Action timeline

1984 – The U.S. Fish and Wildlife Service designated the Thorne’s hairstreak butterfly as a Category 2 candidate for listing under the Endangered Species Act.

June 4, 1991 – The San Diego Biodiversity Project petitioned the Service to list the Thorne’s hairstreak and Hermes copper butterflies as endangered.

July 19, 1993 – The Service rejected the 1991 petition to list the Thorne’s hairstreak on a technicality, alleging that it lacked necessary information (while simultaneously admitting to already possessing this same information). While the Service promised to conduct a status review of the species, there is no evidence that it did so.

July 19, 1995 – The Thorne’s hairstreak’s Category 2 candidate status was removed when the Service unilaterally abolished the Category 2 candidates list.

October 25, 2004 – The Center submitted a petition to list the Thorne’s hairstreak and Hermes copper under the Endangered Species Act.

October 18, 2005 – The Center filed suit against the Service for failing to respond to conservation groups’ two petitions to list the Thorne’s hairstreak and Hermes copper butterflies.

August 8, 2006 – Despite the fact that the Thorne’s hairstreak butterfly had been devastated by fire and other threats that still posed a significant danger to the butterfly, the Service announced in its 90-day finding that it would not list the species under the Endangered Species Act.