Another odonate survey with the gang, this time to the ponds of Marina East. The habitat is dominated by thin grass-like vegetation. Not very sure what plant it is but most probably belongs to the Cyperaceae family. The water itself is full of brownish algae and there’s a slight smell typical of eutrophic waters.
Nevertheless, this is an excellent habitat for odonates. They are in high abundance and are very active thanks to the warm morning sunshine. The most numerous species is Diplacodes nebulosa. They are very distinct due to the dark tips on their wings. All the males are defending a small territory and chasing each other, zipping all over the water surface.
The most striking dragonfly there has to be Rhyothemis triangularis, aptly named due to the deep metallic blue triangular patch on its hind wings. Dragonflies from the genus Rhyothemis characteristically have short abdomens with broad hind wings. Some of them are quite common in open countries or streams in swampy forest. R. triangularis is common and widespread in Asia. However in Singapore they are rather uncommon as habitats akin to the Marina East ponds are few and far between.
But odonates are not the only creatures inhabiting the ponds. From afar, a Lesser Whistling-duck (Dendrocygna javanica) made an appearance. This is a nationally vulnerable bird. Once again habitat loss is the main cause as freshwater ponds are destroyed when urbanisation encroaches. This bird has an estimated population of 250 in Singapore.
As we left Marina East, I sensed a “melancholy in the wind and sorrow in the grass” (Charles Kuralt). How much longer will this location remain as it is? Its neighbour at Marina South is already morphing into the Integrated Resort. Rumour has it that Marina East will become a golf course. “Another golf course?!” Tang sighed.Perhaps we could get the developers to build the golf course while preserving this small nature haven? My mind begins to sparkle…
Pictures taken at: Marina East, January 2008.
References:
Orr, A. G., 2005. Dragonflies of Peninsular Malaysia and Singapore, Natural History Publications (Borneo) Sdn. Bhd, Malaysia.
Wang, L. K. & C. J. Hails, 2007. ‘An annotated checklist of the birds of Singapore’, The Raffles Bulletin of Zoology, Supplement 15: 1-179.
The scenic Kranji Marshes hug along much of Kranji Reservoir’s perimeter. Marshlands are an increasingly rare habitat in Singapore as many have been lost to urban development.
Purple Swamphen is a member of the Rail family which also includes the more common White-breasted Waterhen (Amaurornis phoenicurus). They inhabit mostly swampy and marshy habitats. These birds have a clearly distinguishable robust stout body, short tail and are rather weak fliers. Their huge red bill, red frontal shield, red legs and purplish-blue plumage make them one of Singapore’s most attractive marshland birds.
Purple Swamphens have a very conspicuous white undertail covert. The birds will constantly flash this white rump patch by jerking their tail up and down. Research suggests that this behaviour is a form of prey-predator communication whereby a bird’s state of alertness is communicated to a potential predator, thus discouraging the predator from a vigilant prey. Perhaps that was exactly what the bird was trying to tell us that Christmas afternoon. We certainly would not have the heart to harm such a fine-looking creature. 
The cerata are actually respiratory organs. In certain species, a cnidosac occurs at the tip of each ceras. These functions as storage for nematocysts capsules for defence and many aeolids obtain the stinging nematocysts from their food source, for example hydroids.
This aeolid nudibranch spotted at Beting Bronok is an absolute attraction. It most probably is from the family Facelinidae. For exact identification to species, its radula would have to be examined.
Agriocnemis femina is a small damselfly measuring up to only about 17mm in body length. This species undergoes colour changes with maturity and mature males have a whitish synthorax. This dainty damselfly is common around ponds and drains and they share the same habitat with another damselfly species, Ceriagrion cerinorubellum. 
C. cerinorubellum is about a size bigger than A. femina. They are fierce predators and it was not long before we chanced upon a C. cerinorubellum attacking and consuming an A. femina. The prey’s head had been consumed but we could clearly see that it was an immature male A. femina from the orange tip at the abdomen. The C. cerinorubellum was so engrossed on lunch that it simply ignored me as I approached it really close to get a clear picture.
In nature, it is a case of eat or be eaten. This time the predator became the prey. A Lynx Spider (Oxyopes sp.) had captured a C. cerinorubellum. Lynx Spiders have keen eyesight and they hunt down their prey with very agile movements. This individual must have sprung an ambush on C. cerinorubellum which did not stand a chance once the spider sank in its fangs.
Stichopus herrmanni (greyish-green form)