By JAMES WOODFORD

It is a cold grey morning in Twofold Bay near Eden and Professor David Booth and his doctoral student Jaime Sánchez-Cámara are hunting for dragons.

It is not the mythical, fire-breathing variety they want to find but a creature almost equally as marvellous – the cryptic and spectacular weedy seadragon.

Their boat comes to anchor only a couple of hundred metres from where mountains of woodchips, harvested from the state’s south east forests, are loaded onto ships bound for overseas paper mills.

The visibility is not great and the water is bracing but soon Booth, Professor of Marine Ecology at the University of Technology, Sydney and chief scientist with the Sydney Institute of Marine Science and his student begin their search.

To the average snorkeller weedy seadragons are invisible but within an hour Sánchez-Cámara has found 15.

“These ones all seem much smaller than the ones in Botany Bay,” says Sánchez-Cámara, whose studies are also funded by the Sydney Aquarium Conservation Foundation.

Weedy seadragons are found from just north of Sydney and around southern the Australian coastline. But until the last few years virtually nothing has been known of their ecology.

Sánchez-Cámara, who is based at the University of Barcelona, in Spain, began tagging the creatures in 2001 using a benign fluorescent dye that is injected into the fish and is invisible except under ultraviolet light.

It is a testament to the lure of the weedy seadragon that Jaime Sánchez-Cámara is prepared to travel from the other side of the world to study the dragons.

So far around 150 have been tagged in this way from sites including Botany Bay, Bondi and Twofold Bay at Eden. Some specimens have even been found in the vicinity of the proposed intake pipes for the desalination plant.

For the first time the scientists have been able to get some information on how long the seadragons live – up to six years. They have also confirmed that the weedy seadragons have a high home site fidelity to their little patch of reef. One specimen, however, in Botany Bay was found 1.3 kilometres from where it was first tagged.

“This year we are finding fewer seadragons at the Kurnell sites,” says Sánchez-Cámara. “Why? natural causes? Legal or illegal collecting? Years of low recruitment? One possibility may be that seadragons are moving to deeper waters. In North Bondi this year the seadragons we found were deeper than other years.”

Sánchez-Cámara and Booth are also curious about the differences in appearance between the weedy seadragons in different parts of the coast. Size and number of fins appear to differ in different locations but Booth and his student are not sure whether this is evidence of different sub-species or environmental factors.

The biggest questions of all, though, are: how many there are, exactly where all the populations are located and what is the best way to manage them.

“I would dearly love to have the funds to do a full survey of the coast,” Booth says. “At the moment I would describe their status as ‘data deficient’.”

One concern is that because they have small home ranges they may be vulnerable to disturbance and therefore candidates for protection in marine reserves.

“But just because they’re pretty, doesn’t mean they’re not tough,” Booth says.

First Published Sydney Morning Herald 5/5/08