An US environmental group says it will sue the US Fish and Wildlife Service unless it takes immediate action to protect a small bird native to Tinian Island in the Northern Marianas.
The Centre for Biological Diversity says the Tinian Monarch is under threat from increasing US military training exercises on the island.
The centre wants the bird listed under the Endangered Species Act and says it has filed a formal notice of intent to sue.
One of the centre's scientists, Tara Easter, says the bird and its tiny island home need protection to have any chance of survival.
"New data has come out saying the bird is declining and there so many threats to its habitat right now because of increased military activities, as well as Tinian trying to boost its tourism industry, so this forested habitat that it relies on is really under threat."
Tara Easter says suing the US Fish and Wildlife Service is a last resort and she hopes it does not come to that.