August 13, 2009
LONDON (Reuters) - The unique wildlife of the Galapagos Islandsis under threat from disease-carrying mosquitoes arriving on board growing numbers of aircraft and tourist boats, researchers said on Wednesday.
Experts fear the spread of the southern house mosquito, or Culex quinquefasciatus, could have the same devastating effect in the Galapagos as in Hawaii during the late 19th century, when disease wiped out many indigenous birds.
The mosquito was first spotted in the Galapagos in the mid-1980s, but its presence then was considered a one-off.
Now research by British and Ecuadorean scientists has found the insects are, in fact, transported regularly by plane and are island-hopping on boats, spreading throughout the archipelago.
Genetic tests also confirm they are able to survive and breed once they arrive at their new home.
"More ships and more aircraft are coming to the Galapagos every year and the risk of something being introduced is growing all the time," said Leeds University researcher Simon Goodman.
"That we haven't already seen serious disease impacts in Galapagos is probably just a matter of luck." The southern house mosquito is a carrier of diseases including avian malaria, avian pox and West Nile fever.
It was brought to Hawaii in water barrels on whaling ships, leading to diseases that are blamed for wiping out many bird species. Only 19 out of 42 species and subspecies of honeycreeper now remain in Hawaii.
Goodman and colleagues, who published their findings in the Proceedings of the Royal Society, fear everything is in place for a similar wipe-out in the Galapagos, given the rapid growth in transport links with the mainland.
Tourism is a major source of income for the Galapagos and is growing by around 14 percent a year.
The government of Ecuador recently introduced a requirement for insecticide spraying on aircraft flying to the Galapagos, but the scientists said the scheme's effectiveness was not being monitored and the rules did not apply to cargo ships.
Mosquitoes are the latest in a string of invaders -- including rats, wild pigs, flies and invasive plants -- that have colonized the Pacific islands, located about 600 miles off South America's coast along the equator.
British naturalist Charles Darwin developed his theory of evolution in the 19th century after studying the islands' unique animal population.