Disease-carrying mosquitoes from tourist planes landing to the Galapagos could be a threat to the biodiversity on these islands. Arnaud Battaile from Leeds University and his colleagues report in the Proceedings of the Royal Society B that the southern house mosquito, Culex quinquefasciatus is being constantly introduced to the island via tourist planes. Scientists had previously thought that this mosquito was introduced to the islands only once, in the 1980s (see press release).

The southern house mosquito has a dark history of infecting pristine island environments, carrying various diseases such as avian malaria, avian pox and West Nile fever. When it was introduced to Hawaii in the late 19th century, it is thought to have caused extinction of many endemic bird species..

The unique fauna of the Galapagos islands played an important role in Charles Darwin’s Beagle journey. Because of its isolated position 600 miles away from the mainland it has escaped many of the diseases present in South America and as a result Galapagos animals are susceptible because they have built up no resistance through exposure, Simon Goodman, a co-author of the paper told the Daily Telegraph. “You only need a single infectious mosquito to initiate a disease cycle,” Goodman says.

The team found about one mosquito in every 10 planes arriving at the Galapagos between October 2006 and September 2007. The mosquitoes that arrived on planes can survive and breed on islands, and can also island-hop by hitching a ride on boats. Although none of the mosquitoes captured on the planes in this study carried dangerous viruses, it is possible that they could bring viruses such as the West Nile Virus from the mainland that could spread across the archipelago’s 200 or so islands by these hitchhikers. “West Nile virus also affects reptiles and mammals, and so could impact other iconic Galapagos species such as marine iguanas and sea lions," Goodman told New Scientist.

Posted on behalf of Mico Tatalovic