A Review of the Rat Island Seabird Habitat Restoration Available

For the last 230 years, introduced Norway rats have been present on Rat Island in the central Aleutian Islands. The rats, introduced by a shipwreck in 1780, have killed untold thousands of birds attempting to nest on Rat Island, all but extirpating birds from the island. In 2008, the U.S. Fish and Wildlife Service, Island Conservation, and The Nature Conservancy successfully removed the introduced predators using standard methods tested hundreds of times around the world. Now, with the island rat-free for the first time in over two centuries, the ecosystem is beginning to recover: birds are again nesting on the island, including some species that were not observed on Rat Island when the rats were present. However, despite the best efforts of everyone involved to remove the rats with the least risk, a higher-than-expected number of gulls and eagles also died after the bait application.

The partners of the Rat Island Habitat Restoration Project commissioned an independent review of the restoration project to understand what caused the bird mortalities, and how best to avoid those impacts in future eradications in the Aleutians. This review by the non-profit Ornithological Council is available to the public. The review identifies some issues that may have contributed to the deaths of the non-target species, we have taken the opportunity to learn from these findings to ensure that future projects to restore island habitats can be undertaken with minimum risk to native species while still achieving the conservation success seen on Rat Island and on hundreds of other islands around the world.

The partners in the Rat Island Habitat Restoration Project strive to restore island habitats while minimizing potential harm to non-target species. We are committed to using each project as an opportunity to learn and improve the safety and effectiveness of our conservation actions.

This 85-page review was prepared by the non-profit Ornithological Council.