chapter 1-3 (with border).docx
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1University of Santo Tomas College of Science PAGE
CHAPTER 1
Introduction
1.1. Background of the Study
Biological invasion is a major cause of ecosystem disruption and biodiversity loss
(Albins & Hixon, 2011). It is a global problem which has great impacts that can be of great
magnitudes (Arguelles & Zilletti, 2005). Biological invasions happen when organisms are
introduced into a new ecosystem, either intentionally or unintentionally. These organisms,
referred to as invasive species, may cause drastic changes and more often than not, damages
to the new environment they are introduced in. Loss of native biological diversity and
extinction of native populations are some of the presupposed damaging ecological
consequences of species invasions.
In a renowned Philippine lake, the Laguna de Bay, there is a growing concern on the
lake being besieged once again by another type of aquatic invasive species. Laguna de Bay is
the largest lake in the Philippines and is situated between the provinces of Laguna and Rizal.
The Philippines‘ largest inland body of freshwater is an abode of a variety of organisms
comprising its biodiversity pool.
The invasive species of the lake comprises 70 percent of the fishermen‘s catch, and is
believed to be a Chitala ornata species. The fish species is known by different names
including Clown knifefish, Spotted knifefish, and Clown featherback.
Chitala ornata invasion is the second biological invasion that took place in the lake.
The lake was previously invaded by the suckermouth catfish, or locally known as the ―janitor
fish‖. The janitor fish has no known predator, which is why they easily proliferated and
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outnumbered the native fishes in Laguna Lake. Recently, another type of invasive species,
Chitala ornata, is creating havoc in the said lake. It is uncertain if the said species could have
escaped or could have been intentionally freed as a result of aquarium releases (Cinco, 2012).
The Clown knifefish Chitala ornata is characterized by its silver gray coloring, with
large spots of variable patterns above the base of its anal fin. It bears a flat and elongated
body with an arched back. Its anal fin and caudal fin are joined, giving it a long, continuous
body. Owing to its sword-like appearance, the clown knifefish is one of the most favorite
ornamental fish species of fish hobbyists. They are found in freshwater bodies in Southeast
Asian countries such as Thailand and Burma. Belonging to the Order Osteoglossiformes,
Chitala ornata species are considered one of the most primitive of the modern teleosts. The
term bonytongue describes a trait shared by all members of the Order Osteoglossiformes;
well-developed tooth-like tongue bones that bite against teeth on the roof of the mouth
(Cooke & Bruce, 2004). The Clown knifefish species are believed to be carnivores (Hargrove
& Hargrove, 2006). In their natural habitat, they are primarily piscivorous preying on other
fish species.
To date, amount of prey consumption and selection of Chitala ornata species in
Laguna de Bay have not been investigated; although local news have reported that these
fishes feed on indigenous species inhabiting in the lake, leading to a decline in the catch of
economically important fishes like tilapia and bangus (milkfish). Early efforts to assess the
density of Clown knifefish in Laguna de Bay by the Bureau of Fisheries and Aquatic
Resources (BFAR) reported that the Clown knifefish populations were rapidly increasing,
displacing the native species of the lake.
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1.2. Statement of the Problem
The invasion of the predatory knifefish in Laguna de Bay is alarming. It terrorizes the
biodiversity of the once remarkable lake. It does not only spawn environmental harm, but
also of economic harm. The local fishermen have raised their concerns on the negative
effects of the invasion in their livelihood.
The rationale of the study is to determine the feeding ecology, specifically, to
examine prey selection, quantity of consumption, and the ability of Chitala ornata species to
endure starvation. Moreover, the study addresses the following specific questions:
1. Is there a relationship between prey size and selection in three size classes of
Chitala ornata?
2. What is the prey range in Chitala ornata found in Laguna de Bay?
3. How much is the food consumption per unit time in different sizes of Chitala
ornata?
4. Is there a significant difference on the prey consumption in three size classes of
Chitala ornata?
5. How much is the energy conservation in the three size classes of Chitala ornata
during periods of starvation?
6. Is there a significant difference on the conservation of energy in different sizes of
Chitala ornata during periods of starvation?
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1.3. Objectives of the Study
This study will focus principally on the species of Chitala ornata, which will be
gathered from Laguna de Bay, Philippines. The feeding ecology of the said invasive species
will be studied through experiments and observations in the laboratory. Thus, this study
aims:
1. To determine the relationship between prey size and selection of Chitala ornata;
2. To determine the fish species found in Laguna de Bay that the Chitala ornata
species are eating;
3. To know the quantity of prey they consume per unit time; and
4. To determine the ability of Chitala ornata species in withstanding periods of
starvation.
1.4. Significance of the Study
The information that will be obtained by the researchers from the study will surely be
a vital and useful knowledge on the subject of feeding ecology in Chitala ornata, in addition
to the already acknowledged facts concerning the nature of the said fish species. The findings
from the experiment can be utilized by different sectors, agencies like BFAR, academic
institutions, as well as the local fishermen of Laguna de Bay. Moreover, the results of the
study will certainly be of help to the researchers and scientists who are studying Chitala
ornata, and to the future researches as well. Lastly, the study will aid in better understanding
the themes relating to ecology and biodiversity.
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1.5. Scope and Limitations
The study will be focusing primarily on the feeding ecology in Chitala ornata (Clown
knifefish). It will cover the following areas of study: prey selection, consumption, and its
capacity to withstand periods of starvation. The live prey fish that will be used for the
experiments and observations on prey selection and consumption is Tilapia (Oreochromis
sp.) of various sizes. The laboratory set-ups for the experiments and observations of the study
will be assembled and accomplished at the University of Santo Tomas. It is expected that the
researchers will finish the experiment within a span of 5 months. The results and information
that will be obtained from the study may be directed to the agencies/institutions like BFAR,
to the academic community, and the fishermen of Laguna. The research does not cover any
other areas of study apart from what is stated, specifically on the subject of eradication of
these invasive species on Laguna de Bay.
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CHAPTER 2
Review of Related Literature
2.1. Biological Invasion
Biological invasions are increasing on a global scale and have become an issue of
critical importance because of their real and potential impacts on both marine and freshwater
ecosystems (Heinonen & Auster, 2012). Such invasions consist of complex processes and
phases such as transportation to a new region, release or escapement in the wild, dispersal or
spread and finally, its relative impacts in its new environment. Invasive alien species are non-
native species in a new environment that have spread beyond and become abundant. Species
invasions are believed to be increasing, and are now recognized as one of the main threats to
biodiversity and one of the drivers of global change. Not only species invasions affect
biodiversity, such species may act as vectors for new diseases, reduce biological
productivity, degrade habitat structure, and alter food webs through ecological processes
such as competition and predation (Heinonen & Auster, 2012). The decrease or elimination
of native populations causes negative impacts on ecosystem functions, and even enormous
economic effects. In addition, freshwater ecosystems and fish taxa are mostly affected by
introductions. An example of such introduction of non-native species is the invasion of lion
fish Pterois volitans in the Bahamian archipelago leading to a decrease in the number of
Bahamian coral-reef fish communities. Although extinction is the most common result of
invasions, there are other ecological and evolutionary impacts of biotic homogenization that
are less understood thus, prevention and precautionary principles are of particular relevance
to invasive species (Clavero & Berthou, 2005).
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Invasions on biological systems are worldwide ecological events, although their
mechanisms are still not clearly understood. Invasive species create negative impacts on
endemic species and ecosystems they are introduced in, through competitions, predations,
altering habitats, and dispersing diseases. They pose an escalating hazard to the composition
and structural aspects of natural communities across the globe. Biological invasion has been
injurious to the ecological and evolutionary integrity of natural ecosystems to a great extent,
which causesthe deterioration of the functions of the ecosystems, and recurrently causes
natural adversities. An enhanced knowledge of the origins, patterns, predictability, outcomes,
and management preferences concerning this threat to our biodiversity is a vital tool to direct
managers, policy makers, researchers, and the general public. Biological invasions cause
enormous economic losses. A statistical analysis stated that at least 137 billion dollar losses
annually from biological invasion were estimated in USA. Invasive diseases, another result
of invasions, weaken human health and can take the lives ofmany people. Biological invasion
for the most part diminishes global biodiversity, which will menace the survival
and development of the succeeding generations (Xie, et. al., 2003). There really are a number
of harmful and negative effects of biological invasions so it is necessary to examine and
make researches regarding the invasive species which cause these global invasions.
2.2. Invasive species
The Center for Invasive Species and Ecosystem Health defines the term ―invasive
species‖ as any non-native or alien biological species (including seeds, eggs, spores, or other
propagules), and whose introduction to an ecosystem causes or is likely to cause economic
harm, environmental harm, or even harm to the human health. These invasive species grow
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and reproduce very fast, resulting to a major disorder to the ecosystems in which they are
present ("Invasive species 101," 2012).
The grounds of the crisis on invasive alien species are chiefly economic and thus, it
also require economic solutions. The subject on invasive alien species is gaining a high
concern for four main reasons. First, biological invasions are increasing rapidly whilst the
mechanisms and plans for eradication of these foreign species have been either inhibited or
totally failed. Second, the costs of these invasions are growing quickly owing partially to the
augmenting human population density, and to some extent, to the rising intensity of
production in genetically impoverished agricultural systems. Third, invasions are related with
a high degree of ambiguity because they both involve new interactions and for the reason that
biological invasion risks are endogenous. Lastly, the elimination and management of these
invasive species are a "weakest-link" public good. According to the Convention on
Biological Diversity (CBD), it defines invasive alien species (IAS) as organisms that are
introduced to a certain ecosystem. They now establish, grow naturally, and multiply outside
of their habitat range, and whose impacts entail significant harm on economy and even the
human community. Biological invasions make threats on societies in at times critical ways;
for instance, the spread of HIV infection in southern Africa. Economics aids in the
identification of the social causes generated by biological invasions, and therefore develop
institutions and mechanisms capable of solving them (Perrings et al., 2002). In a recent
species invasion in the Philippines, one of its inland bodies of water is invaded by an aquatic
dweller. This invasion is the second account of species invasion in the freshwater lake.
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The problem on the subject of invasive species is of much interest to researchers in a
wide array of diverse fields including Biological Science, Epidemiology, Agriculture, Public
Health, Human Sciences, and other fields of Science. This topic is of great importance for it
concerns the whole world to a greater or lesser degree (Pastoret & Moutou, 2010). Academic
works and researches concerning the topic prove to be a key in better understanding the
biodiversity of the diverse ecosystems in our world; and moreover, to address the problems
generated by these invasive species.
2.3. Laguna de Bay
2.3.1. Biophysical Features
Laguna de Bay, also known as Laguna Lake, is the largest lake in the Philippines and
the second largest freshwater lake in Southeast Asia. Located on the island of Luzon, the
Laguna de Bay watershed cuts across five provinces, 66 municipalities and 9 cities including
parts of metropolitan Manila (Oledan, 2001). The lake provides livelihood to fishermen of
Laguna and Rizal provinces, and supports some 9,000 ha of fish pens and fish cages (Palma,
Diamante & Pol, 2002). In the past, humans used Laguna de Bay mainly for fishing industry,
which helps in providing an important source of livelihood for the local population. Through
the years, Laguna Lake has become an important source of water for agricultural,
commercial, and domestic use. Until the 20th
century, the lake served as a waste disposal site
for all of these human activities Thus, the lake gives important sources of livelihood for the
local communities. Through the years, Laguna Lake has become an important source of food,
water for irrigation, power supply, cooling of industrial equipments, and a source of raw
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water for domestic supply. During the winter season in other parts of the world, Laguna de
Bay serves as a shelter for migratory birds and a place for food hunting.
The evolution of the lake was defined by at least three major paleosalinity shifts that
occurred over the past 6,000 years (Jaraula, 2001). The lake evolved from brackish water to a
marine and ultimately, to a freshwater by the changes in the sea level and tectonic plates. The
lake‘s water turbidity is due to the high surface area to volume of water ratio. The
Philippines’ Department of Environment and Natural Resources (DENR) classifies
Laguna de Bay as a Class C fresh surface water. Having a Class C type of water means it
is adequate for the propagation of fishes and other aquatic resources, non-contact
recreational purposes such as boating and jet skiing, and as a source of industrial water
(DENR, 1990). Being a Class C type of water body, its pH lies between 6.5-8.5, along
with nitrate and phosphate content of 10 mg/L and 0.4 mg/L, respectively (Santos-
Borja, 2006).
2.3.2. Biodiversity and Fishery
Aquaculture is an important factor in the fishery of Laguna de Bay in the Philippines.
Fish pens and net-cages covered 10% of the lake surface in the late 1990s. Aquaculture
became a very profitable lake-related business suggesting the culture of other species (e.g.,
tilapia; bighead carp , Hypopthalmichthys nobilis). A stock assessment of major fishery
resources showed the open water catch is composed of 13 species, including the shrimp
commonly found in the lake (Palma et al., 1997). Among the fish species commonly caught
were Oreochromis sp., H. nobilis., and A. manilensis. For phytoplankton, the most common
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are the blue-green algae and diatoms. One study shows that the phytoplankton group in
Laguna de Bay consisted of the blue-green algae Sprirulina major and Lyngbya limnetica,
green algae Chlorella vulgaris and Pediastrum sp., and for the diatoms, Bacillariophyta
(Delima & Baldia, 2012). From May to September, abundance of phytoplankton is generally
observed. Also, alarming levels of algal blooms can be observed during these months which
are often dominated by Microcystis sp.
Laguna de Bay used to be a home for 23 freshwater fish species. However, due to the
ineffective flood control structure and destructive government-sponsored, foreign-funded
development projects around the lake, only 6 species survived. Some of the species that were
endangered include martiniko (climbing perch), igat (eel), talakitok (carynx), biyangbato
(rock goby), kansuswit (halfbreak), biyangtulog (sleeping goby), biyangputi (white goby),
buan-buan (tarpon), bulong (goby), talilong (mullet), dalag (snakehead), papalo (sneaker),
tawes (tawes), kitang (spade fish), baliga (eel goby), plasid (snakehead), and another kind of
plasid known as three spot. Presently, there are no recorded endemic species in Laguna de
Bay, probably because it is very young lake, formed 6,000 years ago. Its link to Manila Bay,
and the introduction of non-native species, also could have contributed to this phenomenon
(Santos-Borja, 2006). To date, an additional cause of the decrease in number of native
species is the invasion of another aquatic species, like the Chitala ornata or Clown knifefish.
2.4. Chitala ornata
2.4.1. Biology
The Clown knifefish (Chitala ornata) is a tropical (24°C - 28°C) freshwater fish,
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under the Class Actinopterygii, Order Osteoglossiformes, and Family Notopteridae. It is an
indigenous fish of several Asian countries including Cambodia, Indonesia, Laos, Thailand,
and Vietnam; inhabiting flowing waters of large and medium-sized rivers. It is distinguished
from other members of the family by the existence of a row of large ocellated spots above the
base of the anal fin. It is a piscivorous type of fish, preying on surface-feeding fishes,
crustaceans and insects alike, with a crepuscular or nocturnal activity pattern. A mature
Clown knifefish can reach a maximum length of 100.0 cm and a maximum published weight
of 4,950 g ("Chitala ornata," 2012).
2.4.2. Ecology
Chitala ornata is known to different names: Clown featherback (English), Trey krai
(Khmer), Pa tong khuai (Lao), Pla tong krai (Thai), and Ca com (Vietnamese), among many
others. This fish is found dwelling extensively in mainland Southeast Asia. It is a
carnivorous, night-active (crepuscular) type of fish, feeding mainly on other fishes,
crustaceans, and even insects. Similar to its congenera, Chitala blanci, its spawning habitats
are established on inundated woods from March to July, with the female fish guarding the
fry. According to Smith (1945), after spawning, the female departs and the male takes in
charge in safeguarding the eggs. Chitala ornata is reported to have been migrating locally
into smaller tributaries and flooded areas during flood season and return back to the main
river channel when the flood has already subdued. A number of fisher folks have said that the
habits and spawning of Chitala ornata as well as Chitala blanci were the same on the
mainstream. Observations on the spawning habits of the two featherbacks have been made in
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Loei, Paksan, Nakhon Phanom, and Ubon Ratchathani provinces in Thailand. Large
individuals of featherbacks have been standard goods at local markets throughout its range.
Chitala ornata is more commonly seen than its congenera, Chitala blanci. They are chiefly
caught by gillnets, and hook and line. Furthermore, Chitala ornata is a prominent facet in
aquarium trade (Poulsen et al., 2004).
2.4.3. Invasion in Laguna de Bay
As represented by different articles with reference to the invasive species, the
mechanism of invasion is two-fold. It may either be natural or deliberate. In the case of the
invasion of Chitala ornata in Laguna de Bay, the incursion is caused by either one of these
two: (1) the fish could have escaped or else, (2) it could have been intentionally freed. Some
sectors accept the first theory, in which the knifefish might have escaped from fish farms
during the flood generated by tropical storm Ondoy in 2009. On the other hand, others
consider the latter theory. They suppose that the propagation of Chitala ornata could have
been done by knifefish hobbyists who released the fishes in the waterways when the fishes
have grown too large to be kept on the aquariums; an idea similar to that of the proliferation
of the overtaken suckermouth catfish (commonly known as ―janitor fish‖) in the previous
years. Both fishes were known to be introduced in the Philippines as ornamental fishes
(Galvez, 2012).
2.4.4. Effects of Chitala ornata Invasion
According to an article of The Manila Times entitled ―New ‗monster‘ species out to
ruin Laguna Lake‖ published last May 19, 2012, an invasive predator known as the
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―knifefish‖ is now threatening to wipe out the biodiversity of the country‘s largest lake —
Laguna de Bay. An alliance of fisher folk and stakeholders has asked the Laguna Lake
Development Authority (LLDA) to investigate what they call the ―invasion of the predators,‖
which are now spreading in a very rapid pace, preying on the different native species found
in Laguna lake. A number of groups including Pambansang Lakas ng Kilusang
Mamamalakayang Pilipinas (Pamalakaya), Save Laguna Lake Movement (SLLM) and
Anakpawis party list, have staged a fluvial protest to call the attention of the local
government to take action on the problem regarding the invasion of the knifefish.
One article from Phili ppine Daily Inquirer entitled ―Knifefish threatening native
species in Laguna Lake‖ issued on May 21, 2012, reported the consequences of the invasion
of the predator. According to Bureau of Fisheries and Aquatic Resources (BFAR), the rapid
multiplication of the invasive species is displacing the native species of the lake. The
fishermen‘s groups of Laguna de Bay have complained that their catch of native fishes
including tilapia, bangus (milkfish), martiniko, igat (eel), dalag (mudfish), biya (goby), and
ayungin (silver perch), is shrivelling, with their income threatened because the citizens were
not accustomed to eat the foreign fish. In the long run, it is not impossible that the indigenous
fishes found in Laguna de Bay will go extinct.
Because of the different negative effects resulting from the invasion of the infamous
knifefish in Laguna de Bay, different proposals for action are made to address the growing
problem. BFAR has proposed a plan of collection and harvest of the knifefish eggs in order
to impede the production of the invasive species. The objective is to get rid of the clump of
eggs, numbering to several thousands of fry, resulting to a significant decrease in the
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population. This plan was based on the findings made by the agency‘s National Inland
Fisheries Technology Center, which demonstrated how knifefish could spawn naturally in the
lake and its eggs stick to the bamboo poles and stakes of fish pens and cages owned by the
local fishermen. BFAR has worked in partnership with the Laguna Lake Development
Authority (LLDA) to better address the problems plaguing the country‘s largest lake and
which affect the livelihood of the local fishermen (Salaverria, 2012).
2.5. Biodiversity
As stated earlier, one of the many dilemmas on the invasive species is undoubtedly
linked to the subject of biodiversity. For example, The International Union for the
Conservation of Nature (IUCN) has instituted the so called ―Red List of Threatened Species‖,
which is generally recognized as the most comprehensive, objective global approach for the
evaluation on the conservation status of diverse biological species. The list includes attributes
like: Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN),
Vulnerable (VU), Near Threatened (NT), Least Concern (LC), Data Deficient (DD), and Not
Evaluated (NE). Many of these biological species are threatened by the invasive species and
other human-related factors. Human beings are, and always have been, the cause of many, if
not most, of the biological invasions (Pastoret & Moutou, 2010).
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CHAPTER 3
Materials and Methods
3.1. Transportation and handling of specimens
Clown knifefish of various sizes will be captured in Laguna de Bay by the local
fishermen. After capturing, the fishes will immediately be placed in separate containers with
slightly salty water (1-2% NaCl), and will be anesthetized lightly (Sukumasavin, 2007).
Tricaine methanesulfonate (MS-222) will be used for anesthetizing the fishes through
immersion at 100-200 mg/L dosage (Cruz-Lacierda, Dela Pena & Lumanlan-Mayo,
2000).Oxygen will also be provided for the fishes because of the long amount of time of
transportation from Laguna to University of Santo Tomas.
3.2. Laboratory set-up
Three size classes of Chitala ornata will be kept in three different aquaria in groups
of five. Small (S) Clown knifefishes with length of 30-35 cm, will be kept in aquaria of 80-
100 L (≈30 gallons), well-aerated, biologically and mechanically filtered. Medium-sized (M)
Chitala ornata specimens with size of 50-55 cm will be kept in aquaria of 190-300 L (≈100
gallons); and large (L) knifefishes of 70-75 cm in size will be kept in aquaria of 300-600 L
(≈200 gallons). The aquaria will be kept at 76oF to 80
oF or 24-28
oC, with pH 6 to 7 and
well-lit with LED moon or lunar lightings (Hargrove & Hargrove, 2006).
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3.3. Experiments and Observations
3.3.1. Prey Selection
3.3.1.1. In captivity
Clown knifefishes will be separated into individual containers based on size, and will
be fed with a mixture of prey (Tilapia) sizes. Live prey fishes are divided to three size
classes: Small Tilapia (S) is 5-10 cm, Medium Tilapia (M) is 15-20 cm, and Large Tilapia
(L) is 25-30 cm. Prey size classes will be offered in either two or three prey size class
combinations. Preys will be available for 24 hrs, after which all prey will be removed and
noted (Juanes & Conover, 1994). The relationship between prey size and selection in Chitala
ornata will be examined.
3.3.1.2. Gut dissection
Approximately 3 Clown knifefishes of each size captured in Laguna de Bay will be
subjected to dissection once a month to know their gut contents in order to support our study.
3.3.2. Prey Consumption
Clown knifefishes of known body length and mass will be fed ad libitum. After 24
hours, any non-devoured prey will then be removed (Fishelson, 1997). The live prey fishes
will be weighed before and after feeding in order to determine the amounts of prey consumed
in three size classes of Chitala ornata.
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3.3.3 Starvation
Following twelve weeks of ad libitum feeding, the Clown knifefish specimens will be
given no food for a period of time to study their ability to withstand starvation. The primary
reason for this experiment is to compare energy conservation in three size classes of Chitala
ornata specimens. Once a week, the fishes will be weighed to the nearest 0.5 g and then will
be again returned to their aquaria (Fishelson, 1997).
3.4. Data analysis
3.4.1. Prey Selection
3.4.1.1. In captivity
All the types of fishes that will be consumed by the Chitala ornata specimens on the
laboratory experiment will be recorded. The data will be tallied based on the size of the live
prey fishes consumed. Size selection data will be analyzed using a Chi-square test to detect
differences from a random choice. The three size class combinations will further be tested by
non-parametric Tukey-type multiple comparison test, in order to detect differences between
pairs of size classes (Juanes & Conover, 1994).
3.4.1.2. Gut dissection
The percent frequency occurrence (% FO) will be used to analyze the gut contents of
the Chitala ornata specimens that will be gathered in Laguna de Bay. The number of each
prey found inside the gut will be summed and will be divided by the total number of non-
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empty stomachs dissected (Hyslop, 1980). Thus, the data will be calculated by using the
formula:
3.4.2. Prey Consumption
The weight (g) of the live prey fishes will be recorded before and after feeding. The
amounts of prey consumed will be determined in three size classes of Chitala ornata, which
is computed as prey consumed (g) = W i – W f , where W i and W f are the initial and final weights
(g) of the live prey fishes respectively. The resulting data from the computations will be
compared to each size of the Chitala ornata specimens in order to know if there exists a
significant difference on the prey consumption in the three size classes of Chitala ornata.
Accordingly, it shall be subjected to One-way ANOVA test. Differences will be considered
to be significant at p <0.05. All data shall be analyzed using SPPS software program for
statistical analysis (Sarkar, Deepak, Negi, Qureshi & Lakra, 2007).
3.4.3. Starvation
The initial weight of the Chitala ornata specimens before the experiment on starvation will
be determined. Their weight will be measured once a week and will be recorded. After the
starvation periods, the loss in body weight of the fish specimens will be computed from week
to week, which is computed as weight loss (g) = (W i – W f )/n, where W i and W f are the initial
and final weight (g) of all the fishes in an aquarium respectively, and n is the number of
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fishes in an aquarium (Wang, Hayward & Noltie, 1998). The resulting data from the
computations will be compared to each size of the Chitala ornata specimens in order to
know if there exists a significant difference on the energy conservation in the different sizes
of Chitala ornata. Thus, it shall be subjected to One-way ANOVA test. Differences will be
considered to be significant at p <0.05. All data shall be analyzed using SPPS software
program for statistical analysis (Sarkar, Deepak, Negi, Qureshi & Lakra, 2007).
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24University of Santo Tomas College of Science PAGE
APPENDIX A
Flow Chart
Collection of Chitala
ornataLaboratory set-up
Experiments and
Observation on Prey
Selection and
Consumption
Experiments and
Observations on
Starvation
Data Analysis
25University of Santo Tomas College of Science PAGE
APPENDIX B
Gantt Chart
Activities May Jun Jul Aug Sep Oct Nov Dec Jan Feb
Transportation andhandling of specimens
Laboratory set-up
Acclimation
Experiments andobservations on preyselection andconsumption
Starvation
Analysis of results
Manuscript writing
Thesis defense
26University of Santo Tomas College of Science PAGE
APPENDIX C
Budget Proposal
Items Quantity Price Total Price
Aquaria
≈30 gallons
≈100 gallons
≈200 gallons
1
21
Php 1,000.00
Php 2,500.00Php 4,000.00
Php 1,000.00
Php 5,000.00Php 4,000.00
Tricaine methanesulfonate (MS-222) 1 Php 500.00 Php 500.00
Oxygen pump & filter
Small to medium-sized
Large-sized
21
Php 500.00Php 800.00
Php 1,000.00Php 800.00
Food fish
Live Tilapia (Oreohcromis sp.) of
various sizes
(per month)Php 5,000.00
(≈3 months) Php 15,000.00
LED Moon/ Lunar light 3 Php 1,500.00 Php 4,500.00
Chitala ornata specimens
For experimentation:
Small (30-35 cm)
Medium (50-55 cm)
Large (70-75 cm)
For gut observation:
Small (30-35 cm)
Medium (50-55 cm)
Large (70-75 cm)
555
333
Php 10.00Php 20.00Php 40.00
(per month)Php 10.00Php 20.00Php 40.00
Php 50.00Php 100.00Php 200.00
(≈ 3 months) Php 90.00
Php 180.00Php 360.00
TOTAL Php 32,780.00