Our Projects

Invertebrates

Carnivorous caterpillars: understanding diet and symbiosis in Singapore's lycaenid butterflies

Principal investigator: Dr. Melissa Whitaker – 2014 WRSCF grant recipient

A small green Common Red Flash (Rapala iarbus) larva feeding on flower buds with a single ant in attendance

Wildlife Reserves Singapore Conservation Fund (WRSCF) is providing funding support to Dr. Melissa Whitaker from Harvard University, Museum of Comparative Zoology for her research on the ecology and evolution of lycaenid, or gossamer-winged butterflies.

These butterflies have specialised life histories with ants from their larval stages, which may predispose them to rarity and endangerment. Unfortunately, for many lycaenid species in Singapore and worldwide, even basic life history information is unknown to science.

With the aim of addressing these knowledge gaps, Dr. Melissa Whitaker is studying and collecting carnivorous caterpillars in Singapore to explore factors that determine their diet and symbiosis with ants. This project is conducted in collaboration with the local conservation group, Butterfly Circle.

Saving the Singapore Freshwater Crab (Johora singaporensis) from extinction

Principal investigator: Dr. Daniel Ng Jia Jun – 2013 WRSCF grant recipient

WRSCF is supporting a project by Daniel Ng from the National University of Singapore (NUS) to study various aspects of ecology of the globally critically endangered Singapore Freshwater Crab. This species is one of few that is endemic to Singapore, only known from three small streams in the island and is in the top 100 most threatened species in the world!

Findings from the study will subsequently be used to establish new populations by introducing the species to new suitable sites. The most suitable site for translocation has been selected and trials are currently being conducted for the translocation.

The feasibility of establishing an ex-situ population is also being investigated and offspring from captive individuals may be used to boost existing wild populations. Research outcomes could shed significant information about their biology and contribute greatly to conservation efforts.

Evaluating the Success of Coral Reef Restoration in Singapore

Principal investigator: Lionel Ng Chin Soon – 2013 WRSCF grant recipient

Gravid Acropora sp. colony with egg bundles

Reef Enhancement Unit with a diversity of sessile life forms

Various attempts at reef restoration, including artificial reef structures deployed on reefs at Singapore’s southern offshore islands and coral transplants on various reefs and seawalls have been carried out in the past two decades, but the long term outcomes of these efforts have not been monitored. A study was hence initiated by Lionel Ng from NUS and supported by WRSCF to evaluate if the artificial reef structures and coral transplants have established themselves at Singapore’s offshore islands and provided ecosystem services, such as habitat creation or contribution of larval supplies during the annual mass coral spawning events.

Findings from the study demonstrate that it is feasible to deploy fibreglass artificial reef units on Singapore’s reefs to boost the recruitment and establishment of reef fauna, and indicate that future coral transplantation protocols can also be refined in terms of choice of transplant site, methods, and coral species used. The importance of conducting long term monitoring to fully assess the effectiveness of coral reef restoration efforts is emphasized.

Habitat enrichment for tropical butterflies in forest and urban landscapes

Principal investigator: Anuj Jain – 2013 WRSCF grant recipient

A marked Purple Duke (Eulaceura osteria kumana) butterfly recaptured feeding on flowering Syzygium tree

A marked Common Mormon (Papilio polytes) butterfly with a Singapore five cents coin for scale

Habitat degradation and fragmentation in the tropics, especially in South East Asia, poses great threat to tropical species, especially forest dependant insects as they lose original habitat and are often unable to colonise degraded habitats that lack resources specific to their species. If scarce resources indeed limit populations, then chances of survival of these species can be improved by enhancing habitats with key resources.

By using Singapore as modal system, the study by Anuj Jain from NUS first maps hotspots of butterfly diversity in Singapore, identifies areas which hold species of conservation concern and hypothesizes bottlenecks for the survival and reproduction for rare and threatened butterfly species. Mark-recapture techniques are then used to evaluate the effect of habitat type on the home range of butterflies, after which a habitat enrichment strategy using larval host plants (juvenile food resource) and nectar plants (adult food resource) will be implemented to maximize populations in native habitat and improve the quality of degraded habitats. Predator exclusion experiments are also being conducted to deduce potential predators. This will quantify the effects of habitat enrichment for butterflies in the tropics so that specific recommendations can be developed for conservation planning. Finally, the WRSCF sponsored project aims to determine whether creating resource-rich stepping stones can increase exchange between forest fragments and in turn increase long term viability of fragmented populations.

Rearing coral larvae for reef restoration: Examining the effects of nutrition enhancement on post-settlement survivorship

Principal Investigator: Dr. Toh Tai Chong – 2012 WRSCF grant recipient

Settlement of coral recruits (approximately 1mm in diameter) on cement substrate

Fed coral recruit at 6 months post-settlement

Studies have shown that the mortality rates of stony coral transplants are influenced by their size, where inducing early growth rates in juvenile corals can potentially increase survivorship on the reefs. A study by Toh Tai Chong from NUS, with the support of WRSCF studied the effect of feeding cauliflower coral (Pocillopora damicornis) recruits with live brine shrimp larvae (Artemia salina nauplii) at varying densities over half a year in ex situ aquaria. The hard coral juveniles were then transplanted to local reefs, where they were monitored for another 6 months.

The behavioural observations made in this study revealed that via tentacular capture, cauliflower corals juveniles were capable of immobilizing and consuming planktonic live feed even just a few days after being settled in the ex situ facility, proving that coral juveniles developed functional feeding apparatus early in the developmental stage to increase their ability to feed on various organisms. The project also showed that coral growth rates increased after the juveniles have been fed with live zooplankton for 6 months in the facility and this increase persisted even after transplantation to the reef. The fed corals also displayed significantly higher survival rates than the unfed ones.

This is the first study to explore the potential long-term benefits of nutrition enhancement and associated growth induction on coral transplant survivorship. The results from this study have been published in 3 international peer-reviewed journals and 1 conference proceeding.

Herpetofauna

Spatial Ecology of the Reticulated Python (Malayopython reticulatus) in Urban Singapore

Principal investigator: Mary-Ruth Low – 2013 WRSCF grant recipient

Reticulated python (Malayopython reticulatus) being released after transmitter was implanted [©Nathanael Maury]

Based on an existing “mark-and-release” programme at the Singapore Zoo, it appears that reticulated pythons have strong homing instincts as they regularly return to their initial capture site after being released at a different location. These snakes are measured and marked with a passive inductive transponder (PIT) tag after being captured, often in housing compounds and industrial warehouses in Singapore, and then translocated to secondary forest or wasteland areas away from densely populated areas. Little is known about their movement in the wild however.

With funding support from WRSCF, Mary-Ruth Low from the National University of Singapore (NUS) is using radio- and GPS-telemetry to obtain a greater understanding of the spatial ecology of these snakes. This will enable better conservation and relocation strategies to reduce potential human-wildlife conflict and also generate more effective prevention strategies in keeping snakes from re-entering their initial capture sites.

Effects of habitat disturbance on canopy amphibians and reptiles in Southeast Asia

Principal investigator: Dr. Brett R. Scheffers – 2010 WRSCF grant recipient

Malayan horned frog (Megophrys nasutus) located on the ground during night surveys at Bukit Timah Nature Reserve

Red-tailed green rat snake (Gonyosoma oxycephalum) found at 35m in the rainforest canopy of Singapore

WRSCF is supporting a project by Daniel Ng from the National University of Singapore (NUS) to study various aspects of ecology of the globally critically endangered Singapore Freshwater Crab. This species is one of few that is endemic to Singapore, only known from three small streams in the island and is in the top 100 most threatened species in the world!

Findings from the study will subsequently be used to establish new populations by introducing the species to new suitable sites. The most suitable site for translocation has been selected and trials are currently being conducted for the translocation.

The feasibility of establishing an ex-situ population is also being investigated and offspring from captive individuals may be used to boost existing wild populations. Research outcomes could shed significant information about their biology and contribute greatly to conservation efforts.

Birds

Long term population viability of four species of babblers of Singapore

Principal investigator: Cros Emilie Sidonie – 2013 WRSCF grant recipient

Chestnut-winged babbler (Stachyris erythroptera)

South East Asia is a hotspot for globally threatened bird species, with habitat fragmentation thought to be one of the main causes of local bird species extinction. “On top of diminishing population sizes, habitat conversion also reduces gene flow and connectivity between populations, which then may lead to inbreeding and a reduction in genetic diversity that is essential for adapting to potential changes in the environment in future.

Understorey birds, such as babblers are known to be particularly vulnerable to habitat fragmentation. Only 4 babbler species are still found in Singapore, namely the short-tailed babbler (Pellorneum malaccensis), pin-striped tit-babbler (Mixornis gularis), Abbott’s babbler (Malacocincla abbotti) and chestnut-winged babbler (Cyanoderma erythropterum).

This study by Cros Emilie from the National University of Singapore (NUS), supported financially by WRSCF, aims to analyse the genetic diversity of the populations of these birds to determine patterns of connectivity and gene flow and to assess the viability of their populations. Understanding how modifications to their habitat affect the birds is crucial for implementing appropriate measures for their conservation to prevent further extinctions.

Mammals

The urban ecology of bats in Singapore: understanding the human-wildlife interface

Principal investigator: Benjamin Lee – 2013 WRSCF grant recipient

Collection of environmental data with a data-logger and recording calls in the roost of the Ashy Roundleaf Bat (Hipposideros cineraceous)

Whiskered Myotis (Myotis muricola) roosting in a curled up banana leaf

Bats provide valuable ecosystem services, for instance insect pest suppression and pollination, but land-use change in Singapore has unfortunately led to a severe drop in bat species diversity by as much as 60% for fruit bats and 75% for insectivorous bats. Being an inconspicuous mammal, bats have largely been neglected in studies of urban wildlife ecology and our understanding of the impact that urbanisation has on bats is severely limited.

The research being undertaken by Benjamin Lee from the Durrell Institute of Conservation and Ecology (based at University of Kent) hence strives to determine the bat species persisting in urban environments and the reasons for their survival. This WRSCF funded project also aims to assess the effects of major roads on bat diversity and activity, and to find out the habitat value of green roofs for bats in an urban environment. An implicit output from this research project is a call library for the echolocating bats of Singapore.

Given the lack of urban ecological studies in tropical Asia, this research will be a valuable contribution to a much-needed evidence base for the development of pertinent conservation management and policy initiatives in the urban environment.

Research and conservation of the common palm civet, Paradoxurus hermaphroditus Pallas, 1777 (Mammalia: Carnivora: Viverridae) in Singapore

Principal investigator: Fung Tze Kwan – 2013 WRSCF grant recipient

Common palm civet (Paradoxurus hermaphroditus) caught on camera trap on Pulau Ubin.

Civet scat with germinating seeds on Pulau Ubin

Tracking the common palm civets using radio-telemetry [©Gladys Chua]

WRSCF issued a grant to a multi-component research project by Fung Tze Kwan, together with N. Sivasothi and Xu Weiting from the National University of Singapore (NUS), and Dr. Christina Colon from Kingsborough Community College, City University of New York on the ecology of the common palm civet, an iconic and adaptable native carnivore found in both forested and urban environments in Singapore.

The study aims to investigate the feeding ecology of the common palm civets in relation to their home range and habitat utilisation via the use of GPS collars and scat analysis to determine the seed dispersal role they play in forest regeneration. The fate of translocated urban civets are also being tracked via radio collars upon release to examine their movement patterns. In Singapore, common palm civets which are found living in close proximity to humans have unfortunately brought about complaints from a minority group, leading to cases of human-civet conflict. Thus, this project also works on the development of conflict management and conservation strategies that can be applied to Singapore as well as Southeast Asia.

Singapore is leading the call to enhance biodiversity in cities and a grasp of the ecology of urban survivors is critical to facilitate co-existence with local wildlife.

The Ecology and Conservation of the Leopard Cat Prionailurus bengalensis (Kerr, 1792) (Mammalia: Carnivora: Felidae) in Singapore

Principal Investigator: Chua Aik Hwee Marcus – 2011 WRSCF grant recipient

Leopard cat on Pulau Tekong

Servicing a camera trap in the field [©Kelvin Lim]

Prior to the study, the nationally critically endangered leopard cat (Prionailurus bengalensis) was last seen alive in the wild on mainland Singapore in 1968. Little is known about the ecology of the species in Singapore and in human-modified habitats in the region. With the aim to contribute to the conservation efforts of Singapore’s last wild cat, various aspects of the ecology and population genetics of this species in major forest fragments in Singapore were examined by Marcus Chua from NUS with funding support from WRSCF.

Surveys revealed the first live leopard cat in the wild on the main island of Singapore since 1968, and a population present in the Western Catchment was confirmed. Autecology and genetic studies focused on the population present on Pulau Tekong, establishing a baseline knowledge and providing a better understanding of the status of leopard cats in the country. Genetic variation in the Pulau Tekong population was however, revealed to be low, possibly due to genetic drift or a bottleneck.

Although leopard cats in the study have been found to be fairly tolerant of habitat disturbance, the status and future of the leopard cats of Singapore appears uncertain. The lack of legal protection from threats of proposed development, road mortalities, poaching, inbreeding depression and possible negative interactions with dogs, cats and wild pigs in its range are challenges to the long-term survival of the species in Singapore.

Multi-taxa

Biodiversity Surveys at WRS parks

Principal investigator: WRS Conservation & Research Department – 2013 WRSCF grant recipient

Members of the public joining WRS staff at the very first bird survey in the parks on International Day of Biological Diversity 2014, 22 May

Sunbeam snake (Xenopeltis unicolor) at Jurong Bird Park [©Mary-Ruth Low]

2011-2020 has been declared the United Nations Decade on Biodiversity. Joining in the world-wide efforts on understanding and increasing local biodiversity, WRS, with funding support from WRSCF, commenced regular community-based surveys in 2014 to further the understanding of Singapore fauna, conduct in-situ wildlife conservation, and increase biodiversity awareness in Singaporeans.

Understanding how local wildlife utilize the altered natural habitats of the WRS parks can have important implications for how fauna may use other altered habitats across Singapore, such as railway corridors or nature parks. Due to their location within the Central Catchment Nature Reserve, the three parks (Singapore Zoo, Night Safari and River Safari) represent an important wildlife corridor and unique foraging and breeding opportunities for certain species. Furthermore, the parks provide a unique opportunity for local Singaporeans to come close to native fauna that may not be found elsewhere in the country. Surveys at Jurong Bird Park (within an industrial precinct) may also reveal how local biodiversity can be encouraged in a disturbed and isolated habitat.

Three bird surveys, one amphibian survey and two herpetofauna surveys have been carried out over 2014 and 2015. These surveys revealed WRS parks to be biodiversity hotspots and to be home to more than 8 locally threatened species. Drop us a line if you would like to help out with our future surveys!

Accelerating Forest Recovery and Enhancing Wildlife Habitat in the Central Catchment Nature Reserve

Principal Investigator: Chua Siew Chin – 2011 WRSCF grant recipient

Field setup that measures relative humidity,
air temperature and soil moisture

Singapore’s Central Catchment Nature Reserve and Bukit Timah Nature Reserve encompass a mosaic of primary forests, slowly-recovering secondary forests, and fern-dominated areas. Assessments however, have shown that the regeneration of disturbed areas within this mosaic may have stagnated. Chua Siew Chin from the University of California sought to understand the ecological factors facilitating and retarding forest recovery in Singapore’s nature reserves. The WRSCF-supported project aimed to study the plant-trait mechanisms driving forest recovery and also to determine the role animal-mediated processes play in forest recovery.

Seedling and tree surveys were conducted on suitable research plots, and dung beetle and ant surveys in the secondary and primary forests were carried out in collaboration with NUS. Leaf samples from secondary forests were collected for plant functional trait analysis and environmental sensors were set up at all the sites. Findings were disseminated to local forest managers and members of the public to contribute towards the
conservation of Singapore’s natural heritage via aiding
forest recovery and enhancing wildlife habitats.

Biodiversity of vertebrate scavengers in Singapore: implications on conservation and nutrient cycling

Principal Investigator: Norman Lim T-Lon – 2011 WRSCF grant recipient

A monitor lizard (Varanus sp.) attracted to the chicken carcass placed in a metal cage

Abundant blowfly maggots in different sizes found in a chicken carcass not consumed by vertebrate scavengers

Secondary forests are often considered to have little conservation value and may consequently be cleared for development projects. Over 85% of the forested areas in Singapore are composed of secondary forests, so it is imperative to document the biodiversity residing in the various forest types to support the need for forest protection in Singapore. This project focused on the functions of scavengers in Singapore forests and the ecological role they play.

In addition to documenting the identities of the main scavengers in Singapore (including the discovery of Malay civet, Viverra tangalunga), findings from the study revealed that vertebrate scavengers have a positive impact on seed and seedling survival, but also that these species are often hunted and traded in large numbers (e.g. wild pigs and monitor lizards). Despite them not being of high conservation status, it is necessary to provide additional protection for Singapore’s vertebrate scavengers, particularly in areas of enforcement in illegal poaching and wildlife trade.