Cats Should Be Killed to Save Earth's Most Endangered Species From Extinction, Scientists Say
Animals such as feral cats and dogs should be culled from islands around the world to save their prey from extinction, according to conservationists.
Eradicating creatures like rats, mongooses, pigs, and goats from 169 islands could save some 9.4 percent of the planet's most-threatened animals, argue the authors of a study published in the journal PLOS One.
The world's 465,000 islands only take up around 5.3 percent of land on Earth, yet they are home to 75 percent of known extinctions of bird, mammal, amphibian and reptile extinctions since 1500, the authors highlighted. Now, 36 percent of the world's critically endangered species live on these pieces of land.
To arrive at their conclusion, the researchers looked at data on 1,184 highly threatened native vertebrates, as identified as critically endangered or endangered on the IUCN Red List, and 184 non-native mammals that live on 1,279 islands across the world.
Using this data, they created a list of 292 islands whose native animals would benefit from culling invasive mammals. Of these islands, the researchers highlighted 107 across 34 countries where eradication could start as soon as 2020.
Socorro in Mexico was ranked as the island in most need of restoration, where the cats and mice could be culled to save the mocking bird, the Urosaurus auriculatus species of reptile and the Townsend's shearwater bird.
The eradication of dogs, goats, and cats, on San Jose, Mexico, could meanwhile save the kangaroo rat and the brush rabbit, which are unique to the island.
And on Gough in St Helena, a British Overseas Territory. mice would be killed to save the Gough finch, Tristan albatross, sooty albatross, Atlantic yellow-nosed albatross and Atlantic petrel. A separate study published last year in The International Journal of Avian Science found huge mice were ravaging seabird populations on the island in the South Atlantic.
Commenting on the mouse problem on Gough last year, study author Anthony Caravaggi of the University College Cork, Ireland, told Newsweek how a cull would work. "A toxic cereal pellet will be dropped from helicopters during the winter when fewer seabirds breed on the island. There are no other mammal species on Gough to eat the pellets.
"This is the same technique that has been successfully used to eradicate rodents on many islands worldwide," he said.
The authors wrote culls would "make a major contribution towards achieving global conservation targets adopted by the world's nations."
Dr. Nick Holmes, lead author of the study from the group Island Conservation, commented: "Eradicating invasive mammals from islands is a powerful way to remove a key threat to island species and prevent extinctions and conserve biodiversity."
"This study is an invaluable global assessment of where these future conservation opportunities exist and supports regional and national decision-making about where and how to prevent extinctions."
Stuart Butchart, chief scientist at the conservation group Birdlife International, told BBC News eradicating the animals could save "extraordinary species that have evolved in isolation and are only found on these remote islands".
Past research by Island Conservation found rats on the French Polynesia atoll of Tetiaroa were threatening sea turtles by eating their eggs.
