmatusSnowy Egret Ardeidae Egretta thulaSocial Flycatcher Tyrannidae Myiozetetes similisSwainson´s warbler Parulinae Helmitheros swainsoniiTropical Kingbird Tyrannidae Tyrannus melancholicusTropical Mockingbird Mimidae Mimus gilvusTurkey Vulture Cathartidae Cathartes auraWhite-eyed vireo Vireonidae Vireo griseusWhite Ibis Threskiornithidae Eudocimus albusWhite-tipped dove Columbidae Leptotila verreauxiWhite-winged Dove Columbidae Zenaida asiaticaWilson's Plover Charadriidae Charadrius wilsoniaYellow Warbler Parulinae Dendroica petechiaYellow-backed Oriole Icteridae Icterus chrysaterYellow-throated Vireo Vireonidae Vireo hypochryseusYellow-throated Warbler Parulinae Dendroica dominicaYucatan Jay Corvidae Cyanocorax yucatanicusYucatan Woodpecker Picidae Centurus pygmaeus

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