As Earth Day approaches, Island Conservation will share stories of hope and success in conservation.

Palmyra Atoll sees a 5000% increase in native trees recruitment, proving the far-reaching impacts of conservation.

The magnificent and unique Palmyra Atoll forms part of the Line Islands Archipelago, lying some 1,000 miles southwest of Hawai’i in the Central Pacific Ocean.

It has one of the best remaining examples of a tropical coastal strand forest found in the Pacific and one of the last predator-dominated marine ecosystems in the world. Many nationally and internationally Threatened, Endangered, and depleted species thrive there. The Atoll also supports ten nesting seabird species, including one of the largest Red-footed Booby colonies in the world, and the largest Black Noddy colony in the Central Pacific.

And it is these seabirds that had been most affected by the non-native black rats.

The Challenge

The rats were severely affecting seabirds, preying on both ground-nesting and tree-nesting birds, particularly Sooty and White Terns, eating eggs and chicks.

But it wasn’t only the birds that were impacted—it was also the native crabs and plant populations. Invasive rats had been attacking and consuming land crabs and eating precious seeds and seedlings of native trees, limiting native tree recruitment.

It was clear that the rats had to be removed if the atoll was to be preserved and the endemic species saved from extinction.

The Solution

During 2011, in direct response to this threat, the US Fish and Wildlife Service, The Nature Conservancy, and Island Conservation worked together to remove the invasive rats from Palmyra

Outcome

In the absence of invasive species, Island Conservation’s Conservation Science Program Manager, Coral Wolf, and a team of scientists have documented a 5000% increase in native trees, an abundance of crabs, and an increase in seabirds.

Removing the rats has allowed seabirds to flourish, and the rebounding native forest now provides the birds with important nesting and roosting habitat. When seabirds perch in the trees, they provide nutrients to the soil below through guano droppings. These nutrients are then taken up by native plants and also wash into the ocean where they benefit the surrounding reefs.

Featured photo: A Red-footed Booby perched in a tree on Palmyra Atoll. Credit: Andrew Wright