QUITO — The Associated Press
Published Thursday, Nov. 15 2012, 8:47 AM EST
The unique bird and reptile species that make the
Galapagos Islands a treasure for scientists and tourists must be preserved,
Ecuadorean authorities say – and that means the rats must die, millions of
them. A helicopter is to begin dropping nearly 22 tons of
specially designed poison bait on an island Thursday, launching the second
phase of a campaign to clear out by 2020 non-native rodents from the
archipelago that helped inspire Charles Darwin’s theory of evolution.
The invasive Norway and black rats, introduced by whalers
and buccaneers beginning in the 17th century, feed on the eggs and hatchlings
of the islands’ native species, which include giant tortoises, lava lizards,
snakes, hawks and iguanas. Rats also have depleted plants on which native
species feed.
The rats have critically endangered bird species on the
19-island cluster 1,000 kilometres from Ecuador’s coast.
“It’s one of the worst problems the Galapagos have.
(Rats) reproduce every three months and eat everything,” said Juan Carlos
Gonzalez, a specialist with the Nature Conservancy involved in the Phase II
eradication operation on Pinzon Island and the islet of Plaza Sur.
Phase I of the anti-rat campaign began in January, 2011,
on Rabida island and about a dozen islets, which like Pinzon and Plaza Sur are
also uninhabited by humans.
The goal is to kill off all non-native rodents, beginning
with the Galapagos’ smaller islands, without endangering other wildlife. The
islands where humans reside, Isabela and Santa Cruz, will come last.
Previous efforts to eradicate invasive species have
removed goats, cats, burros and pigs from various islands.
Pinzon is about 1,812 hectares in area, while Plaza Sur encompasses
just 9.6 hectares.
“This is a very expensive but totally necessary war,”
said Mr. Gonzalez.
The director of conservation for the Galapagos National
Park Service, Danny Rueda, called the raticide the largest ever in South
America.
The poisoned bait, developed by Bell Laboratories in the
United States, is contained in light blue cubes that attract rats but are
repulsive to other inhabitants of the islands. The one-centimetre-square cubes
disintegrate in a week or so.
Park official Cristian Sevilla said the poison will be
dropped on Pinzon and Plaza Sur through the end of November.
A total of 34 hawks from Pinzon were trapped in order to
protect them from eating rodents that consume the poison, Sevilla said. They
are to be released in early January.
On Plaza Sur, 40 iguanas were also captured temporarily
for their own protection.
Asked whether a large number of decomposing rats would
create an environmental problem, Mr. Rueda said the poison was specially
engineered with a strong anti-coagulant that will make the rats dry up and
disintegrate in less than eight days without a stench.
It will help that the average temperature of the islands
is 24 degrees Celsius, he added.
The current $1.8-million phase of the project is financed
by the national park and non-profit conservation groups including Island
Conservation.
The Galapagos were declared protected as a UNESCO Natural
Heritage site in 1978. In 2007, UNESCO declared them at risk due to harm from
invasive species, tourism and immigration.
