A species that only exists on the Galapagos: the Drusenkopf. Image: Haplochromis, Wikipedia
Reading Trapped insects threaten the biodiversity of the Galapagos Islands, where even Darwin observed his famous finches: With the increasing tourism, more and more mosquitoes are unintentionally introduced into aircraft holds and spread unchecked on the islands. Since native wildlife is not adapted to the mosquito-borne diseases, many species are likely to be killed in the future unless countermeasures are taken. The Galapagos Islands are part of Ecuador and are located about a thousand kilometers from the mainland in the Pacific. Its biodiversity inspired Charles Darwin in the 19th century of his theory of the evolution of species. Still, 95 percent of the original biodiversity is intact. So far, the archipelago has been largely spared from global environmental degradation. That's another reason why the archipelago is attracting more and more tourists, which could be a problem for native flora and fauna. Uninvited guests, such as the mosquito Culex quinquefasciatus whose propagation on the Galapagos has now been investigated, are also brought in with human visitors. The mosquito transmits various diseases that otherwise do not occur there and to which the animal world is therefore not adapted.

According to the study, for which aircraft were systematically examined and genetic tests carried out on mosquitoes, the pests are transported to the islands in the luggage compartments of aircraft, where they are released into the wild. They not only survive easily, but also integrate into existing populations of other insects and reproduce. They are also distributed by tourist boats among the islands of the archipelago. Especially the birdlife of Galapagos is endangered, as Culex quinquefasciatus carry among other things bird malaria, bird pox and the West Nile virus, which almost exclusively affect birds. The Galapagos Islands could therefore face the same fate as Hawaii, where the same insect was introduced in the late 19th century and wiped out 23 of 42 species of turquoise bird.

Study leader Arnaud Bataille explains the problem as follows: The number of insects, which are carried on average per aircraft, is not dramatic, but there are now so many aircraft landing, that the amount of mosquitoes just matter. Tourism is the most important source of income of the islands, which belong to the UN World Natural Heritage and whose flora and fauna since 2007 is classified as endangered. To make the livelihoods more ecologically sound, the Ecuadorian government decided to treat incoming aircraft with insecticides. According to Bataille, the effectiveness of this measure has not yet been proven and should also be extended to incoming ships. The government must enforce strict rules, because tourism is growing in any case.

Arnaud Bataille (University of Leeds) et al .: Proceedings of the Royal Society B, DOI: 10.1098 / rspb.2009.0998. ddp / science.de? Martina Bisculm advertisement

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