May 6, 1991 – The U.S. Fish and Wildlife Service received a petition from the International Council for Bird Preservation to put the medium tree finch on the federal endangered species list.
December 16, 1991 – The Service made a positive 90-day finding on the May petition.
March 28, 1994 – The Service published a 12-month finding on the 1991 petition, determining that the medium tree finch warranted protection but that its listing was precluded by other listing priorities.
January 23, 2008 – As a result of a lawsuit brought by the Center, the U.S. District Court for the Northern District of California found the Fish and Wildlife Service in violation of the Endangered Species Act in its failure to move forward in protecting the medium tree finch. The court ordered the Service to propose a listing rule for the bird by the end of 2008.
July 29, 2008 – The Service published a notice announcing its annual petition findings for foreign species, announcing that listing was warranted for the medium tree finch.
December 8, 2008 – The U.S. Fish and Wildlife Service proposed to list the medium tree finch as an endangered species under the federal Endangered Species Act.
July 27, 2010 ? The Service listed the medium tree finch as an endangered species.