August 12, 2009

Mosquitoes A Threat To The Galapagos Islands

Disease carrying mosquitoes that are being carried over with tourists are posing a great threat to the unique wildlife of the Galapagos Islands, researchers said on Wednesday.

Experts have reason to fear that the spread of the southern house mosquito (Culex quinquefasciatus) could have the same devastating impact on the ecology of the Galapagos as it did in Hawaii during the late 19th century, when disease killed off many indigenous birds.

First noticed in the Galapagos in the mid-1980s, the pesky mosquitoes' presence was thought to be a one time occurrence.

However, research by British and Ecuadorian scientists has now found that the insects are actually being brought over regularly by plane and are then traveling from island to island, having a potentially lethal effect on all of the archipelago.

"Few tourists realize the irony that their trip to Galapagos may actually increase the risk of an ecological disaster," said Simon Goodman of Leeds University, one of the study's co-authors.

Arnaud Bataille, another researcher on the eight-page study, said "On average the number of mosquitoes per airplane is low, but many aircraft arrive each day from the mainland in order to service the tourist industry."

What is worse is that genetic tests have also confirmed that the mosquitoes have the ability to survive and continue breeding in 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 Goodman.

"That we haven't already seen serious disease impacts in Galapagos is probably just a matter of luck," he added.

The southern house mosquito carries a range of diseases, including avian malaria, avian pox and West Nile fever.

The parasite was first brought to Hawaii in water barrels on whaling ships, which led to diseases that likely caused the many species of birds to be completely wiped out. Now, only 19 of the 42 species and subspecies of honeycreeper can be found in Hawaii.

Goodman and colleagues are afraid that it is now the perfect storm for the same type of wipe-out in the Galapagos, considering the quick growth of transport links with the mainland.

Tourism has been a major source of income for the Galapagos for a while, and it is growing by around 14 percent a year.

The Ecuadorian government recently began requiring insecticide spray on aircrafts flying to the Galapagos, but the scientists said there is no way to gauge the effectiveness of the plan, and there are no such requirements for cargo ships.

There has been a slew of other uninvited pests, such as rats, wild pigs, flies and invasive plants that have colonized the Pacific islands, but mosquitoes are the most recent addition to the list.

The British naturalist Charles Darwin developed his theory of evolution in the 19th century after studying the unique animal population of the Galapagos islands


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