Through The Backyards;

Small Mammal Research! (:

Here's a post dedicated to Amanda,

and BoyBoy (a female actually) after much procrastination, in view of having recently concluded my volunteering stint with her!

 

Amanda's honours project is a baseline study for NParks' Eco-Link project. The Eco-Link project seeks to address biodiversity-related issues by bridging adjacent plots of forests – BTNR and CCNR, 

which was previously a continuous patch of forest (before it was fragmented in 1986 to make way for development).

The construction of the Bukit Timah Expressway (BKE) subjects sensitive landscape areas to edge effect:

• Abiotic – involve changes in the microclimatic stresses (e.g. increased light, elevated air and soil temperatures, increased nutrient, increased moisture stress)
• Biotic (direct) – involve changes in vegetation diversity and wildlife implication (e.g. weed abundance, roadkills)
• Biotic (indirect) – involve changes in species interactions (e.g. predation, parasitism, pollination and seed dispersal)

The BKE also effectively bisected arboreal-terrestrial forest communities, resulting in species isolation (which may promote inbreeding, reducing the fitness and hence survival of a species). 

Driven by the 5 strategies listed in the National Biodiversity Strategy and Action Plan (NBSAP),

"... NParks will be developing an Eco-Link across the BKE, in the form of an overhead bridge to connect the Bukit Timah and Central Catchment Nature Reserves. With a width of 50-metres at its narrowest point, this hourglass shaped bridge will be densely planted with vegetation to encourage animal crossings between the two nature reserves. Not only will the Eco-Link benefit the wildlife, people will also be able to enjoy extended hikes between the two nature reserves via trails on the new link. The first of its kind in Southeast Asia, this overhead Eco-Link affirms the Government's commitment to the long-term conservation of Singapore's biodiversity." – Mr Mah Bow Tan (Minister for National Development)

Though we all know that it would have been more effective to plan to retain linkages in a landscape than to attempt to re-establish them in a previously fragmented landscape, hopefully this $17, 000, 000 ecological corridor, upon completion, can meet its objective of ensuring the exchange of genetic material, adequate feeding areas and breeding grounds. More on the Eco-Link

 

Back to Amanda's project! In which, she studies the population and distribution of small mammals at various locations within BTNR and CCNR.

When deciding on a suitable field technique, the size of the animal, its niche (i.e. arboreal, aquatic, subterranean, terrestrial, volant), and its behavior (e.g. nocturnal), are necessary considerations. In her case, field survey entails live-trapping of small mammals using baited Tomahawk and Sherman traps, coupled with the Mark-and-Recapture technique for a more qualitative analysis on the small mammal populations. More on survey techniques

Anyway, below is a series of photos which chronicles (more or less) her fieldwork. All photos taken with iPhone 4, and rather hastily so... sorry for the poor quality! 

She sets up 36 traps at every site. And each trap is placed 20m apart, alternating between Tomahawk and Sherman in the entire grid system. She also checks all 36 traps twice a day.

Singapore Rat (Rattus annandalei)

Besides the Singapore rat, she also caught the Malaysian Wood Rat (Rattus tiomanicus), Common Treeshrew (Tupaia glis), Hooded pitta (Pitta sordiad cucullata) and a baby monkey (long-tailed macaque I think)!

I'm thankful to have been given the opportunity to help her (and other honours students) during these two months! The experiences have been rewarding and I've definitely picked up some skills (like setting the camera traps, micro-chipping and using the total station).

 

References:

1. Laurance WF, Nascimento HEM, Laurance SG, Andrade A, Ewers RM, et al. 2007 Habitat Fragmentation, Variable Edge Effects, and the Landscape-Divergence Hypothesis.PLoS ONE 2(10): e1017. doi:10.1371/journal.pone.0001017
2. Good, J. A. (1998) The potential role of ecological corridors for habitat conservation in Ireland: areview. Irish Wildlife Manuals, No. 2, 72pp.

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Further Readings:

• Study uncovers how animals in Maryland use underground highway culverts (More photos on their FB page)
• Conservation Buffers: Design Guidelines for Buffers, Corridors, and Greenways by National Agroforestry Centre
• The role of corridors and types
• An analysis on the effectiveness of different traps

Wild Pigs fieldwork! (:

December has been quite exciting.

 

When I first indicated my interest as a field assistant for NUS Honours students with their final year project, I didn’t know what to expect, or if I were up to the task. I only formally knew what I had to do when the undergrads. themselves contacted me through email; after all, the projects they were embarking on were different and the fieldwork itself had varying degrees of demand and intensity. And since I didn’t have any vacation plans, and had nothing substantial enough in my Google calendar to regard as “Important”, I filled in multiple Google forms and signed myself up for a month of fieldwork!

 

The first undergrad. I tagged along with assisted is currently doing a study on Sus scrofa, the Eurasian wild pig. I’ve seen them only at Chek Jawa. (Excuse the quality, it was really dark and the photo was taken using an iPhone.)

 

 

Over the course of 4 sessions (minus 3, because the weather forecast is not exactly accurate), we covered Bukit Batok Hillside Park (more of a recce trip), CCNR (Woodcutter’s trail) and explored the Kent Ridge forest patch (beside Science Park II and along South Buona Vista Road). Basically, fieldwork with Say Lin entails trekking and looking out for field signs that indicate pig presence, and the setting up of camera traps at impacted sites. Though distinctive and identifiable, I tend to confuse pig hoof prints with erosion patterns, and get excited for nothing. *ashamed* This problem can be eliminated rather easily – just see if you can trace the prints, to form a trail… Then again, we went in circles while tracing a pig track at Kent Ridge.

 

They just disappeared. 
Pigs can fly.

 

Their tracks were probably erased after days of rainfall and buried under heaps of leaf litter. Other signs of pig activity in the vicinity include rooting, digging and mud wallows and mud rubs on trees. They also leave traces of ‘Graffiti’ on trees (Aspiring artists or scent marking behaviour of male wild pigs? You decide!), as Say Lin puts. We also noticed that they tend to hang around streams or areas with rattan palms, like the Elaeiodoxa conferta (along the Woodcutter’s trail) and a few other species. (I’m not familiar with plants >< so uh, I’ll remember take pictures next time!)

 

Taken at Bukit Batok Hillside Park

 

So why study the density and distribution of wild pigs? Pigs’ foraging habits can result in potential ecological damage.  Their foraging behaviours, such as rooting and digging, can alter water quality (due to increased soil erosion) and patterns of forest succession (by preferentially uprooting dipterocarp saplings for nest-building and encouraging the dispersion of invasives like Koster’s curse, impeding succession from Stage 2 to 3). Apparently, besides Man, they are the greatest vertebrate modifier of natural communities (both vegetation diversity and animals communities)! More

 

Apart from the only known extant predator – the reticulated python (Python reticulatus), the wild pigs experience virtually little or no predation pressure on mainland Singapore. Given suitable habitat and food availability (they’re opportunists, and have a varied diet – they even chew roots and consume the sap and starches before expelling the masticated balls of woody tissue), it is likely that their population will increase in size in the near future. In light of this, more studies have to be done to address, if not prevent, potential human-wildlife conflicts.

 

Below are just screenshots of Google Earth street view:

PGP residential - A place we walked through a few times in our muddy gear.

 

South Buona Vista Road - where we entered/exited the forest patch and where the SBS bus uncle cheated us, only to discover a mountain biking trail & no signs of pig activity. This was also where I confused erosion patterns with pig hoof prints.

 

The 'sleeping man place' -  We entered/exited the forest from here too.

 

 

Other wildlife: 

 

 

We encountered a strange-looking millipede/centipede (Say Lin has a photo of it), Hammerhead flatworm, Branded Imperial, Common Mormon, the usual butterflies and skippers, lots of grasshoppers and katydids, a strange looking caterpillar (black with orange and yellow bits fringing its body -  *Edit: It's not a caterpillar, but a beetle larva), earthworms, birds, and swarms of giant soldier termites while bashing trekking through the forest. There are probably a lot more we saw that I didn't mention here. No pictures either, sorry! (We were busy with fieldwork.)

 

Here's a fungi for you!

 

During this short stint, I’ve learnt how the camera trap works. :D And how to identify impacted sites. I’ll probably be tagging along for more wild pigs fieldwork in the future if my schedule permits…  As for now, I’m looking forward to helping the others with theirs, since I’ve signed up already. Hopefully, I’ll be updating this blog more frequently this month! More stories to tell!

 

 

References:

Ditchkoff, S. S., and J. J. Mayer.  2009.  Wild pig food habits.  Pages 105-143 in J. J. Mayer and I. L. Brisbin, Jr. (eds.) Wild pigs: biology, damage, control techniques, and management.  Savannah River National Laboratory, Aiken, SC. (SRNL-RP-2009-00869). https://fp.auburn.edu/sfws/ditchkoff/PDF%20publications/Food%20Habits%20Chapter%20-%20Wild%20Pig%20Book.pdf

West, B. C., Cooper, A. L., and Armstrong, J. B. 2009. Managing wild pigs: A technical guide. Human-Wildlife Interactions Monograph 1: 1–55. http://www.aphis.usda.gov/wildlife_damage/feral_swine/pdfs/managing-feral-pigs.pdf

Yong, D. L., Lee, B. P. Y-H., Ang, A., and Tan, K. H. 2010. The Status on Singapore Island of The Eurasian Wild Pig Sus scofa (Mammalia: Suidae). Nature in Singapore 2010 3: 227-237. http://rmbr.nus.edu.sg/nis/bulletin2010/2010nis227-237.pdf

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*Sun, 25 Dec 2011 12:58:32 +0800

late-night

Greetings, lost friend.

If you look closely, you'll see that it's grasping on a stalk of grass. :D :D So cute amiright.

Back where you belong, hurray!