Team flocks to collect dead birds for research

Feng Zengkun The Straits Times 26 Nov 2013;

Have you spotted a dead bird? Then undergraduate David Tan is your man.

The 24-year-old promises to "drop everything and rush down" to collect the carcass.

The self-proclaimed snatcher of dead birds explained in a widely shared Facebook post earlier this month why he is a bag man for science.

His work is part of a wide-ranging new effort here to understand bird evolution, conservation and disease, and how this relates to and impacts humans.

And no bird is too common for the cause.

"While mynahs and sparrows might seem common and worthless", future research projects may require DNA extracts from their carcasses, he said.

He is part of the Avian Genetics Laboratory at the National University of Singapore (NUS). Set up in January, it aims to build up a repository of winged creatures' genetic material to better understand their evolution and ecology.

The lab's freezer is full of local species such as the Japanese sparrowhawk and red-legged crake, and the researchers have so far amassed records of more than 50 species.

The lab's head, Assistant Professor Frank Rheindt, said the data could be used to identify species in danger of extinction due to poorer genetic diversity, which could help guide conservation efforts.

Dr Rheindt, who is with the university's Department of Biological Sciences, said a large part of the lab's analyses has become feasible only in recent years due to technological advances that allow genes to be sequenced faster and more cheaply.

The 36-year-old has been studying birds for more than a decade, including at Harvard University before he came to NUS.

"When I finished my PhD at the University of Melbourne in Australia in 2008, I had worked for five years on two genes for 80 birds," he said. That is about one-millionth of a bird genome.

"With enough funding, my students could now do whole genomes in one afternoon."

Remarkably, the team is doing its work without sacrificing a single live bird.

The team collects flesh samples from the dead birds and gets blood from live birds in the field through a tiny prick on the underside of a wing.

Dr Rheindt told The Sunday Times that the impact of human activity on nature can be tracked by studying samples of the same bird species across time.

The researchers also study dead and living birds across the region to find out how they may have evolved, and to better understand their travel and mating patterns.

In Singapore, examining the same species across green pockets allows them to gauge how successful eco-links are - and which birds are on an extinction clock.

Dr Rheindt explained that the country's rapid development after the Japanese Occupation led to fragmented habitats. Trapped in small spaces, some birds may have bred within their own families.

"It's extinction with a time lag. It takes a few decades for everyone in the little patch to become cousins." Once that happens, the genetic defects start to pile up as the in-breeding continues, until the offspring are either stillborn or have disabilities and die soon after birth.

This may explain why some species such as the white-bellied woodpecker, which has not been seen for almost a decade, may have become extinct here, he said.
"We call some species 'the living dead'. They may be alive but they are functionally dead because their offspring will become unviable."

Another reason to make sure the birds have high genetic diversity is to protect people.

"A healthy biodiversity could mean that fewer birds are susceptible to the same disease, which could lessen the risk of the disease jumping over to humans," he said.

The lab's partners at the Duke-NUS Graduate Medical School are researching this issue. The Avian Genetics Laboratory's work for the school follows strict safety guidelines and is done in coordination with the Agri-Food and Veterinary Authority and the National Parks Board.

He added that bird flu has been around for a long time, even though recent chicken-rearing practices for the meat and egg trade may be increasing the instances of it crossing over to people.

Call Mr Tan on 9176-8971 if you spot a dead bird.