reproductive condition of some bat species in mt makiling

7/24/2019 Reproductive Condition of Some Bat Species in Mt Makiling

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Reproductive Condition of Some Bat Species in Mt. Makiling1

Aldaba, Kyra Mari Dominique E.Garcia, Allaine M.

Malsi, Camille Andrea B.

Molina, John Kenneth Q.

Section G-2L

27 May 2015

____________________

1A special problem submitted in partial fulfillment of the requirements in ZOO 148 - Mammalogy laboratory

under Prof. Phillip A. Alviola, 2nd semester, 2014-2015.



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ABSTRACT

The reproductive condition of some bat species in Mt. Makiling was

determined by setting up 16 mistnets in four selected forested areas near CampMalaboo, Mt. Makiling, Laguna last May 2015. The bats captured were identified

as Hipposideros diadema, Ptenochirus jagori, Rhinolophus arcuatus,

Rhinolophus inops and Rhinolophus macrotis. Of the 44 bats examined, 21 were

males and 23 were females. The average range of the testes size of the male bats

is from 8.38mm to 2mm. It was observed that the testes size of male bats are

directly proportional to their gross body size regardless of the species, which also

correlates to their fitness for mating. Twenty out of twenty-three females were

pregnant (10 multiparous and 10 primiparous) while the remaining 3 bats were

nulliparous. The average CRL of the embryo of the pregnant females ranges from

15.07mm to 37mm. It was concluded that bats in Mt. Makiling are reproductivelyactive in May while bats from other locations in the Philippines such as Mt.

Isarog, Camiguin, Palawan, Catanduanes, Leyte, and Mt. Kitanglad were

generally reproductively active from March to September. It was found out that

similar species of bats exhibit differences in gestation periods depending on the

geographic location. Moreover, during these months, female bats were expected

to be most vulnerable to environmental stressors especially anthropological

activities.



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TABLE OF CONTENTS

ABSTRACT i

INTRODUCTION 1

Description of the Study

Objectives of the Study

Significance of the Study

Scope and Limitation of the Study

Time and Place of Study

REVIEW OF RELATED LITERATURE 3

METHODOLOGY 7

RESULTS AND DISCUSSION 10

SUMMARY AND CONCLUSION 20

RECOMMENDATIONS 21

LITERATURE CITED 22

APPENDICES 24



1

INTRODUCTION

Background of the Study

Mammals are considered as a successful group of animals flourishing in and adapting to a

wide range of habitat (Gonzales, Afuang, Alviola, Dans, & de Guia, 1995). In fact, an

exceptional group of mammal modified their forelimbs into fully functional wings that enabled

them to thrive in the air.

The Philippines houses a highly diverse fauna. Currently, there are about 90 recognized

bat species in the Philippines placed under 7 families (Wilson & Reeder, 2005). These include 31

frugivorous and 59 insectivorous bat species and greater parts of these are endemic to the

country. These volant mammals dwell mostly in forests and caves and are mainly nocturnal

animals.

Bats have adapted to a variety of food source and most bat species present in the country

prefer fruit, flowers, and insects among others. It is because of these diets that most of them are

considered pests, especially in a country that rely mostly on crops for income, since they feed

and/or roost in fruit plantations. In some areas, bats are hunted by locals as a meat source, thus

greatly affecting their population negatively. In others, people have learned to live with them

peacefully since bats pollinate fruit trees and regenerate forests. Moreover, they serve as a means

for controlling insect pest population or as a tourist attraction. Some locals even use their dung as

fertilizer (Wund & Myers, Chiroptera, 2005).

Objectives of the Study

This study aimed to determine the reproductive status of the insect and fruit bat species

found in Mt. Makiling.



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Specifically, it aimed to:

1. Identify bat species in the study area and record the reproductive state of each individual;

2. Compare the reproductive biology of each species from the study area;

3. Compare the reproductive biology of each species from the study area with similar

existing studies;

4. Determine the reproductive cycle of each species found in the study area; and

5. Determine the implications of the reproductive biology of bats on their conservation.

Significance of the Study

Chiropterans exhibit an extensive variety on their reproductive biology - one that is

highly variable in addition to differences observed among other mammalian orders. Such

reproductive biology involves reproductive strategies, morphology, and physiology (Heideman

& Powell, 1998). This complexity goes to show that further understanding on bats is needed and

it is therefore important to determine the reproductive status of Philippine bat species and

understand their reproductive biology to help in their conservation.

Scope and Limitation of the Study

The study was limited to the identification of male and female insect bats and fruit bats

found in the study area. Documentation and collection of information on their reproductive state

was done only among species present in the study area that were caught during the netting

nights. The study also included secondary data of the reproductive state of bats found in different

study sites such as Palawan, Camiguin, Mt. Kitanglad, Mt. Isarog, Catanduanes and Leyte based

on similar studies. Moreover, although two netting nights were possible, only the animals

captured on the first netting night were taken into account.



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Time and Place of Study

The study was done in four selected forested areas near Malaboo Campsite situated in

Mt. Makiling National Park, Los Baños, Laguna. Netting nights were done last May 1-2, 2015.

REVIEW OF RELATED LITERATURE

Hipposideros diadema

Hipposideros diadema is commonly known as diadem roundleaf bat. The species is

distributed widely in the country except for Babuyan and Batanes groups of islands (Heaney, et

al. 2006). Males are typically larger than females. According to a study conducted by Rickart, et

al. in 1993 (as cited in Heaney, et al., 2006), the species are commonly found in primary to very

disturbed lowland forest and agricultural areas while the common roosting sites are inside the

caves, tree hollows, and man-made tunnels. Rickart, et al. also asserted that the gestation period

is usually in months of March and May in Luzon, and the females carry a solitary embryo (as

cited in Heaney, et al., 2006). This is supported by a previous study of Heaney in 1999 when two

pregnant females, each with a solitary embryo, were also caught in March 1999 in Mt. Isarog,

Luzon (Heaney, et al., 1999). Furthermore, a study conducted by Esselstyn in 2004 also

supported the idea when 26 pregnant females and 1 carrying a suckling infant – out of 43 female

individuals – were caught in May 15-20, 2000 (Esselstyn, Widmann & Heaney, 2004). Females

also gather in large numbers during the month of March to May wherein each one gives birth to a

single offspring (Nowak, 1999).



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Rhinolophus arcuatus

Rhinolophus arcuatus (Arcuate horseshoe bat) is a member of Family Rhinolophidae. It

occurs in agricultural, montane, mossy, primary, and secondary forests throughout the

Philippines (Rossell-Amball, Tabaranza, & Wright, 2008). It is also found in Sumatra to New

Guinea. This species has two morphotypes: R. arcuatus-s and R. arcuatus-l. The first one is

relatively smaller with a narrower noseleaf, and it usually occurs in lowland caves (Heaney &

Ingle, 1992).

In terms of reproduction, it gives birth only once a year. This is true to all temperate

rhinolophids (Wund & Myers, Rhinolophidae, 2009). This species was found to have gestation

periods in March on Mt. Isarog (Heaney, et al., 1999), in April on Biliran, Leyte, and Maripipi

(Rickart, et al., 1993), and in May on Camiguin (Heaney, et al., 2006) and Palawan (Esselstyn, et

al., 2004).

For the study in Mt. Isarog (Heaney, et al., 1999), 3 males and 2 females were collected

from secondary lowland, disturbed lowland and montane forests on March 1988. One of the

females was primiparous (CRL=6mm) and the other was nulliparous. One male had inguinal

testes and two males had abdominal testes. In Biliran, Leyte, and Maripipi (Rickart, et al., 1993),

all the females collected in April were pregnant (CRL=10-17mm).

In Camiguin, Heaney, et al. (2006) examined 10 individuals of this species, in which 8

males and 2 are females. One female was pregnant (CRL=28mm) and the other female was

lactating. No testicular measurements were given for the males.

In Palawan, Esselstyn, et al. (2004) found out that most of the captured bats in the month

of May are either pregnant or lactating. On the other hand, for those that are captured in the July,

14 bats were lactating and 155 showed absence of reproductive activity.



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Rhinolophus inops

Rhinolophus inops (Philippine forest horseshoe bat) is a member of Family

Rhinolophidae. It is endemic to the Philippines and is most commonly observed in Biliran and

Leyte (Heaney, et al., 1999). There is a variation in this species per geographic area (Heaney, et

al., 2006).

The females of this species have a pair “teat-like appendages” in their abdomen that are

not involved in milk production. Juvenile bats use these to hold on to their mother during flight

(Nowak 1994, as cited in Keller 2013). In addition, females usually give birth to only one young

per year. The gestation period lasts up to 7 weeks and the lactation period lasts up to 8 weeks

(Heaney, et al. 2010, as cited in Keller 2013).

In Mt. Isarog, Heaney, et al. (1999) captured three males only, and they did not provide

testicular measurement for these specimens. In another study in Biliran, Leyte and Maripipi by

Rickart, et al. (1993), the females captured from Biliran and Leyte on March to April 1987 were

pregnant (CRL=8-18mm) with a single embryo. According to Heaney, et al. in 1991 (as cited by

Rickart, et al., 1993), the individuals from Leyte, Biliran and Catanduanes are similar, and those

that are from Negros are relatively smaller. In Kitanglad (Heaney, et al., 2006), pregnancies were

observed in March and September (CRL=20mm) while in Catanduanes (Heaney, et al., 1991), it

was observed on February.

Rhinolopus macrotis

Rhinolopus macrotis (big-eared horseshoe bat) is a member of Family Rhinolophidae. It

occurs from India to Sumatra, including the Philippines. Only a limited number of this species

were captured here in the Philippines. They are most commonly found in caves and man-made

tunnels, where they roost (Heaney, et al., 2006). Very little is known about the reproductive



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condition of this species. The first records of this species from Palawan were captured on May

and July 2000 (Esselstyn, et al., 2004). They were found in disturbed lowland forests. Two

females, both of which are pregnant, were captured in May while eight females were captured in

July, none of which is pregnant or lactating.

Ptenochirus jagori

The species – commonly known as greater musky fruit bat – is endemic to the

Philippines, and occurs throughout the country with the exception of Batanes and Babuyan

Islands, and Palawan Faunal regions (Heaney, et al., 2005, 2006). Males are typically larger than

females. According to Heaney, et al. (2006), the species are commonly found in lowland forest

and secondary forest but unusual at higher elevations and disturbed lower elevation mossy

forests. A study conducted by Heideman and Powell (as cited in Heaney, et al., 2006) revealed

that there are two birthing seasons for the species – in late March or early April and in August –

and females give birth to a solitary offspring. Heideman and Powell also stated that primiparous

females of Ptenochirus jagori can undergo delayed implantation lasting up to 5 months, thus, the

parturition by young females is only once during first year and is concurrent with the second

parturition of adult females. Moreover, a study of Heaney, et al. in Mt. Isarog, Luzon recorded

some pregnant females in the month of May (as cited in Heaney, et al., 2006). Another study of

Heaney, et al. (1999) showed that the testes of adult males are significantly larger than the young

males, 3 x 5 mm to 9 x 12 and 3 x 3 to 6 x 7 mm, respectively.



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METHODOLOGY

Selection of Study Area

The study site, Camp Malaboo, is situated in Mt. Makiling at Luzon Island, Philippines

(Fig. 1). Specifically, Camp Malaboo (14°08’03.09” N, 121°12’27.71” E) is located at Station 15

of Mt. Makiling National Park, Los Baños in the province of Laguna (Fig. 2). The elevation of

the site is estimated to be 650m above sea level. The site in bounded by Los Baños and Calamba

City in the north. Collection sites for volant mammals were chosen near the campsite.

Figure 1. Map of Luzon showing the location of Mt. Makiling.



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Figure 2. Map showing the location of Camp Malaboo in Mt. Makiling.

Collection of Specimens

A total of mist nets – 4 mist nets per collection site – were positioned along the possible

flyways of bats and near feeding trees in the late afternoon. The mist nets were tended

continuously during the peak activity period from 6 o’clock in the evening until 7 o’clock in the

evening, and checked again from 9 o’clock to 10 o’clock in the evening for two nights. The nets

were left open thereafter. The nets were checked again at dawn on the following day. The caught

bats were removed and placed in cloth bags.



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Figure 3. A bat captured in the mist net.

Identification and Processing of the Specimens

On the second day at the campsite, the collected specimens of mammals from the first

netting night were identified based on the Key to the Bats of the Philippine Islands by Ingle and

Heaney (1992). The conditions of male and female reproductive parts were examined by

dissecting specimens in the abdominal area and the data were recorded.

Determination of Reproductive Condition

The reproductive condition of male bats was determined by the measuring the size and

noting the position of the testes. On the other hand, the presence or absence of placental scars,



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reproductive stage, and the condition of mammae were observed for the female bats. Moreover,

for pregnant females, the crown to rump length (CRL) of the embryo was measured.

RESULTS AND DISCUSSION

There were five species of bats from two families (Pteropodidae and Rhinolophidae)

captured through the mistnet laid overnight on May 1, 2015 and identified as the following:

Ptenochirus jagori, Hipposideros diadema, Rhinolophus arcuatus, Rhinolophus inops, and

Rhinolophus macrotis. A total of 48 bats were captured but only 44 were taken into account

because the others were released (Table 1). Among the female bats captured, 20 adult females

were pregnant and 3 were nulliparous. No female bat observed was lactating. Among the males,

12 individuals were adult and 8 were sub-adult. The crown-rump length was measured to

determine the size of the embryo inside a pregnant female. Testes size was measured in the male

individuals caught to distinguish an adult from a sub-adult and to determine the capability of

fertilizing receptive female.

Table 1. Summary of the number of male and female individual bats captured per species.

SPECIES NAME SEX NO. OF INDIVIDUALS

Hipposideros diadema♂ 2

♀ 7

Ptenochirus jagori♂ 2

♀ 8

Rhinolophus arcuatus ♂ 14♀ 3

Rhinolophus inops♂ 2♀ 2

Rhinolophus macrotis♂ 3

♀ 1

TOTAL 44



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SUBORDER MEGACHIROPTERA

Family Pteropodidae – Fruit Bat

Ptenochirus jagori (Peters, 1861), also known as the musky fruit bat, is commonly

found anywhere in the Philippines except in the islands of Batanes, Babuyan and Palawan. It was

recently reported to be capable of delayed implantation like other endemic species such as

Haplonycteris fischeri and Otopteropus cartilagonodus. Male is usually bigger than female.

(Heaney, Tabaranza, Balete, & Rigertas, 2006). Of the ten individuals caught, 8 individuals were

male and 2 were female.

The average CRL of P. jagori observed in Makiling was 37mm (Table 3). The two

pregnant females were both multiparous characterized by their swollen vagina and nipples. The

smallest average CRL was found in Catanduanes (3.5mm). In May, the pregnant bats were more

prominent though in some places like Catanduanes and Mt. Kitanglad, P. jagori could be

observed to gestate also in the months of February, March, July, and August based on previous

studies of mammalian diversity surveys (Table 3). In the study of Heideman and Powell (1998),

facultative post-implantational delay in embryonic development was observed in young females

that would be reproducing for the first time. The delay occurred during gastrulation that could

last up to 5 months in young females and no evidence was found if adult females could delay

embryonic development. The delay would synchronize young pregnant female to the parturition

of the adults. The adult females gave birth twice a year - on late March and early April, and in

August - and each gestation period lasted for four months. (Heideman & Powell, Age-specific

Reproductive Strategies and Delayed Embryonic Development in an Old World Fruit Bat,

Ptenochirus jagori, 1998). It could imply that the pregnant female accounts in other places in the



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Philippines were at the middle of either the first gestation period or the second gestation period

of P. jagori.

Figure 4. A dissected multiparous female P. jagori showing an embryo (CRL=38mm).

The average testes size, of P. jagori observed from the captured male bats in Mt.

Makiling was 8.38mm (Table 4). Among the eight male individuals, five were adults and three

were sub-adults. Most of the adult males have testes size more than 9mm while the sub-adult

males have testes size around 7mm. In another Pteropodidae species like Haplonycteris fischeri,

if a male is born in May or June, its testes volume will still be low but will gradually increase up

to 12 months gaining equivalent testes volume of an adult just in time when the females begin to

be receptive in May and June (Heideman P. D., Delayed development in Fischer's pygmy fruit

bat, Haplonycteris fischeri, in the Philippines, 1989). This may hold true also for P. jagori since

the female has two gestation period every year.



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Figure 5. A dissected male P. jagori with a testes size of 8mm.

Table 2. The parity of the female bats captured per species.

SPECIES NAMENUMBER OF TIMES PREGNANT

Multiparous Primiparous Nulliparous

Ptenochirus jagori 2 0 0

Hipposideros diadema 2 0 0

Rhinolopus arcuatus 5 8 1

Rhinolophus inops 0 1 1

Rhinolophus macrotis 1 1 1



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Table 3. Gestation months and average crown-rump length (CRL) of pregnant some female bats

in selected study areas in the Philippines.

PLACE

of

STUDY

SPECIES NAME

Hipposideros

diadema

Ptenochirus

jagor i

Rhinolophus

arcuatus

Rhinolophus

inops

Rhinolophus

macrotis

Mt. MakilingMay May May May May

(20.50mm) (37mm) (15.08mm) (24mm) (18.50mm)

Mt. Kitanglad -

March, May,

July, August -

March,

September-

- (5.71mm)

Mt. Isarog- May March

-(12mm) (33mm) (3mm) -

PalawanMay

- - -May

- -

Leyte March - April March, April -(15mm) (13.50mm) (13mm)

Catanduanes -February

-February

-(3.5mm) (3mm)

Camiguin -May May

- -(15mm) (14mm)

*References: (Heaney, et al., 1999) (Heaney & Rabor, 1982) (Heaney, et al., 1991) (Heaney, et al., 2006) (Heaney, et al., 2006) (Heideman &

Heaney, 1989) (Rickart, et al., 1993)

Table 4. Average testes size of the captured male bats.

SPECIES NAME AVERAGE TESTES SIZE (mm)

Hipposideros diadema 6.86

Ptenochirus jagori 8.38

Rhinolophus arcuatus 3.50

Rhinolophus inops 4.00

Rhinolophus macrotis 2.00



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SUBORDER MICROCHIROPTERA

Family Rhinolophidae – Horse-shoe nosed Bats

Hipposideros diadema (E. Geoffroy, 1813) is an insectivorous bat that can be found

from Burma to the Solomon Islands and the Philippines with the exception of Batanes and

Babuyan Islands. It is commonly known as the diadem roundleaf bat. Males are a little bigger

than females. The average CRL observed from the two specimens collected in Mt. Makiling was

20.50mm. Both were considered multiparous because of the presence of placental scars and the

swelling of nipples. Pregnancies occur on May in Mt. Makiling and Palawan, and March in

Leyte (Table 3) (Heaney, Tabaranza, Rickart, Balete, & Ingle, 2006). According to Medway,

species of Hipposideros are gregarious, thus H. diadema tends to congregate during March and

April to give birth (Nowak, 1994). In Rickart’s account, species of H. diadema in Luzon will

start the gestation period on March and May (Heaney, Tabaranza, Rickart, Balete, & Ingle,

2006).

Seven male H. diadema - 5 adults and 2 sub-adults - were captured during the first

netting night. Their average testes size was 6.86mm (Table 4). The adult males had more than

6mm testes size while sub-adult males had a testes size of around 5-6mm.



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Figure 6. A dissected male H. diadema with a testes size of 7mm.

Rhinolophus arcuatus (Peters, 1871) is a widespread bat in the Philippines with two

physical differences - a wide ovate-shaped sella and a narrow, rectangular sella (Figure 7)

(Sedlock & Gomez), that have once been suggested by J.E. Hill to be R.arcuatus and R.

anderseni (Heaney, Gonzales, Utzurrum, & Rickart, 1991). Sedlock and Gomez used “narrow”

and “wide” to attach difference while Heaney, et al. (1991) designated “-s” and “-l” to

differentiate the two similar looking bats. It is believed that R. arcuatus was consisted of two or

more species by many researchers (Esselstyn, Widmann, & Heaney, 2004). Based on Table 3, R.

arcuatus captured in Mt. Makiling has an average CRL of 15.08mm, which is the same as in

Camiguin and close in Leyte, but a lot smaller in Mt. Isarog since a small number of individuals

were captured by Heaney, et al. in 1999.



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a) wide sella b) narrow sella

Figure 7. The two morphs of Rhinolophus arcuatus observed from captured specimens.

Among the 14 adult female caught, only one was nulliparous and the rest are pregnant.

The pregnant females were either primiparous (8 individuals) or multiparous (5 individuals)

(Table 2). The pregnancy occurs in May in Makiling and Camiguin while in Palawan, pregnancy

occurs in the months of May, July, August, September; March in Mt. Isarog, and April in Leyte

(Table 3). Lekagul and McNeely in 1977 described that the gestation of period of the species

Rhinolophus takes about 7 weeks producing a young that attains sexual maturity in 2 years

(Nowak, 1994). In temperate regions, rhinolophids reproduce once a year (Wund & Myers,

2009).

Of the three captured male individuals in Mt. Makiling, two were sub-adult and one was

adult with testes size of 1mm and 2mm, and 6mm, respectively. Their average testes size was 3.5

mm (Table 4).

Rhinolophus inops K. Andersen, 1905 (Philippine Forest Horseshoe bat) is an endemic

species of insectivorous bat found in Luzon, Mindanao, Mindoro, and Negros-Panay. It is a

common bat and the males are bigger than females. There were only two specimen caught from

the study - one primiparous female (CRL=24mm) and one nulliparous (Table 2). The occurrence



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of pregnancy increases in the months of May in Makiling, March to Late April in Biliran and

Leyte, March and September in Mt. Kitanglad and February in Catanduanes (Table 3). An

account of a lactating female was recorded in July on Mt. Makiling by Ingle in 1992. (Heaney,

Tabaranza, Rickart, Balete, & Ingle, 2006). Gestation period of R. inops could last for 7 weeks

followed by lactation period of up to 8 weeks (Keller, 2013)

Two males captured on the mistnet but only one was measured because the other male

has testes too small to be measured by a ruler. The measured adult male has a testes size of 4mm.

Figure 8. A female R. inops being dissected to determine if it is pregnant or not.



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Rhinolophus macrotis (Blyth, 1844) - little is known about big-eared horseshoe bat that

is distributed from India to Sumatra and the Philippine. This uncommon bat could be found in

lowland forest and caves. In Palawan, two pregnant female were captured in May and 8 non-

pregnant adult females were captured in July (Esselstyn, Widmann, & Heaney, 2004) while in

Mt. Kitanglad, there were only two preserved specimen available and Heaney, et. al (2006) were

unable to capture a specimen. Last May, two out of three captured female bats in Makiling were

pregnant (one multiparous and one primiparous) with an average CRL of 18.50mm, while the

other one was nulliparous.

Only one male was caught during the netting night. Its testes size was 2mm. Based on the

biometrics obtained, the male bat was a sub-adult not reaching maturity yet. In Himalayas, male

R. macrotis were observed to be sexually active during September (Jnawali, et al., 2011).

Implications of Pregnancy in Female Bats

Since bats are volant mammals, reproduction is energy expensive and is a highly risky

activity (Chaverri & Kunz, 2006). Female bats during pregnancy are more vulnerable to different

stressors most especially to anthropogenic activities like logging, hunting and cave tours

(Sedlock & Gomez). They are also in need to forage double and could go distance to find food.

Fortunately, gestation periods are mostly synchronized to the flowering and fruiting patterns of

plants in the forest as observed by Bronson in 1985 (Chaverri & Kunz, 2006). Since Mt.

Makiling can provide food all-year round being in a tropical country, the species of bats

observed may have synchronized their reproductive activity to the time when the fruit trees of

the mountain is also reproducing.



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Implications of Testes Size in Male Bats

Male bats, like other male mammals, have a pair of testes, epididymis, and vas deferens

with a penis. It was observed by Danmaigoro, et al. (2014) that the male bats gonadal

development was a direct relationship between its reproductive status and body condition index.

They had also reported that the maximum testicular size was associated to the maximal spermatic

activity of adult male bats, which means that the increase of testicular mass and dimension would

play an important role to the spermatogenesis. (Danmaigoro, Onu, Sonfada, Umaru, Hena, &

Mahmuda, 2014).

SUMMARY AND CONCLUSION

The bats captured on May 2015 in Mt. Makiling were identified as Hipposideros

diadema, Ptenochirus jagori, Rhinolophus arcuatus, Rhinolophus inops and Rhinolophus

macrotis.

Among the 44 bats examined, 21 were males and 23 were females. For the males, 10

were subadults and 11 were adults. Their testes size range from 8.38mm to 2mm. For the

females, 20 were pregnant (10 multiparous and 10 primiparous) and 3 were nulliparous. The

CRL of the embryo from pregnant females ranges from 15.07mm to 37mm.

It was concluded that during May, bats in Mt. Makiling are reproductively active. Bats

from other locations in the Philippines such as Mt. Isarog, Camiguin, Palawan, Catanduanes,

Leyte, and Mt. Kitanglad, were observed to be generally reproductively active from March to

September. Consequently, it was found out that similar species of bats exhibit differences in

gestation periods depending on the geographic location. Moreover, during these months, female



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bats were expected to be most vulnerable to environmental stressors especially anthropological

activities.

RECOMMENDATIONS

It is recommended that more netting nights should be done in order to have a normalized

sample set for each species. It is also recommended that further studies regarding the

reproductive condition of the different bat species in the Philippines should be made not only

during the months of gestation but also during the months when bats are expected to be non-

pregnant in order to establish a more informative data to help in the conservation of bats in the

country.



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LITERATURE CITED

Chaverri, G., & Kunz, T. H. (2006). Reproductive biology and postnatal development in the tent-

making bat Artibeus watsoni (Chiroptera:Phyllostomidae). Journal of Zoology, 270, 650-

656.

Danmaigoro, A., Onu, J. E., Sonfada, M. L., Umaru, M. A., Hena, S. A., & Mahmuda, A. (2014).

Gross and Morphometric Anatomy of the Male Reproductive System of Bats (Eidolon

helvum). Veterinary Medicine International , 1-5.

Esselstyn, J. A., Widmann, P., & Heaney, L. R. (2004). The mammals of Palawan Island,

Philippines. Proceedings of the Biological Society of Washington, 3(117), 271-302.

Gonzales, J. C., Afuang, L. E., Alviola, P. I., Dans, A. T., & de Guia, A. P. (1995). A Laboratory

Manual in Wildlife 101: Introduction to Philippine Wildlife. Los Baños, Laguna.

Heaney, L. R., Gonzales, P. C., Utzurrum, R. C., & Rickart, E. A. (1991). The Mammals of

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APPENDICES

Appendix I. Reproductive condition of female bats captured in Mt. Makiling (May 2015).

SPECIES NAMETAG

NUMBER

CRL

(mm)PARITY

UTERINE

HORN WITH

EMBRYO

PLACENTAL

SCAR

Hipposideros diadema JDVA 0846 21 multiparous left present

Hipposideros diadema JDVA 0851 20 multiparous left present

Ptenochirus jagori JDVA 0810 38 multiparous* left present

Ptenochirus jagori JDVA 0817 36 multiparous right present

Rhinolophus arcuatus JDVA 0835 19 multiparous left present




Rhinolophus arcuatus JDVA 0844 12 primiparous left absent







Rhinolophus arcuatus JDVA 0822 n/a nulliparous n/a absent

Rhinolophus arcuatus JDVA 0838 15 multiparous right present

Rhinolophus arcuatus JDVA 0819 13 primiparous right absent

Rhinolophus inops JDVA 0848 24 primiparous left absent

Rhinolophus inops JDVA 0808 n/a nulliparous n/a absent

Rhinolophus macrotis JDVA 0849 20 primiparous left absent

Rhinolophus macrotis JDVA 0855 n/a nulliparous n/a absent

Rhinolophus macrotis JDVA 0847 17 multiparous right present

*with swollen vagina and nipples



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Appendix II. Reproductive condition of male bats captured in Mt. Makiling (May 2015).

SPECIES NAME TAG NUMBER TESTES LENGTH (mm)

Hipposideros diadema JDVA 0825 7







Ptenochirus jagori JDVA 0812 8








Rhinolophus arcuatus JDVA 0828 2



Rhinolophus inops JDVA 0814 n/a*

Rhinolophus inops JDVA 0820 4

Rhinolophus macrotis JDVA 0850 2

*too small to measure

reproductive condition of some bat species in mt makiling

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