Science and technology Conservation
How to prepare poached eggs A tracking device may help stop the robbery of turtles'
nests. Turtles have a problem. They are delicious. And so are their eggs. That has led
to heavy hunting in the past. These days, though, the seven species of marine turtle
are protected in most countries. If turtle soup is legally on the menu its source will
be a freshwater species such as the North American snapping turtle. But that does
not stop the eggs of marine turtles being poached. Which they are, frequently. Such
poaching is often ignored by local bobbies. But even if the authorities do wish to
clamp down on it, arresting the small-fry who dig the eggs up on beaches where turtles
nest will not deal with the problem. That requires finding the trade's organisers.
And this can be hard. To assist the process Kim WilliamsGuillén of Paso Pacifico,
an American conservation charity, and Helen Pheasey of the University of Kent, in
Britain, have come up with a nifty gadget. It is a global positioning system
transmitter enclosed in a plastic shell made by 3D printing. The result looks like
a turtle's egg and weighs about the same. Dug up and carried away by poachers, it can
lead the police to those poachers' bases of operation. As they report this week in
Current Biology, Dr Williams-Guillén and Dr Pheasey have now tested their invention
in Costa Rica, a place where turtle-egg poaching is rife. They set the printer to mimic
the eggs of two species, the green and the olive ridley, which frequent that country's
coast-lines, and placed a decoy egg into each of 101 turtle nests on four beaches
where poaching is a problem. The decoys were rigged to remain dormant until their
shells were exposed to the air. At that moment-presumed to signal the arrival of
poachers-the "egg" in question starts broadcasting its location once an hour. In all,
25 of the decoys were poached. They told different stories. Some travelled just a few kilometres,
with one ending up at a bar 2km away from the nest it was taken from, where its signal abruptly
ended. Others went quite a distance. One, for example, was carried 137km inland, to a
supermarket loading bay, before transmitting its final signal from a residential property nearby.
The most curious tale, though, was told by a decoy that ended up in Cariari, a town 43km from the
beach where it had been deployed. To their surprise, the researchers were sent photographs of this
particular device by members of a local turtle-monitoring project. This group had been contacted
by the egg's purchaser, who was happy to volunteer where he had bought it indicating either that
he did not understand that the trade was illegal, or that he didn't care. To make sure that they,
themselves, were not harming what they were intending to protect, the researchers monitored all
of the decoy-laden nests which had survived the attentions of poachers and compared these
nests' outputs of hatchlings with those of 44 other surviving nests that had no decoy in them. Both
sorts of nest had the same hatching rates, suggesting that adding a decoy did not affect the
development of the eggs it was hidden among. Given the success of their project, Dr
Williams-Guillén and Dr Pheasey propose that the idea should be used more widely for
turtles.They also suggest that similar decoys might help protect the eggs of other endangered
reptiles-and birds-that are collected and traded illegally.