Hello, seen any eagles or dolphins lately?

Two studies on dolphins and birds of prey may just throw light on health of environment
Grace Chua Straits Times 5 Mar 11;


Can you spot the dolphin? Researchers want to find out if local waters are part of some marine mammals' migratory routes. -- PHOTO: NUS' TROPICAL MARINE SCIENCE INSTITUTE

SEEN a dolphin in local waters or a bird of prey hovering over a reservoir? Researchers want to know.

The National University of Singapore (NUS) and the Nature Society Singapore (NSS) are separately conducting two studies on these creatures which could be indicators of the environment's health.

And in both studies, they are asking for records of public wildlife sightings, with details like time and location.

Singapore's waters harbour four species of dolphin or porpoise, and one type of sea cow, the dugong. Now and then, these are seen by boaters, divers and researchers, and from time to time a dead dolphin washes up on the island's shores.

Biologist Elizabeth Taylor of NUS' Tropical Marine Science Institute wants to find out if local waters are part of these marine mammals' migratory routes.

'If this is an important stop on the route, if we stop seeing dolphins here altogether, it might be an indicator that something is happening, such as more widespread climate or environmental change,' she said.

Her team's three-year study is known as the Singapore Wild Marine Mammal Survey, or Swimms.

The birds of prey that NSS members Yong Ding Li and Tan Kok Hui are studying are also indicator species.

Because they are at the top of the food chain, any environmental pollutants in their food accumulate in their bodies and show effects most severely.

But the grey-headed fish-eagle and the changeable hawk eagle seem to be thriving here, said Mr Yong, a junior college lecturer, perhaps because they can adapt to live on degraded land - land affected by human activity.

And Singapore's reservoirs mimic the fish-eagle's natural habitat near large rivers. In fact, the grey-headed fish-eagle is listed as 'critically endangered' as a precautionary measure - but that conservation status may have to be changed if it is seen more often and in greater numbers.

About three-quarters of sightings so far have come from the local bird-watching community, and Mr Yong and Mr Tan will be collecting data until July - to span the nesting season.

Likewise, the Swimms team is asking for dolphin and dugong sightings from boaters, ferry captains and even the Coast Guard. 'They're out on the water all the time,' Dr Taylor said.

The team is also training researchers who are based on St John's Island, and who make the journey from the mainland nearly every day.

But sightings are just the first phase of Swimms. Eventually, Dr Taylor and her team aim to link up with other dolphin research in the region, such as studies of the rare Mekong river dolphin, and map out the animals' habitats and migration patterns in detail.

The researchers also aim to use underwater sound equipment to pick up the animals' squeaks and trills. They can find as many as 10 times more animals this way, rather than relying on sightings.

Their ambitious, three-year project is partly funded by the Wildlife Reserves Singapore's Conservation Fund.

Sightings and records have always been contributed by the nature community and the public, said NUS lecturer N. Sivasothi, who is not related to either project but frequently helps collect community records. But tools such as the Internet and digital cameras have made this process easier than ever.

'The question is what sort of data can we expect to recruit and how to make the process more productive,' he said.

When too many records stream in, the need to confirm and follow up on them can be overwhelming. And researchers must also share the end result with those who submit records, he added.

But getting the public to participate in such studies has payoffs - such as raising awareness, said NUS' Dr Taylor.

She said: 'If people don't know there are dolphins here, they're not going to want to conserve them.'

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