An uninhabited remote island near Antarctica is being overrun by mice after they were introduced to the area more than 200 years ago. Due to climate change, their breeding has become out of control and they have started to eat the seabirds in the special nature reserve.
Conservationists are now planning a mass extermination where helicopters will be dropping hundreds of tons of mice poison. To ensure success, they will be dropping it over the entirety of the island, which stretches over 115 square miles.
The island, a South African territory that’s part of the Port Edward Islands, is located in the southern Indian Ocean and is home to approximately 30 seabird species. For hundreds of years, the birds lived undisturbed. It wasn’t until the early 1800s that mice – the first mammal predators on the island – were introduced from seal hunter ships.
Since then, their numbers have gone up significantly, mainly due to the higher temperatures, which have turned the island into a warmer, more hospital habitat.
According to the Marion Mouse Extermination project manager, Dr. Anton Wolfaardt, the densities of mice have seen a massive increase as the rising temperatures have greatly lengthened their breeding season.
He noted that mice can reproduce when they’re as young as two months old and can have up to five litters every year, each with six to eight babies.
Currently, it’s estimated that there are over one million mice on the remote island and they’re feeding on seabirds – both adults and chicks – as well as invertebrates.
These mice have no problem feeding on birds several times their size. Conservationists have taken pictures of one of the rodents perched on the bloodied head of an albatross chick.
Mice typically don’t feed on seabirds; this phenomenon is only seen in a handful of islands across the world.
Since 2003, however, the number of mice feeding on seabirds on Marion Island has shot up alarmingly. What’s worse, is that the birds have not developed any defense mechanisms to protect themselves and will often stay still while the mice are eating away at them.
According to conservationists, nearly 20 seabird species will disappear from the island within 100 years if nothing is done.
That’s why they have come up with the eradication project to preserve the island’s ‘unique biodiversity’.
Wolfaardt said they will be using up to six helicopters to drop 550 tons of rodent poison across Marion Island. Pilots will be given exact routes and Wolfaardt’s team will be able to track where the rodenticide baits have dropped using GPS.
The bait that they’ll be using will not affect the island’s water sources or soil. It will not be harmful to the seabirds either, who feed on fish from the sea. While some other animals may be affected, they are expected to recover.
The eradication project is a collaboration between the National Department of Forestry, Fisheries, and the Environment, and BirdLife South Africa.
The project will cost $25 million, some of which will be provided by the South African government, and will likely proceed in 2027. Currently, they still neet to get regulatory approvals from various authorities.
