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1 An Analysis of Macaw Conservation Strategies at the Tambopata Research Center Brian Leahy Sophomore College 2013 October 14, 2013 Abstract: Macaws are becoming increasingly threatened with endangerment and, in some cases, extinction largely due to poor reproductive rate and progressively higher levels of deforestation and exploitation. As a way to combat the dwindling populations, macaw preservation techniques have been implemented in some South and Central American locations. The Tambopata Macaw Project in the Madre de Dios region of Peru has been the leading force of this macaw conservation effort. Their efforts at supporting the proliferation of this species have included the protection and management of macaw habitat, the construction of artificial macaw nests, and the hand-rearing of macaw chicks in captivity for later reintroduction into the wild. The increasing level of human contact with the ecology of macaw species in Tambopata, Peru has raised some concerns about how beneficial artificial breeding and rearing strategies are to the overall conservation of macaws. In this paper, the negative and positive effects of artificial strategies of macaw conservation taking Blue-and-yellow Macaws at the Collpa Colorado

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An Analysis of Macaw Conservation Strategies

at the Tambopata Research Center

Brian Leahy

Sophomore College 2013

October 14, 2013

Abstract:

Macaws are becoming increasingly threatened with endangerment and, in

some cases, extinction largely due to poor reproductive rate and progressively

higher levels of deforestation and exploitation. As a way to combat the dwindling

populations, macaw preservation techniques have been implemented in some South

and Central American locations. The Tambopata Macaw Project in the Madre de

Dios region of Peru has been the leading force of this macaw conservation effort.

Their efforts at supporting the proliferation of this species have included the

protection and management of macaw habitat, the construction of artificial macaw

nests, and the hand-rearing of macaw chicks in captivity for later reintroduction into

the wild. The increasing level of human contact with the ecology of macaw species in

Tambopata, Peru has raised some concerns about how beneficial artificial breeding

and rearing strategies are to the overall conservation of macaws. In this paper, the

negative and positive effects of artificial strategies of macaw conservation taking

Blue-and-yellow Macaws at the Collpa Colorado

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place in the Tambopata Research Center are analyzed in order to assess whether

increased human care for the macaws in this region of the Peruvian Amazon.

Background:

There are six total genera of macaw: Anodorhynchus, Cyanopsitta, Ara,

Orthopsittaca, Primolius, and Diopsittaca, all of which are native to Central and South

America, parts of Southeastern Mexico, and formerly the Caribbean. Their relatively

large size, long protruding tails, and beautiful vivid-colored plumage mark these

spectacular members of the Psittaciforme (parrot) family. The Neotropical genus

Ara contains the highest number of species, ten, two of which have already gone

extinct. Macaws stand at a high risk of extinction mostly due to both aspects of their

own ecology, including high selectivity for nesting habitat and low reproductive

rate, and anthropogenic influences, namely destruction of habitat by deforestation

and the illegal pet trade.

The intricate designs of

the macaws distinguish them

from the rest of their parrot

family. Both their colorful

feathers and distinctive facial

patch are said to be as unique

as a fingerprint. However,

these differences are so subtle

that two macaws are virtually A scarlet macaw perches itself on a bed in one of the TRC rooms. Photo by: Robert Chun

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indistinguishable from one another. The size range for Macaws varies from the

smallest species, the Red-shouldered Macaw, or Hahn’s Macaw (Diopsittaca nobilis),

of 30-35 cm in length, to the largest, the Scarlet Macaw (Ara Macao), of 81-96 cm in

length. More than half of a macaw’s length is attributable to its long, graduated tail,

which, along with its impressive wingspan, makes it an apt, agile flyer with the

ability to reach speeds up to 56 kilometers per hour. Macaws have zygodactylous

feet, with two toes pointing forward and two pointing backward, which, functioning

like hands, allow them to easily grasp food and bring items to their mouths, as well

as sturdily perch onto and walk about tree branches.

Unlike most large birds, macaws are not birds of prey, but rather generalist

herbivores (Gilardi, 2012). Other than a trace amount of snails and insects, their diet

consists mainly of fruits, berries, palm stems, flowers, nectar, foliage and nuts found

in their rainforest environment. Their powerful angular beaks, with estimated bite

strength up to about 500-700 psi, support the macaw’s diet, allowing them to break

open even the toughest Brazil nut shells with ease. Their dry, scaly tongues actually

contain a small bone that allows it to function almost as a tiny finger, a useful tool

for licking off morsels of food into their beaks. As a way of decreasing dietary

competition, macaws tend to forage on unripe fruits and tough nuts that are too

difficult for most other creatures in their habitat to eat.

In the lowlands of the Peruvian Amazon (the focus for this paper), many of

the under-ripe fruits and nuts present in macaw diet contain toxins and other

caustic materials that plants have adapted as physical and chemical defense

mechanisms. The ability to digest these toxic fruits allows the macaws to exploit an

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abundance of foods rich in nutrients, throughout both rainy and dry seasons

(Gilardi, 2012). While the macaws are able to digest these substances, they can

cause severe dietary issues if ingested in large quantities. As a way of neutralizing

these toxins, macaws eat sodium-rich clay off of riverbanks, also known as “collpas”

or “clay licks,” which neutralize these

toxins; the clay particles actually bind

together with the toxins, preventing

absorption of the toxins, which are

passed out with fecal matter

(Brightsmith, 2003). While the clay

from these macaws’ diets are rich in

antioxidants, the macaws seem to be

more drawn to clay with higher sodium

content rather than higher antioxidant content (Powell et al. 2009). These findings,

as well as evidence of macaws feeding on salt from salt mines, have lead to theories

of sodium craving in Macaw diet. Whether it is for antioxidants or satisfaction of a

salty appetite, macaws are driven to congregate at clay licks almost daily, with a

strong influence on weather conditions and breeding conditions (Brightsmith,

2004).

The Convention on International Trade in Endangered Species of Wild Fauna

and Flora (CITES) has listed 7 species of macaw on their Appendix II, which lists

species that aren’t necessarily threatened with extinction, but have a high risk of

becoming extinct unless trade is closely monitored. Appendix I, which lists species

The Collpa Colorado clay lick near the TRC, where the macaws congregate to eat the sodium-rich clay.

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that are most critically endangered and threatened with extinction, contains 11

species of macaw, 3 of which (the Blue-headed macaw, the Red-fronted macaw, and

the Scarlet macaw) are endemic to the Tambopata region.

One of the main drivers of the dwindling populations of macaws is their

naturally low reproductive rate. Macaws are generally highly selective of their

nesting habitat, preferring deep, dry nest cavities on old growth trees that only

occur at abundances of about one per 12-20 hectares of rainforest habitat. This

selectivity for suitable habitat makes it difficult for macaws to nest and fledge

young. Even when the macaws do nest, usually only a small fraction of their eggs

survive, due to predation of the eggs by jays, crows, and toucans. Even if eggs

survive to hatching, the parents will often only care for and feed one or two of these

eggs (usually the strongest of the fledglings), leaving the smallest to die of

malnutrition.

While the naturally low reproductive rate puts macaw populations at a

disadvantage, the largest drivers of their endangerment are anthropogenic: namely

the destruction of habitat and exploitation for the pet trade. With agricultural slash

and burn, urbanization, and projects like the Southern Interoceanic Highway, Peru’s

deforestation rate has increased significantly from 0.14 percent in 2005 to 0.22

percent in recent years. The Interoceanic Highway, which was completed in July

2011, cuts across the Tambopata reserve and has destroyed a great deal of

ecosystem and biodiversity in this region. In addition to projects like these, selective

logging in the Peruvian Amazon often targets the scarce old growth trees that

macaws rely on for nesting.

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While CITES lists the vast majority of macaw species as illegal to trade, lack

of enforcement of these regulations has led to the proliferation of trade of

endangered species. In Bolivia, a powerhouse in the South American bird trade, a

monitoring of the parrot pet trade from August 2004 to July 2005 found that 94% of

parrot individuals were believed to have been caught in the wild and several species

present in the trade were listed as endangered, such as the Hyacinth Macaw, the

Blue and Yellow Macaw, and the Scarlet Macaw (Hennessey and Herrera, 2007).

This study, which shows the high level of illegal parrot trade in Bolivia, suggests that

this is probably true for Peru and other receiving markets of the trade, such as

Brazil. In the illegal smuggling of illegally traded macaws, 90% of macaws do not

survive because of hazardous conditions of transportation. The going rate for a rare

species of macaw can be as high as $50,000 in the illegal trade market. One estimate

by the United Nationals Environment Programme priced the annual illegal

contribution of the pet trade in between $5—8 billion. (Oldfield, 2002, page 13).

These high prices provide large incentives for illegal traders, especially when

penalties are minimal to non-existent.

These threats to macaw populations led Eduardo Nycander to start the

Tambopata Macaw Project in 1989, with the aims of gathering data on the ecology

and natural history of macaws in order for conservation applications. The project is

located on the Tambopata River at the center of a large reserve site in the Madre de

Dios Region in Peru, surrounded by acres of pristine rainforest. This project led to

the construction of the Tambopata Research Center in order to house the project’s

research team. As Nycander began to concentrate on establishing the ecotourism

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company Rainforest Expeditions, as a way of ensuring funding for the Tambopata

Research Center, he passed on leadership of the project to Donald Brightsmith of

Texas A&M University.

Since his acceptance of the TMP torch, Brightsmith has taken the level of

macaw research to new heights, publishing countless works on his team’s firsthand

observations of macaw behavior, physiology, breeding habits, and phylogeny. The

location of the Project in the Peruvian Amazonian basin is ideal for macaw research,

with the largest known macaw clay lick, the “Collpa Colorado,” just down the river

from the TRC’s port. The research done at this frequently visited clay lick has led to

newfound information for over 15 different species of macaws. In addition, several

different macaw breeding projects

have been implemented in order to

bring up the dwindling population

numbers. The new focus for the

project under Brightsmith is aimed

at providing opportunities for

satellite projects in other South

American countries to spread the

conservation efforts of the TMP to

other areas of threatened macaw

habitat.

Some of the breeding

Two of the scarlet macaw "Chicos" greet an eager TRC visitor.

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strategies that the TRC has inaugurated include various breeding and rearing

strategies to introduce increase numbers of macaws into the wild, as well as the

construction of artificial nesting sites to promote natural breeding. In 1991,

Nycander led a project in which 30 macaws were hand-raised and released at TRC;

these “chicos,” as the TMP team knows them now, still make frequent visits to the

TRC. The artificial nesting strategies range from cutting the tops of palm trees in

order to promote natural decay for cavity (nesting) formation, to altered PVC pipes

being hung from trees. The effectiveness of these different nesting and breeding

techniques will be the focus of this paper.

Hypotheses:

While the aims of the Tambopata Macaw Project are at benefiting the

populations of macaws, the more hands-on strategies they have implemented have,

to an extent, broken the barrier that has existed between man and macaw. From

hatching to habitation, the nature of macaws of this region has been altered by the

TMP’s researchers, which draws in the risk of natural ecological disruption and

human dependency. Such concerns have led to the two hypotheses of this project:

1. The strategies for macaw nest construction that better mimic the natural

ecology of the species are more beneficial to the conservation of the species

than more artificial approaches.

2. Artificial breeding is less successful than natural breeding because it

interferes with the chicks’ ability to develop familiarity and behavioral

adaptations to their natural environment, establishing a dependency on

human care for their survival.

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Findings:

Nesting Strategies:

The first successful artificial nest boxes were created at the TRC in 1990. The

nest boxes were made from Ireartea palm trunks and were inhabited by wild

macaws. This resulted in the scarlet macaw (Ara Macoa) being the first species to

fledge young one of the nest boxes. However, these nest boxes were not sustainable,

in that they rotted away in less than two nesting seasons. A new nest box made

from cedar wood was tested in 1992, and proved to last longer than the palm trunk

nest boxes, but still rotted away very quickly (Brightsmith, 2000).

This led Eduardo Nycander to design the first PVC nest box in hopes to be

both successful and durable for macaw breeding. The boxes had tropical cedar tops

and bottoms to more closely mimic the natural tree nests. The results showed that

out of five nesting boxes, scarlet macaws used four in the 1992-1993 nesting season.

In 1999, the nest box designs were refined, replacing the wooden tops and bottoms

(which rotted away) with metal disks. That year 12 boxes were set up for scarlet

macaw habitation, nine of which were used for nesting. Based on the success of

these boxes, plans began for new artificial nest boxes specially designed for

habitation by other species of macaw and durability in their natural habitats.

(Brightsmith, 2000).

In 2006, Donald Brightsmith conducted an experiment in which artificial PVC

nest boxes were hung in live palm trees in order to increase the nesting sites for

blue-and-yellow macaws. The nest boxes were hung in the palm swamps near the

research center, where blue-and-yellow macaws naturally nested. The palms of this

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area, Mauritia flexuosa, have been known to be significant nesting resources for

macaws for both the abundance of fruit it produces and the cavity it forms when the

palm dies. The PVC pipes were left opened at the top to mimic the naturally

occurring cavities of the palms, themselves. The habitation of these artificial nest

boxes was then compared to the

habitation of natural nests in that area.

Their results showed that blue-and-

yellow macaws did not use any of the

artificial PVC nest boxes in the swamp

and the birds were not seen entering the

PVC nest boxes. Less than ten miles away,

33 blue-and-yellow macaw nests were

observed in dead M. flexuosa palms.

Brightsmith suggestes that “thermal characteristics, shape, drainage, or other basic

characteristics of the PVC nests were unacceptable to the blue-and-yellow macaws”

(Brightsmith, 2006).

In the same study, another attempt to promote blue-and-yellow macaw

nesting was conducted in which the tops of the M. flexuosa palms were cut off,

leaving the palm to slowly rot away, more accurately mimicking the natural nesting

habitat of the macaws. 12 blue-and-yellow macaws made nesting attempts in these

cut palms. In one nest, the bottom of the nest collapsed, destroying the eggs that

were there. In another, a chick hatched from an egg, but was depredated and did not

survive. In six nests, one chick fledged and survived. Four other nests were habited

One of the wooden design nest boxes at the TRC. photo by: Marika Jaeger

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by macaw pairs, but did not fledge any chicks. While the cut palms seemed to

provide a better nesting habitat for blue-and-yellow macaws than the PVC nest

boxes, the palms had an average lifespan of about four years, after which time the

palms would fall over. In swamps with naturally dead palms, this is also the case,

but 1% of the palms in these swamps die per year, so as dead palms fall every four

years, more palms die, producing new suitable nesting sites. Brightsmith concluded

that in order for such a managed swamp to be successful, a 100-year rotation cycle

would have to be implemented, in which palms are cut and regrown (Brightsmith

2006).

Data from hundreds of blue-and-gold, red-and-green, and scarlet macaw

nesting observations was collected by the TRC to compare the effectiveness of

natural, PVC, and wooden nest structures. These results showed that Natural nests

had a 65% success (hatching of chicks) rate, while the PVC nest boxes only had a

success rate of 41%. The wooden nest boxes were not inhabited by enough macaws

to draw significant conclusions (Brightsmith, 2003).

Artificial Rearing Strategies:

In 1994, in order to gain a better understanding of the comparative health of

captive macaws and wild macaws, a health survey of parent- and hand-reared

scarlet macaws was conducted in the Tambopata-Candamo Reserve Zone in

Southwestern Peru. The physical examination for the birds consisted of blood

samples being analyzed for diseases. The results of this examination showed that

the hand-reared macaws were more susceptible to Salmonella. Those that tested

positive for Salmonella were known to have visited the TRC on a frequent basis. The

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birds were suggested to have contracted Salmonella in the kitchen of the lodge,

where chickens have been known to have been brought on multiple occasions

(Karesh, 1997).

In 2005, a collaborative study was done by Donald Brightsmith et al. on the

use of hand-raised scarlet macaws for reintroduction in Peru and Costa Rica. In this

study, 20 younger chicks were removed from natural and artificial nests in

Tambopata at age 5-15 days. Many of these chicks were from nests with 2-3 chicks,

and would not have survived naturally due to malnutrition associated with

preferential parenting. The chicks were taken and incubated at the TRC, after which

they were hand-raised in small boxes. No effort was made to isolate these chicks

from human contact. As the birds grew, little to no pre-release training for the

chicks occurred. The birds were not held in cages, so releases happened naturally, as

individual fledging birds flew into the forest 80-100 days after initial removal from

the wilderness. The birds returned to the lodge to be fed within a range of 12 hours

to 3 days.

Of the 20 macaws that were released, 74% survived their first year. Of that

74%, 96% survived the next year. As of March 2002, 55% of the original hand-

reared individuals were still alive, even despite the threat of 5 known raptor species

that widely predate this area. The naïve birds were assumed to have learned both

feeding and survival techniques from the surrounding wild populations. The

released birds showed no fear for humans, and even returned regularly to the TRC

for food. At the TRC, the supplemental feeding actually promoted social interactions

among the flock members. This establishment of flock cohesion helped the released

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birds effectively alarm call at the sight of predators and return to the lodge for

safety.

Conclusions:

After further research and comparative analysis of the results, the original

hypothesis that “the strategies for macaw nest construction that better mimic the

natural ecology of the species are more beneficial to the conservation of the species

than more artificial approaches” has been found to have been plausible and

supported. As shown by the data, macaws have been observed to prefer their

natural nests over artificial nests, often times leaving artificial nests uninhabited.

Historically, artificial nests made from palm trunks and decapitated Mauritia

flexuosa palms have had better success in terms of macaw habitation and

reproduction than the more artificial PVC and wooden nest boxes.

However, even though these more natural nests were preferred (thus

habited) by the macaws, they were definitely not as durable or sustainable as the

more artificial PVC nest boxes. Therefore, it is arguable that if the PVC boxes were

somehow made to be more favorable to the macaws, they would be more beneficial

to macaw conservation, since they would be more sustainable than the natural

nests.

In addition, the second hypothesis that “artificial breeding is less successful

than natural breeding because it interferes with the chicks’ ability to develop

familiarity and behavioral adaptations to their natural environment, establishing a

dependency on human care for their survival” has been refuted by further research.

In actuality, artificial hand-rearing can actually allow for a higher survival rate of

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total chicks from one nest, especially in cases of nests with multiple eggs, since on

average only one chick would receive proper nutrition from parents, leaving the

others to die of malnutrition. However, increased human contact also increases the

risk of exposure to diseases like salmonella, which necessitates more controlled

rearing practices.

As exemplified by the “chicos” of the TRC, hand-reared chicks can survive to

fledging age and be reintroduced into the wild. Although these hand-reared macaws

do return to the lodge for an easy meal, they are able to survive in the surrounding

wilderness on their own, probably learning from other wild members of their

species essential survival techniques. In addition, supplemental human contact after

reintroduction of the macaws can actually promote social behavior, which in tern

promotes flock cohesion, mating, and protection from predation. However, one

might argue that these results might be different if the area of study was not

protected from poaching and pet trade, as is the case in the vast majority of non-

reserve macaw habitat. Such threats urge wariness for the degree to which exposure

to human contact is helpful to macaw conservation in different settings.

Acknowledgments:

This study would not have been possible without the Sophomore College

Program, particularly the course: Conservation and Development Dilemmas in the

Amazon. I would like to thank Professor Bill Durham and Professor Julia Novy-

Hildesley especially for organizing this course and teaching us so much about the

ecology, resilience, policies and indigenous cultures at the heart of the dilemma

surrounding the Amazon. I would also like to thank Rainforest Expeditions for their

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wonderful hospitality and for providing our group with a phenomenal set of

informative guides. A special thanks also to John Sutherland and Karen Alderete for

their great attention to detail in all aspects of this course’s logistics. Additionally, I

would like to thank Marika Jaeger and Robert Chun for their photographs that

appear in this paper. Lastly, I would like to thank all of the students and alumni who

participated in this course, whose vivacious and exploratory personalities made this

experience incredible on so many levels.

Works Cited

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28(3): 24-32.

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Federico Guillen. 2005. The use of hand-raised Psittacines for reintroduction: a case

study of scarlet macaws (Ara macao) in Peru and Costa Rica. Biological Conservation

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