Cave bats
of the central west coast and southern section of the Northwest Panay
Peninsula, Panay Island, the Philippines
Antony Mould
Philippine Spotted Deer
Conservation Foundation, Villa Tinigbas, Barangay Tinigbas, Libertad
Municipality, Antique Province, Panay Island, Philippines 5710
Email: antonymould@hotmail.com
Date
of publication (online): 26 September 2012
Date of publication (print):
26 September 2012
ISSN 0974-7907 (online) |
0974-7893 (print)
Editor: Dave
Waldien
Manuscript details:
Ms # o3104
Received 19 February 2012
Final received 03 June 2012
Finally accepted 26 August
2012
Citation: Mould,
A. (2012). Cave bats of the central west coast and southern section of the
Northwest Panay Peninsula, Panay Island, thePhilippines. Journal of Threatened Taxa 4(11): 2993–3028.
Copyright: © Antony
Mould 2012. Creative Commons Attribution 3.0 Unported
License. JoTT allows unrestricted use of this article in any medium for
non-profit purposes, reproduction and distribution by providing adequate credit
to the authors and the source of publication.
Author Details: Antony
Mould works within the environmental sector in England, and is
actively involved in promoting bat conservation as a member of the
Cambridgeshire Bat Group. He has participated in overseas research projects on
seabirds in Alaska, and bats in Tasmania, and he undertook the present research
whilst volunteering for the Philippine Spotted Deer Conservation Foundation.
Acknowledgements:I would like to thank the following people for their help and assistance during
the fieldwork undertaken as part of this project: Raphael Mateo, Reggie Mateo,
Claire Celestino, Herbert Magluyan, Raymond Magluyan, Nilo, Bo Bong, Woody
Montana, Lindsay, Donna Rana (DENR), Aida Laggie, Norberto P. Raymundo Jr.
(Mayor of Libertad), Faith Francisco (Mayor of Barbaza), Christian and Remy,
and Julie Danby. Special thanks to Renee Galang (under whose Gratuitous Permit
the current study has been undertaken) for allowing me to participate on the
PSDCF project and encouraging my bat research interests by locating caves and
organising the survey trips documented in this paper. I would also like to
thank the following people for their help and assistance with the preparation
of this paper: Nina Ingle, Lawrence Heaney, Jodi Sedlock and David Waldien.
Abstract: Bats (order Chiroptera) form a
large proportion of the species-rich mammalian fauna of the Philippines, and
while the threats posed to these animals are well documented, for many species
there is currently insufficient data to enable even a basic assessment of their
conservation status. This is true
for Panay Island, located in the Western Visayas region of the archipelago,
where the need for surveying remaining suitable bat habitat has been identified
as a priority. Between 5 April and
9 May 2011 a survey of 21 caves was undertaken on Panay, along the central
section of the west coast of the island and within the southern section of the
Northwest Panay Peninsula. Survey
methods included visual observations, emergence counts and the recording of
echolocation calls. Of the caves
surveyed, 19 were found to support bats or show signs of their use, and at
least 12 different species were observed. Three large maternity colonies of the Common Rousette Rousettus amplexicaudatus and two of the Dusky Roundleaf Bat Hipposideros ater were noted as having particular significance in terms of their
conservation value for local populations. Potential maternity colonies of Asian Lesser False Vampire Megaderma spasma, Black-bearded Tomb Bat Taphozous melanopogon and Diadem Roundleaf Bat Hipposideros diadema were also observed but not confirmed. M. spasma was the most frequently encountered species, occurring in small
numbers at five different caves. Other species/genera encountered in small numbers were the Arcuate Horseshoe
Bat Rhinolophus
arcuatus, Common Short-nosed Fruit Bat Cynopterus brachyotis, Philippine Sheath-tailed Bat Emballonura alecto, Yellow-faced Horseshoe Bat Rhinolophus virgo, Bent-wing (Miniopterus) and Myotis bat species, and at least one other Horseshoe (Rhinolophus) bat species. Ten of
the caves were confirmed to support multiple bat species. An indication of current threats and
recommendations for further survey and management priorities are provided.
Keywords: Bat, cave, Hipposideros
ater, Panay, Philippines, Rousettus
amplexicaudatus
Tagalog Abstract (National language of the Philippines). Abstraksyion: Ang mga paniki (order Chiroptera) ay maraming klase at malaking
parte na mamal na hayop sa Pilipinas. Na dukomenta na ang mga pusible at delekadong sitwasyon sa mga hayop na
ito, pero sa karamihan sa kanila kulang parin ang mga besik na data para
malaman natin ang mga konserbasyon status nila. Ito ang katutuhanan sa isla ng Panay sa kanluran ng visaya sa arkipelago. Dito
ang naging prioridad na ma survey and mga natitirang
tirahan ng mga paniki. Nuong a singko ng Abril hangang a nuebe ng Mayo 2011
sinurvey and benti uno na kweba sa Panay na nasa
central kanluran sa dalampasigan hangang sa timog ng ilalim na seksyon ng
hilagang kanluran ng Panay peninsula. Ang mga ginamit napang survey ay pag tingin, pag bilang bago mag dilim, at rekording ng mga ingay
at tawag nila. Sa mga kweba na sinurvey, disinuebe ang
may laman na paniki o may sinyales na may paniki, at dose na klase na paniki
ang na obserba. Tatlong may mga anak na kolony ng Rousettus amplexicaudatus at dalawang Hipposideros ater ang na obserba. Ito ay may
importanteng signipikanse sa konserbasyon ng local na
papulasyon ng mga klaseng paniking ito. Baka meron ding may manga anak na kolony ng Megaderma spasma, Taphozous melanopogon at Hipposideros diadema pero hindi ito na konpirma. M. spasma ay nakita sa limang kweba pero maliit lang ang mga papulasyon
nito. Ang ibang mga species/genera na nakita pero
konti lang sila ay ang Rhinolophus arcuatus, Cynopterus brachyotis, Emballonura alecto, Rhinolophus virgo, Miniopterus at Myotis species. At meron ding Rhinolophus species. Sampong mga kweba ang
may maraming species na paniki. Indikasyon ng mga
kasalukuyang pagbabanta at rekomendasyon para sasusunod na survey at pamamahala na prioridad ay sinama.
Abbreviations: BCI - Bat Conservation
International; CF - Constant Frequency; DENR - Department of Environment and
Natural Resources; IUCN - International Union for the Conservation of Nature;
FM - Frequency Modulation; PESCP - Philippine Endemic Species Conservation
Project; PSDCF - Philippine Spotted Deer Conservation Foundation.
For
figures, images, tables -- click here
Introduction
The
mammalian fauna of the Philippines is considered to be one of the most
species-rich in the world, with a high level of endemism; unfortunately, it is
also one of the most extensively endangered (Heaney 1993; Heaney et al.
1998). A large proportion of this
fauna comprises bats (order Chiroptera) with currently 79 described species
from seven families (Heaney et al. 2010). New species are still being discovered, such as the Mindoro stripe-faced
Fruit Bat Styloctenium mindorensis (Esselstyn 2007), and uncertainties
regarding the status of a number of currently recognised species and subspecies
within genera including Cynopterus, Hipposideros and Rhinolophussuggest that new species are also likely to be described in the future (e.g.,
Campbell et al. 2004; Heaney et al. 2010).
Over 40
species of Philippine bats roost in caves (Heaney et al. 2010). The threats to these species are well
known, ranging from direct impacts (destruction of caves through development
pressure, disturbance of roost sites through insensitive tourism activities,
harvesting of bats as a local source of food and collection of guano) to
additional indirect pressures such as loss of foraging habitat from ongoing
deforestation (e.g., Mickleburgh et al. 1992; Mendoza & Mallari 1997;
Hutson et al. 2001). Despite these
known and increasing threats, for many species there is currently insufficient
data (location of caves and the species they support, population estimates and
trends, local threats) to enable even a basic assessment of their conservation
status (Oliver & Heaney 1996; Heaney & Regalado 1998; O’Malley et al.
2006; Turner et al. 2006; Heaney et al. 2010). Islands and caves in particular have
been identified as two crucial issues where co-ordinated actions are required
to ensure the survival of bats, but which currently receive insufficient
attention from many conservationists (Mickleburgh et al. 2002).
Within the
Philippines, the mammalian fauna of the Greater Negros-Panay Faunal Region is
the most threatened (Heaney 1993; Heaney & Regalado 1998). As of 2009, 464 caves were known from
the faunal region, representing 22% of all caves recorded within the
Philippines (DENR-PAWB 2009). Panay
Island lies in the west of the region and covers an area of 12,300km2(see Fig. 1). Historically, Panay
was covered in tropical rainforest, and while the island has the largest
remaining forested areas in the region, only 8% of the original forest cover
remains (Pedregosa 2005). The
majority of the remaining forest is now included within protected areas in some
sections of the Central Panay Mountain Range and the Northwest Panay Peninsula
Natural Park, and the Haribon Foundation is actively working on the process of
protecting the whole of the Central Panay Mountain Range (R. Galang pers. comm.
20 March 2012). However, despite
ongoing efforts at a legislation and policy level, there is insufficient
government funding to enable non-governmental organisations and academic
agencies to achieve effective conservation of protected areas or the endangered
habitats and species they support on the ground (Pedregosa 2005; Subade &
Jugado 2010). Records of caves on
the island are limited, and focused within the provinces of Aklan, Capiz,
Iloilo and the central-eastern area of Antique (DENR-PAWB 2009).
In terms of
mammal diversity, 29 species have been documented on the island, of which 20
are bats (Heaney et al. 2000). In
comparison 49 species of mammals have been recorded on Negros (an island of
similar size and biogeographic history) suggesting that the fauna of Panay is
yet to be fully documented (Heaney at al. 2000). Research activity on the fauna and flora
of the island has recently been increasing thanks to the efforts of organisations
such as the now-lapsed Philippine Endemic Species Conservation Project (PESCP)
and the Philippine Spotted Deer Conservation Foundation (PSDCF) (e.g., Curio et
al. 1996; Klop et al. 1998; Gaulke & Curio 2001; Galang & Madulid
2006). While a limited amount of
work has been undertaken into the bats of Panay (e.g., Reiter & Curio 2001;
Reiter et al. 2006), little has focused on the distribution and status of
species within the island. There is
thus a clear need to survey suitable remaining habitats (forests and caves) to
identify significant bat populations and assess their conservation importance
(O’Malley et al. 2006). Such
information should then be used to inform the conservation action that is
required (Heaney et al. 2000).
During 2011,
PSDCF initiated a programme of surveys on bat populations within local caves of
western Panay to begin to address the existing lack of baseline information for
the island. Specifically, the aims
of this study were to determine the species of bats observed within caves,
estimate the numbers present, and record ecological information such as
roosting preferences, indications of reproduction, and echolocation calls. This information could then be used to
provide baseline data to the DENR for their formal survey and assessment work
under the National Caves and Cave Resources Management and Protection Act of
2001, provide an assessment of current risks and provide recommendations for
further survey work and management requirements where necessary.
Materials and
Methods
Study Area
Survey
effort was focused in the province of Antique, and in particular the
municipality of Libertad around the southern coast of the Northwest Panay
Peninsula, where the PSDCF has its base of operations. However, specific expeditions were also
undertaken to the northern section of the Central Panay Mountain Range in
Ibajay, Aklan, as well as the municipalities of Culasi (including Malalison
Island) and Barbaza on the west coast of the island. Locations of the survey
areas are shown in Fig. 2.
Cave Surveys
Between 5
April and 9 May 2011 a total of 21 caves were visited. Caves were identified through
discussions with various sources (local barangay officials and guides,
landowners, municipality environment officers and mayors, and DENR staff), or
had already been located through previous PSDCF expeditions.
Once
identified, caves were visited with the help of local guides and explored as
far as was practical, in survey teams of between two to seven people. In Barbaza the local guides were aware
of several additional caves in the area, but were unable to locate them during
the survey trip. Cave location
co-ordinates were recorded using a Garmin GPSMAP 76CSx receiver (serial no.
76405972), and plotted using Mapsource Version 4.0 (Garmin Ltd). For each cave an initial, rapid
assessment was undertaken, taking up to an hour to complete depending on the
size of the cave. During the
assessment rough descriptions of cave features and approximate dimensions were
written down and sketched, and the presence of any notable fauna was
recorded. In addition, signs of
disturbance (such as graffiti and treasure-hunting) were recorded, along with
any anecdotal information from guides, landowners or local officials (mayors,
municipal environment officers, DENR staff) on current activities within the
caves (such as tourism and bat harvesting).
All survey
and specimen collection activities were undertaken under Gratuitous Permit
R6-2011-06. Where bats were
encountered, photographs and visual observations (such as roosting location and
presence of juveniles) were made, and species were subsequently identified
using Ingle & Heaney (1992) and Heaney et al. (2010). When dead bats were found, these were
collected and relevant measurements (as described in Ingle & Heaney 1992)
were taken using callipers to further aid identification. Where feasible, estimates of bat numbers
were made by visual observation, or where large colonies of bats were present,
numbers were estimated by undertaking subsequent evening emergence surveys
outside cave entrances. The method
followed that described by Churchill (2008) - at least two observers were
positioned at suitable vantage points outside cave entrances prior to dusk, and
the number of bats flying out were tallied until emergence activity ceased. Two methods of counting were employed,
depending on the visual circumstances at the cave: (i) full counts of all bats
seen emerging, (ii) bat emergence rates were established using sample
one-minute emergence counts, and then multiplied by the total colony emergence
time to provide an overall estimate of numbers. A Batbox Duet frequency division bat
detector was used to help confirm species identification of large fruit bat
colonies during cave assessments and emergence counts - Rousettus is the
only genus of fruit bat that echolocates (Dumont 2003), and in the Philippines
the genus is represented by a single species, the Common Rousette Rousettus
amplexicaudatus (Heaney et al. 2010). Whilst R. amplexicaudatus could therefore be confirmed within
large colonies through the detection of echolocation calls, it was not possible
to determine whether other fruit bat species were also present - for example, R.
amplexicaudatus is often found roosting in association with the Common
Nectar Bat Eonycteris spelaea (Payne & Francis 2005).
Echolocation
recordings were obtained from free-flying individuals within the caves to aid
with the identification of species that were difficult to confirm visually,
particularly horseshoe bats (Rhinolophus sp.). Recordings were made using a Batbox Duet
frequency division bat detector attached to an iRiver T20 MP3 recording device.
The resulting MP3 files were converted to WAV files using JetAudio 6.1
(JetAudio Inc) to enable an analysis of sonograms using BatSound Standard - Sound
Analysis Version 3.31 (Pettersson Elektronik AB). Analysis focused on
call type (Constant Frequency (CF), Frequency Modulation (FM)) and call
frequency (KHz), where calls are defined as discreet echolocation pulses
separated by inter-pulse intervals within a call sequence. There is currently no reference library
for Panay bat echolocation calls; however, comparison was made with calls from
previous studies of bat echolocation calls recorded elsewhere in the Philippines,
in central Luzon (Sedlock 2001).
Where bats
were not encountered, but other evidence of current or former occupancy (piles
of guano, staining on walls) was present, this was noted down. Caves showing no signs of current or
former occupancy were also recorded.
Results
Of the 21
caves that were visited, 19 were either found to support bats or evidence of
their occupancy was observed. A
total of nine species were positively identified, and at least another three
were observed but only identified to genus level. Five large maternity roosts were
confirmed, three of the Common Rousette Rousettus amplexicaudatus and
two of the Dusky Roundleaf Bat Hipposideros ater. In addition, potential maternity
colonies of Asian Lesser False Vampire Megaderma spasma, Black-bearded
Tomb Bat Taphozous melanopogon and Diadem Roundleaf Bat Hipposideros
diadema were observed but not confirmed. M. spasmawas the most frequently encountered species, occurring in small numbers at five
different caves. Other
species/genera encountered in small numbers were the Arcuate Horseshoe Bat Rhinolophus
arcuatus, Common Short-nosed Fruit Bat Cynopterus brachyotis,
Philippine Sheath-tailed Bat Emballonura alecto, Yellow-faced Horseshoe
Bat Rhinolophus virgo, Bent-wing (Miniopterus) and Myotisbat species, and at least one other horseshoe (Rhinolophus) bat
species. Ten of the caves were
confirmed to support multiple bat species. A range of human activities were observed at a
number of caves.
Cave
locations are shown in Fig. 2. Summary information for each cave is provided in Table 1, with the bat
observations further summarised by species in Table 2. Detailed cave descriptions and
individual species accounts are provided below, with cave illustrations and
photographs provided in Appendices 1–18.
Cave Descriptions
In the following
accounts, the physical structure and setting of each cave is described, along
with any observations or reports of current or historic human activities. This information is summarised in Table
1. Names in brackets refer to local
municipalities and provinces. ‘Barangay’ refers to an administrative division
within a municipality (effectively a village), and ‘sitio’ refers to a further
sub-division that is sometimes recognised (particularly in rural areas or for
discreet settlements located some distance from a barangay centre).
Cave 1 (Buruanga, Aklan) (Appendix 1): A small, remote limestone cave on a
steep forested slope along the uninhabited western coast of the Northwest Panay
Peninsula. There are two entrances
in the main upper cavern, opposite each other, producing a relatively well-lit
interior. In the centre of the cavern is a pillar, beyond which the floor
slopes down steeply into two short chambers, one of which is blind-ending,
the other opening out into a lower level entrance. The main cavern is approx 5m across and
12m deep, with a ceiling height of approx 20m from the floor of the lower
chambers. There appears to be
little disturbance, although the cave is known by local
fishermen who frequent the nearby coastline, and youths coming from the nearest
barangay (graffiti is present inside the cave).
Caves 2 and 3 (Libertad, Antique) (Appendix 2 & 3): Small limestone caves (approx 4m high
and 8m deep) in close proximity, each consisting of a single entrance and
cavern. They are located on the
edge of mixed plantation and secondary forest, close to the local sitio, and
are frequently visited. Cave 3
showed obvious signs of recent disturbance, with the bottom of the cavern
having been repeatedly dug up by a treasure hunter.
Cave 4 (Libertad, Antique) (Appendix 4): A large, remote limestone cave located
in the interior of the peninsula, within mixed plantation and secondary
forest. There is a large 7m
vertical slit in a limestone face, leading into the main, approx 15m high cavern. Two side
branches lead off from this—one relatively short (approx 15m) to the
right, and a longer one to the left (not fully explored). The bottom of the main cavern narrows
into a small chamber and at the base of this there is running water (not
explored). The cave is known to the
nearby sitio and has been harvested for fruit bats historically, although this
has ceased for the last two years.
Cave 5 (Libertad, Antique) (Appendix 5): Located close to Cave 4, this is a
low-ceilinged, shallow-sloping limestone tunnel (approx 50m long), open at both
ends. The combination of
stalactites/stalagmites and small dimensions makes passage through the tunnel
quite difficult in several places. The
tunnel has only recently been discovered by the local sitio.
Cave 6 (Libertad, Antique) (Appendix 6): A large complex limestone cave system
located in the interior of the peninsula, within secondary forest. There is a sink holesloping down to a large cave entrance and a steeply sloping, 30m long outer
chamber. At the back right corner
the ceiling slopes down and leads into a very low narrow passage full of
stalactites/stalagmites which has to be crawled
through. Part of this passage also
has a shallow water pool in it. The
passage comes out as a tight opening into a larger, perpendicular tunnel with a
stream running along it. Turning
right, this passage runs for approx 30m until it comes to a dead end, although
there are several small blind-ending chambers/tunnels leading off. Turning left the tunnel runs for at
least 30m until the ceiling becomes very low and further crawling is required
(this direction wasn’t explored any further). Coming off this section of tunnel is a
passage on the right which rejoins the main tunnel, followed by a longer
passage, again on the right, which slopes up and runs for approx 30m. Following this, it then opens up into a
wider passage on the left, which in turn opens out into three large caverns
(each between 15–20m deep by 15m high). The third cavern was not fully explored,
and this could lead onto further caverns/tunnels. The local barangay are aware of the
cave, but it is difficult to get into and appears to have been left
undisturbed.
Cave 7 (Libertad, Antique) (Appendix 7): A well-known cave located in a river
valley within secondary forest, accessed from the nearby barangay via an easy
walk along a well-used river trail. A short tunnel entrance leads into a large single cavern (approx. 25m
high) with one upward-sloping side chamber near the entrance and a large cavity
high up in the right hand side wall and roof at the
back. There is lots of disturbance
from frequent visits by local people and occasional foreign tourists. For example, the municipal environment
officer mentioned a recent visit by around 800 girl guides, all in the main
cavern at the same time. Apparently, coconut leaves are frequently lit inside the cave to
illuminate the ceiling of the cavern for visitors.
Cave 8 (Libertad, Antique) (Appendix 8): A confined limestone tunnel with a
concealed entrance in a vegetated slope along the same river valley as Cave
7. Approximately 50m into the
tunnel, there is a water pool spanning its entire width. Passage beyond this point proved
difficult because the ceiling gets very low and the floor of the pool is soft
and muddy (up to shin deep), so the majority of the tunnel was unexplored. According to our guides the tunnel
eventually comes out at another entrance in a neighbouring barangay, and local
children are known to explore and play throughout it.
Cave 9 (Libertad, Antique) (Appendix 9): Another well-known, easily accessed
limestone cave consisting of three low-ceilinged caverns, located within the
same river valley as Caves 7 and 8. The outer cavern (approx. 20m wide x 10m
long x 5m high) is open-mouthed and very light. It is used by the local barangay as a
regular venue for mat-weaving activities and therefore receives regular heavy
disturbance. A small constriction
at the back of the outer chamber leads into a second slightly larger, dark
cavern, which in turn leads into a narrower 15m long chamber. These adjoining caverns are less
disturbed.
Caves 10 –13 (Libertad, Antique) (Appendix
10–11): Limestone
caves within a private coastal property originally planned for a hotel
development, but now kept as a garden with minimal management. Cave 10 (Appendix 10) is a coastal
cavern with a wide open mouth, and is only accessible
by land at low tide. There is an
adjacent smaller coastal cavern (Cave 11) that is accessible at all tides, with
no sign of bats recorded. Cave 12
(Appendix 11) is within the garden itself and has a small, partially collapsed
entrance with a 10m vertical drop leading into small, sloped cavern, approx 7m
deep. There is another smaller
vertical cave within the garden (Cave 13), again with no sign of bats
recorded. There is currently
little/no disturbance to any of the caves.
Cave 14 (Libertad, Antique) (Appendix 12): A small, shallow limestone cave (<5m
deep) on the edge of a pool and waterfalls forming part of a river. The base of the cave is filled with
water to a depth of approx 0.5m. The cave is a 2hr walk from the nearest barangay, along a reasonably
difficult route upstream into hilly primary and secondary forest. However, the river, waterfalls and pools
are a local tourist destination (although probably not often visited) and are
well used by the locals for fishing and recreation; groups of youths and
children were seen fishing and playing in the waters, and it is likely that
children play within the cave.
Cave 15 (Libertad, Antique) (Appendix 13): A large, steep (vertical in several
places) tunnel-like limestone cave with intact stalactite formations. The explored section of cave was at
least 75m long, and comprised three distinct chambers. This is a remote cave located on private
property in the hilly interior of the peninsula, within mixed plantation and
secondary forest. It is difficult
to find and get into and currently appears to receive little/no disturbance.
Cave 16 (Ibajay, Aklan) (Appendix 14): A very remote limestone cave system
accessed via a 3–5hr easy walk up river to Yawan barangay, followed by a
5–7hr difficult river/mountain trek into the primary forests of the
Central Panay Mountain Range. There
is a crater (approx. 15m long and deep), leading on one side into
(16a)—an open cavern (with a ceiling height of approx. 15m), at the far
end of which is a big opening in the ceiling (effectively the cavern is an
extension of the crater, with a land bridge over the top). On the other side of the crater there is
(16b)—a large cave entrance (10m across by 5m high) leading into two big
closed chambers of approx. 30m length, one sloping upwards, theother downwards. A short distance
from the crater complex there is (16c)—another small cave entrance (2m
across by 3m high) leading into a separate, smaller cavern (this was not
explored and it is not known whether it connects with the main cave
system). Intact stalactites and
stalagmites are present throughout the system. Due to its remote location there is
little disturbance to the cave system. However, bat-harvesting does occur here, and
according to the Yawan locals, despite the difficult journey a hunter can take
a 30kg sack of bats in one trip. The locals also believe that recently there has been an increase in
harvesting, due to hunters from barangays on the other side of the mountain
range discovering the cave.
Cave 17 (Sebaste, Antique) (Appendix 15): A large, single, well-lit limestone
cavern (approx 15m deep by 15m high) with two entrances, one at ground level
and one high up in the ceiling. The
cave is located in secondary forest/scrub on the edge of rice fields. Nearby is a locally well-known camp of
flying foxes (these have previously been identified as Pteropus hypomelanus– R. Galang pers. comm. 12 April 2011) which is
visible from the main provincial road into Culasi. The cave appears to be known locally and
is probably used by youths (graffiti is present).
Cave 18 (Appendix 16) and 19 (Culasi, Antique): Vertical fissures in the south and north
cliff faces of a small rocky island to the west of Malalison Island. Cave 18 is approx 5m deep by 20m high,
and towards the back a beach rises from the sea,
leading to a slightly deeper, 2m high recess at the base of the back wall. In the roof of this recess there are
lots of cracks and crevices. Cave
19 is a generally smaller fissure than Cave 18, but at the back/bottom of it
there is a hole in the cliff leading into a small sea cavern (approx. 5m wide x
5m deep x 3m high). These sites are
not accessible by land and as a result receive little/no disturbance.
Cave 20 (Barbaza, Antique) (Appendix 17): A small entrance hole in a
well-vegetated, rocky limestone hill, with a short 5m vertical drop leading
down into a sloping cave consisting of seven inter-connected caverns. The largest cavern was approx 8m across
by 5m deep by 4m high. Although the
general area is limestone, the inside of the cave has a very smooth floor. The cave is known by the local barangay
and receives occasional visits from youths (graffiti is present on the walls). However, our guides had difficulty
finding the cave and said they weren’t aware that anyone had visited it during
the last two years.
Cave 21 (Barbaza, Antique) (Appendix 18): A 10m long tunnel in a well-vegetated,
rocky limestone hill, leading into a more open, 15m high-ceilinged cavern at
the back. There were several
smaller chambers leading off from this cavern, but these were high up and not
easily accessible. The cave is known by the local barangay and more frequently visited
than nearby Cave 20 (there is more extensive graffiti present on the
walls). However, our guides still
had difficulty finding the cave.
Species Accounts
The
following detailed species accounts are summarised by cave in Table 1, and by
species in Table 2. Echolocation
calls were recorded in four caves to further aid identification of the bat
species present - the results are summarised in Table 3 and discussed further
in the relevant species accounts, with example sonograms provided in Figs.
3–6.
Pteropodidae
Rousettus
amplexicaudatus: Three
large maternity roosts were observed in Caves 4, 7 and 16. At the entrance to Cave 4 there were
obvious fruit bat smell and sounds, and as we entered the cave, large numbers
of bats were seen in the main cavern. Smaller individuals (juveniles) were observed, and one photo taken
inside the cave clearly shows an adult in flight carrying a well-developed
young. The bats were easily
disturbed (presumably due to historic harvesting) and the majority flew into
the longer side branch on the left. An emergence survey provided a population estimate of 6,500 (actual
count) - 8,000 (based on emergence rates) individuals. At Cave 7 large numbers of this species
were observed roosting in the cavity high up in the right hand side wall and roof at the back of the main cavern. A scattering of
individuals were also observed high up on the ceiling of the main cavern
itself, although these could have been a different fruit bat species. An emergence survey at the cave provided
a population estimate of 3,400 individuals (actual count). At Cave 16 a mass of bats was observed
on the ceiling of the land bridge (16a), with lots of flight activity in the
twilight zone beneath. There was a
layer of guano in this area, at least ankle deep. In the cave opposite (16b) huge numbers
of bats were again present, on the ceiling of the upper cavern, with
corresponding amounts of guano. Bats were also observed in the lower cavern,
but in far fewer numbers. At the
nearby smaller cave (16c) there was lots of noise coming from inside and
numerous bats were seen flying past the entrance, including adult females with
young attached. A partial emergence
survey of one side of the land bridge and the main cave entrance provided a
population estimate of 198,000 individuals (based on emergence rates). Observer
locations and views during this emergence survey are shown in Appendix 14.
Cynopterus
brachyotis: Small
numbers of individuals were observed in Caves 9, 15 and 17. At Cave 9 a single bat was recorded
hanging from the ceiling in the dark zone. At Cave 15 two bats were seen in a roof crevice next to a stalactite in
the twilight zone. At Cave 17 five
bats were disturbed from the ceiling in the twilight zone near the cave
entrance, which flew around and eventually settled part way up the back wall of
the cave.
Fruit Bat sp.
At Cave 7
approximately five fruit bats were observed high above, scattered across the
ceiling of the main cavern, separate from the large roost of R.
amplexicaudatus. It was not
possible to confirm whether these were also R. amplexicaudatus or a
different fruit bat species.
Emballonuridae
Taphozous
melanopogon: A colony of approximately 50 bats was
observed in the light zone, hanging free from the walls of a south-facing sea
cliff fissure (Cave 18). They were
easily disturbed - several flew out into the open, while the rest flew into the
recess at the back of the fissure and crawled up into cracks and crevices in
the recess ceiling. Three bats were
subsequently observed hanging free from the walls of another fissure on a
north-facing cliff (Cave 19), and presumably these were bats that had been
disturbed from Cave 18.
Emballonuraalecto:
Small numbers of individuals were observed in Caves 1, 10 and 15. At Cave 1 three bats were observed
hanging free on the wall at the back of the upper cavern in the twilight
zone. They were easily disturbed,
continually flying around, although they didn’t leave the cave. At Cave 10 five bats were seen hanging
free on a wall in the twilight zone near the cave entrance, subsequently
crawling backwards into crevices upon disturbance. At Cave 15 two bats were seen hanging
free on a wall in the twilight zone of the outermost chamber.
Megadermatidae
Megaderma
spasma: With records
from five caves (Caves 5, 9, 10, 12 and 20), this was the most frequently
encountered species. A small colony of 15 bats was observed in Cave 12, with
animals hanging individually and in small clusters from the ceiling at the back
of the cavern in the dark zone. A
further two bats were observed on the ceiling in the dark zone of the nearby
Cave 10. At Cave 9 two individuals
were seen hanging together from the ceiling of the second cavern, and at Cave
20 a colony of eight bats was observed in the deepest cavern of the
system. At Cave 5 a partially decomposed
corpse was found on the floor of the tunnel (skull measurements: condylocanine
length = 22.5mm, maxillary toothrow = 9mm; body measurements: hind foot = 8mm,
forearm = 59mm).
Hipposideridae
Hipposideros
ater: Two large
maternity roosts were observed in Caves 6 and 20. At Cave 6 a large colony of bats,
potentially numbering in the thousands, was observed in the three caverns
located furthest into the cave system. Individuals were seen hanging free from the ceilings and walls, and a
mother with a blind, naked pup was observed. There was a significant quantity of
guano (covering the ground of all the caverns, ankle deep in places), and a
noticeable smell. The bats were
easily disturbed, and subsequently encountered flying along the entire length of
the cave system, all the way to the outer chamber. The colony comprised at least three
species (Rhinolophus arcuatus and a microbat sp. were also observed),
and only a rough estimate of numbers could be made on the single visit
undertaken as part of the present study. Nevertheless, H. ater was the predominant species observed, and
an impression of the quantity of bats encountered, together with the extent of
guano and the fact that the large maternity roost caverns were not fully
explored suggests that numbers in the cave system could be in the
thousands. At Cave 20 individual
bats were seen flying around and hanging on the walls of the outer caverns, and
the main roost area was located in the fourth cavern, with approximately 200
bats seen hanging from the ceiling and flying around. A very young juvenile (naked and blind,
with just a hint of fur coming through) was observed hanging from the ceiling,
confirming that this is a maternity site. The bats appeared very sensitive to disturbance.
Hipposideros
diadema: At least 35
bats, in groups of five, 10 and 20, were observed hanging free on walls in the
dark zone of the explored chambers of Cave 15. Echolocation calls were detected further
beyond, indicating that more bats were present, but deeper exploration into the
cave was not made. Given the size
of the cave, the lack of disturbance and the intensity of echolocation calls
recorded, there is potential for a large colony of bats to be present. This species was recorded using constant
frequency/frequency modulation (CF/FM) calls with a mean CF component of 69.4
kHz. This is slightly higher than
the mean call frequency of 67 kHz recorded for this species elsewhere in the
Philippines within central Luzon (Sedlock 2001). However there is good overlap
between the ranges of call frequencies recorded from the two areas.
Rhinolophidae
Rhinolophus
arcuatus: Individual
horseshoe bats were noted in the first large cavern of Cave 6, including a
recently deceased animal hanging free from a wall. The specimen was collected and
subsequently identified as R. arcuatus (body measurements: total length
= 68mm, tail = 17mm, hind foot = 11mm, ear = 18mm, forearm = 47mm, weight =
9g).
Rhinolophusvirgo:
At Cave 1 a single bat was seen hanging free near the passage down to the lower
chamber. Upon discovery it flew
into the adjacent blind chamber, and then back again, before exiting the cave
via the lower entrance.
Rhinolophus sp.: Unconfirmed horseshoe bat species
were observed at Caves 5, 7, 8 and 9. At Cave 5 a single horseshoe bat was briefly seen hanging from a wall,
flying off into the surrounding forest upon disturbance. At Cave 7 a small colony of
approximately 15 horseshoe bats were observed. An analysis of the calls recorded from
this group indicates that two distinct FM/CF/FM calls were being used, with the
mean CF components occurring at 34.2 kHz and 39.4 kHz. In addition, separate CF calls with a
mean frequency of 89.0 kHz were also recorded. The 34 and 39 kHz recordings most likely
represent natural variation between calls in the same species, and although
there are no published accounts of horseshoe bat calls occurring at this range
of frequencies within the Philippines, calls between 30–33 kHz have been
recorded from the Enormous-eared Horseshoe Bat R. philippinensis on
Bohol Island (J. Sedlock pers. comm. 03 November 2011). Fewer 89 kHz calls were recorded, but
when they did occur the timing was always perfectly matched with one of the
lower frequency calls. These
recordings may therefore simply represent additional harmonic components of the
lower frequency calls. Alternatively, they could represent separate calls from a different
species, such as R. virgo - in central Luzon,
calls from this species have been recorded between 83-88 kHz (Sedlock
2001). At Cave 8 a small group of
three horseshoe bats was observed, from which short CF calls with a mean frequency
of 69.2 kHz were recorded. In
central Luzon calls from R. arcuatus have been recorded between
67–72 kHz (Sedlock 2001), suggesting that the bats observed in this cave
may have been that species. At Cave
9 a small group of three horseshoe bats was observed, from which short CF calls
with a mean frequency of 83.2 kHz were recorded, suggesting they were R. virgo (again compared with calls recorded by Sedlock
2001).
Based on the
above it is concluded that during the present study at least three horseshoe
species were encountered - R. virgo (visually confirmed in Cave 1 and
potentially accounting for the 83–89 kHz calls recorded in Caves 7 and 9)
and R. arcuatus (visually confirmed in Cave 6 and potentially accounting
for the 69 kHz calls recorded in Cave 8), along with a different unconfirmed
species (such as R. philippinensis) echolocating between 33–40 kHz
in Cave 7.
Vespertilionidae
Myotis sp.: At Cave 14 a group of five bats
were observed hanging free on the wall at the cave entrance in direct
light. These were either M.
horsfieldii or M. macrotarsus, but without a forearm measurement,
species-level identification couldn’t be confirmed.
Miniopterus sp.: At Cave 14 four bats were found at
the back of the cave in the twilight zone, hanging free and tucked into shallow
crevices. Three flew out upon
disturbance, but one was still torpid. This individual was carefully examined to confirm the presence of wing characteristics which are diagnostic of this family/genera,
although forearm measurements could not be taken to confirm species-level
identification.
Microbat sp.
At Cave 6 a
small group of bats (approx 20 individuals) was briefly observed hanging from
the entrance into the first large cavern before flying off. Based on the
previous encounter with Miniopterus sp. at Cave 14, the general
indication of size and shape observed suggested the bats were of that genus;
however without any reliable evidence, identification, even to family level,
could not be confirmed. At Cave 7 a
small clump of bats was observed high up around stalactites in the twilight
zone at the tunnel entrance, and a scattering of individuals were also seen
high up on the ceiling of the main cavern. At Cave 18 a single individual of another microbat species was seen
roosting within a crevice in amongst T. melanopogon. From the facial features that could be
seen the bat appeared to be a freetail bat (Mollosidae sp.); however the
sighting was brief and obscured, and so identification, even to family level,
could not be confirmed. At Cave 21
a single microbat was briefly seen flying around inaccessible chambers high up
in the main cavern.
Whilst no
bats were observed at Caves 2 and 3, fresh piles of bat guano were recorded.
Individual droppings crumbled to dust when pinched, revealing insect fragments
and confirming that these were from insectivorous bats.
Discussion
Species observations
During the
five weeks of surveys, 21 caves were visited across western Panay, of which 17
were confirmed to have bats present and a further two showed evidence of recent
occupancy. Of the species
confirmed, all were previously known to occur on Panay Island (see Heaney et
al. 2010), and many of the observations reflect existing knowledge of species
status and distribution across the Philippines and wider South-east Asia
(Csorba et al. 2008; Heaney et al. 2010). However, significant findings during the study included newly documented
maternity roosting sites of conservation importance for R. amplexicaudatusand H. ater, confirmation of cave-roosting behaviour on the island for C.
brachyotis, and observations of M. spasma co-habiting with a range
of other bat species. Further detailed discussions of these findings are
provided below.
Rousettus
amplexicaudatus: This is
a locally abundant species across South-east Asia and the Philippines (Csorba
et al. 2008), most commonly occurring within agricultural and residential land,
rarely found in forest, and known to roost in large groups of up to 100,000
individuals (Heaney et al. 2010). On Negros Island, the species has been found to have two birth periods
in each year, centred on March or April and August or September (Heideman &
Utzurrum 2003). The observations at
Caves 4 and 7 in Libertad (colonies of <10,000 bats, with young present
during April 2011, located in secondary forest near to human habitation), while
being important, are therefore as typically described for this species. In contrast, the maternity colony
observed in Cave 16, also during April, is located deep within the primary
forest of the Central Panay Mountain Range and supports at least 198,000
individuals (likely to be an under-estimate given that only a partial emergence
survey of the cave system was undertaken). During a previous PSDCF expedition to the cave, another group of
volunteers also conducted an emergence survey and estimated the cave population
to be 500,000 (R. Galang pers. comm. 24 April 2011). However, there is no record of the methodology
used, and based on existing colony descriptions for this species this figure is
possibly an over-estimate. An
exceptionally large colony of 1.8 million individuals is known for this species
in the Philippines at Monfort Cave in Mindanao, with the size of the colony
resulting from bats being forced into the safety of this protected site from
surrounding caves through hunting pressure (Locke 2006). Cave 16 nevertheless appears to
represent an unusually large colony of R. amplexicaudatus, located outside
of its typical habitat. The most
likely explanation for the location and size of this colony is the relative
safety afforded by the remoteness of the cave. While the conservation status of the
species is currently of Least Concern (Csorba et al. 2008), it would appear
that the importance of the colony in national (if not global) terms, along with
the anecdotal reports from local guides of a recent decline in the population
due to increased hunting from surrounding barangays, warrants the undertaking of
further study and implementation of protective conservation measures.
At all the
caves, there was potential for other fruit bat species, such as E. spelaea,
to be present within the colonies. However, during emergence surveys, echolocation calls were detected from
most bats seen emerging over the entire emergence period, indicating that R.
amplexicaudatus was the predominant, if not only fruit bat species present.
Hipposideros
ater: This is a
widespread species occurring from India to Australia (Csorba et al. 2008). It roosts in caves in primary and
secondary forest and in agricultural areas, with colony sizes between
300–500 individuals known to occur (Bonaccorso 1998; Churchill 2008;
Heaney et al. 2010). In the
Philippines, the species is not commonly encountered (Csorba et al. 2008). The timing of reproduction varies
geographically - in Australia, pregnant females are pregnant by June, and young
are born between October and December (Churchill 2008);in the Philippines, pregnant females have been recorded on Catanduanes Island
during February (Heaney et al. 1991) and on Palawan during May (Esselstyn et
al. 2004). The observations of very
young pups in Caves 6 and 20 during early May suggest that the phenology of H.
ater on Panay Island is similar to that recorded on Catanduanes
Island. The size of the observed
colony (approx. 200 bats) in Cave 20 in Barbaza is as typically described,
although it would appear to be important in the context of the status of the
species in the Philippines. However, the mixed-species colony of thousands of bats observed in Cave
6 in Libertad, comprising predominantly of H. ater, appears to represent
one of the largest documented for this species. The most likely explanation for the size
of the colony is the lack of disturbance due to the difficulty of entering the
cave combined with the location of the main caverns, deep inside the complex
cave system. While the conservation
status of the species is currently of Least Concern (Csorba et al. 2008), it
would appear that the importance of the colony in national (if not global) terms, warrants the undertaking of further study and
implementation of protective conservation measures.
Cynopterus
brachyotis: The
taxonomic status of this species is unclear, but it appears to represent a
species-complex of six distinct geographical lineages (Campbell et al.
2004). Within the Philippines the
complex is represented by an endemic Philippine lineage as well as the more
widely distributed Sunda lineage, which in the Philippines only occurs on
Palawan (Campbell et al. 2004). It
is an abundant species of disturbed lowland habitats, including residential,
agricultural, and urban areas (Heaney et al. 2010). It is often found roosting in palm
trees, and is known to shelter beneath fronds whichhave been modified through tent-making behaviour (Tan et al. 1997). According to Esselstyn et al. (2004),
the species occasionally roosts in caves in Borneo and Palawan, although this
behaviour had not been observed in the endemic lineage of the oceanic
Philippines. More recently, small numbers of C. brachyotis have been
observed roosting in a cave on Danjugan Island, just off the southwest coast of
Negros Island (O’Malley et al. 2006). During the present study small numbers (≤5) of C. brachyotis were
confirmed roosting in three caves on Panay Island, in both single and
mixed-species colonies. These are
the first recorded observations of cave-roosting for
this species on Panay Island, providing further evidence that this behaviour
occurs in the endemic Philippine lineage, and suggests it is a relatively
common occurrence, at least within the Greater Negros-Panay Faunal Region.
Megaderma
spasma: This is a widely
distributed species of South Asia and South-east Asia (Csorba et al. 2008),
recorded across the Philippines in bamboo thicket, mixed agro-forest, secondary
forest, and primary forest habitat, usually found roosting in small groups in
caves, tree-hollows, and hollow logs (Heaney et al. 2010). They are usually the sole occupant of their retreat (Nowak 1994), although they have
been observed roosting in caves with other species (Esselstyn et al.
2004). During the present study M.
spasma was the most frequently encountered species, confirmed at five of
the 17 caves where bats were recorded as being present. The largest group
encountered (15 individuals) were the sole occupants of a small undisturbed
cave (Cave 13) in a large predominantly disused/overgrown coastal garden in
Libertad, and the cave potentially represents a local maternity roosting site
for the species. At other caves
this species was recorded in lower numbers, but all were in association with
other species, including small numbers of E. alecto(Cave 10), C. brachyotis (Cave 9) and Rhinolophus sp. (Caves 5
and 9), and a large maternity roost of H. ater (Cave 20). In all cases there was segregation
between species, with M. spasma occupying either distinct areas of a
cave, or separate caverns. Animals
were frequently encountered roost-ing individually or in small numbers, but
huddling together upon disturbance, a behaviour whichhas been observed elsewhere (Csorba et al. 2008).
Current threats
During the
current study, a range of human pressures were either directly observed or
identified through discussions with local people which could pose a threat to
existing cave bat populations, including harvesting of bats for food,
disturbance (through activities including tourism, local cultural use,
anti-social behaviour and treasure-hunting) and potential future land-use
changes resulting from development.
For the
majority of caves visited, the impacts of these pressures currently appear to
be limited in extent. There are a number of potential reasons for this; many of
the caves are sufficiently remote (Caves 1, 4 and 16), difficult to get into
(Caves 6 and 15), difficult to find, even with guides (Caves 15, 20, 21 and
other reported caves in Barbaza that couldn’t be found), or located in private
property (Caves 10–13 and 15). Bat harvesting does appear to pose a more serious threat to the
important colony of R. amplexicaudatus present at Cave 16 within the
Central Panay Mountain Range, given the suggested recent increase in this
activity reported by locals. However, the reported cessation of harvesting at Cave 4 in Libertad
indicates that locals do understand the consequences of harvesting and are
taking responsible steps to prevent and reverse historic impacts. Although the harvesting of bat guano has
been identified as one of the major threats to cave bats in South-east Asia
(Al-Mateen et al. 2011), this activity was not recorded during the current
study.
Tourism
within Panay is currently limited to Boracay Island, off the north coast of the
Northwest Panay Peninsula. Here, the development pressure associated with
tourism (land take, increased disturbance) has had negative effects on island’s
fauna and flora (including bats), and sustainable management of the remaining
biodiversity asset is an ongoing challenge (e.g., Luft & Meier 1999; van
der Aa et al. 2006). However,
mainland Panay is becoming increasingly more accessible to the foreign
traveller; for example, during the current study, a project to completely pave
the existing coastal road around the Northwest Panay Peninsula was well
underway, and it was evident that the municipality of Libertad has aspirations
to develop it’s potential as a tourist destination, with an eco-tourist
accommodation building project currently in progress. Development could negatively impact on
local bat cave populations, both directly (such as at Caves 10 and 12, where
the land in which the caves are located was historically allocated for hotel
development) and indirectly, through increased tourist visits to well-known and
easily accessible caves (such as at Cave 7). However, if well-planned and undertaken
sensitively and with due consideration to bat populations, tourism could help
to protect cave bats by providing new and alternative sources of income to
local people, as well as supporting organisations currently undertaking
research and educational activities on Panay which are beneficial to cave bat
conservation.
Conclusions
The present
study represents the first attempt to record species composition and colony
estimates of bats within caves on Panay Island, as well as documenting existing
and potential future threats to these populations. Based on the information collected so
far, recommended priorities for future work are as follows:
Further baseline studies
Some of the
larger caves in Libertad (Caves 6, 8 and 15), as well as the cave complex in
the Central Panay Mountain Range (Cave 16), have only been partially explored,
so further visits should be undertaken to enable a comprehensive assessment of
the cave structures and the extent to which they are used by bats (including
confirmation of all species present). In addition, where larger colonies have
either been observed (Cave 6) or are likely to occur (Cave 15), baseline
emergence surveys should be undertaken at cave entrances to quantify the
numbers of bats present. A more
robust and standardised emergence survey method should also be devised for the
Cave 16 complex to enable an accurate estimate of this important population.
However,
beyond cave-specific recommendations, there is a wider need to assess bat
populations within all caves on Panay Island. The first obvious step towards this goal
would be to establish a more co-ordinated, comprehensive cave assessment
programme for a specific geographic area, such as the entire Northwest Panay
Peninsula.
Regular monitoring of key sites
Ideally, all
confirmed bat caves should be monitored on a regular basis, and certainly those
caves either confirmed or suspected of supporting breeding colonies (as
indicated in Tables 1 and 2). Monitoring should seek to detect any changes in bat populations (through
the undertaking of repeatable standard methods employed during baseline
studies) and be able to relate any changes observed (whether negative or
positive) to identified human pressures. Where resources are limited, priority
should be given to monitoring the breeding colonies of R. amplexicaudatusat Caves 4, 7 and 16, as bat harvesting and disturbance from tourism have
already been identified as existing pressures whichmay be impacting on these populations.
Developing a local echolocation call
library
During the
present study a limited amount of opportunistic echolocation call data was
collected as a tool to aid with species identification. Whilst this data did
provide some additional information (particularly regarding horseshoe bats),
the recording of echolocation calls is currently of limited use as a surveying
technique due to the lack of reference call libraries with which collected data
can be compared (Sedlock 2001). There is therefore an urgent need to begin compiling a local reference
call library for Panay, using calls recorded under more standardised
conditions.
Protection of key sites and managing
threats and pressures
Cave 16
within the Central Panay Mountain Range supports a significantly large fruit
bat colony which is currently under threat from
increased bat harvesting. This cave
therefore appears to be of sufficient importance to warrant inclusion within a
protected area, and the information collected so far should therefore be fed
into current work being undertaken by the Haribon Foundation to expand the
existing boundaries of the Central Panay Mountain Range protected area. However, as has already been
highlighted, on its own the protected areas system currently receives insufficient
funding to ensure that effective conservation measures are undertaken. In addition there is therefore a need to
educate and work with local barangays to ideally stop, or at least reduce the
level of bat harvesting at the cave. There is also some potential for establishing the cave as a more extreme
tourist attraction, offering a combination of rainforest hiking, river rafting,
wildlife watching, and a unique cultural experience - if this was implemented
sensitively, it could help with the cave’s protection by providing an
alternative economic benefit to the local barangays (through employment of
guides, provision of accommodation etc).
More widely
there is a need to raise awareness about the conservation of bats and the
importance of local cave systems for their survival with local communities and
governments, and to provide advice on sustainable cave management. For example, discussing the need to
regulate visits to Cave 7 in Libertad with the municipality environment
officer, and exploring opportunities for positive, long-term stewardship of Caves
10–13 and 15 with the private landowner. Organisations such as PSDCF are well
placed to facilitate these actions on the ground, and bat research and
education activities could be built into a regular programme of work involving
both local groups and international volunteers. However, such activities should not be
undertaken in isolation, but rather they should be implemented in a
co-ordinated approach with other organisations, such as Bat Conservation International
(BCI) and the Southeast Asian Bat Conservation and Research Unit, who have
shared aspirations for bat conservation and are already developing and
implementing complimentary work programmes. BCI has initiated a specific work
programme focused on supporting efforts to conserve cave-bats of the
Philippines, and there are potential opportunities for the sharing of
information, experiences and expertise, such as through the Philippine Caves
and Bats website <https://phcavebats.crowdmap.com>.
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