Tourism and urbanization are leading to a massive loss of insects on tropical islands, a study of the Maldives has discovered.
On the islands with progressive urbanization, researchers from the University of Bayreuth in Germany documented on average 48 per cent fewer insect species than on uninhabited islands, and on tourist islands even 66 per cent fewer insect species.
“Habitat fragmentation and a reduction in vegetation density are having significant effects on biodiversity on urban islands,” the study said.
The findings were published in the Open Science journal of the British Royal Society.
Oceanic islands make up only slightly more than two per cent of the Earth’s land mass. However, they are home to around 20 per cent of all known animal and plant species, and around half of all endangered species.
“Human-induced global species extinction is particularly drastic on oceanic islands in the tropics,” study’s lead author Sebastian Steibl was quoted as saying in a statement from the University of Bayreuth.
In the Maldives, three types of islands, located close to each other, were clearly distinguished from one another by researchers: uninhabited islands, islands inhabited by the local population and islands used for tourism.
“On islands used for tourism, it is probably the use of pesticides that mainly causes the drastic decline in insect diversity,” Streibl said, adding that, although the pesticides are used against mosquitoes, other species are also affected.
According to the researchers, the long-term consequences of the insect mortality on the islands must now be clarified by further studies.