FWS Pacific Ocean

HabNet Coalition

Coastal Program Highlights

Saving an island ecosystem by eradicating invasive, acid-spitting ants

Johnston Atoll | 2012

Johnston Atoll National Wildlife Refuge, located in the central Pacific Ocean, is the only seabird nesting habitat in over 750,000 square miles of ocean. The refuge supports nesting for over 15 species of seabird and shorebirds, including one of the world’s largest populations of red-tailed tropicbird.

During a routine visit to the atoll, Refuge biologists discovered a super-colony of yellow crazy ants, covering approximately 70 acres. Swarms of these invasive, acid-spraying ants caused many birds to abandon their nests, including the red-tailed tropicbird. Although the atoll is closed to the public, it is believed that the ants were introduced by an illegal boat landing.

Working with the U.S. Geologic Survey, the Coastal Program and National Wildlife Refuge System developed and implemented an eradication plan. After 14 months, the eradication efforts reduced the ant population by over 95 percent, and the red-tailed tropicbird and other birds returned to their nests. Biologists continue to monitor and eradicate the ants to protect the world’s largest nesting colony of red-tailed tropicbird.

Read more about this project here. 

Cover Photo: Red-tailed tropicbird with chick, USFWS
Inset Photo: (Top) Crazy yellow ants infestation, USFWS | (Bottom) Crazy yellow ants, John Tann | Flickr