Albatrosses are one of the most important seabird populations in the world. In order to try to protect them, officials have decided to get rid of mice on Marion Island, a remote South African territory that is located about 1,250 miles southeast of Cape Town.
Mice are overpopulating the island, and they have begun to prey on the eggs of albatrosses and other seabirds. They have even been found to attack birds. As a result, the island’s ecosystem is at risk.
“The densities of mice have literally increased by about 500 percent over the last 30 years,” said Anton Wolfaardt, the project manager of the Mouse-Free Marion project.
“The seabirds have no evolutionary defense mechanism against this novel predator. And so they literally just sit on their nests while night after night the mice nibble away at them, eventually causing them to become fatigued and die for a variety of reasons.”
Due to climate change, Marion Island has been experiencing warmer temperatures, allowing the mice to breed more often. Humans introduced them to the island in the early 1800s. Since then, their numbers have become overwhelming.
The wandering albatross, also known as the snowy albatross, is just one of the island’s bird residents. It has the largest wingspan of any bird in the world, reaching 11.5 feet. Their conservation status is listed as vulnerable. About a quarter of the species’ population nests on Marion Island, so it is critical that more conservation efforts are made.
At a meeting held by BirdLife South Africa, evidence of birds with severe injuries was presented. Some of the birds had flesh eaten away from their heads. According to the Mouse-Free Marion Project, the mouse attacks could lead to the extinction of 19 out of 29 seabird species that breed on the island.
The South African Department of Environment, Forestry and Fisheries and BirdLife South Africa plan to use helicopters to drop 600 tons of pellets laced with pesticides all over the island. The project is estimated to cost around $29 million, but so far, only a quarter of the money has been raised.
Dropping poison on the island comes with great risk. The birds may eat the poisoned mice, causing harm to themselves. Still, Wolfaardt believes the ecological benefits will be worth it, and certain measures have been taken to reduce unfavorable consequences.
Rich Lindie – stock.adobe.com – illustrative purposes only, not the actual albatross
For example, the toxin will not be water-soluble, so it will not contaminate the water sources on the island. In addition, the operation is planned to take place in the winter. During this time, mice are at their most vulnerable, and many seabirds have left the island.
“Based on experience of previous operations, we know that the majority of mice—perhaps 80 to 90 percent—will die underground in their burrows, where they are obviously less accessible to scavenging birds,” said Wolfaardt.
However, conducting the mission in winter poses significant challenges, particularly regarding weather. Poor visibility and strong winds can throw a wrench into the plan.
The project is expected to begin in 2027. It will take between four to six months to complete. Advanced GPS technology and skilled helicopter pilots will be employed for the task.
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