A group of Western-state governors has released a report on voluntary efforts in 11 states to conserve the habitat of sage grouse as part of an effort to avoid a federal listing of the bird under the Endangered Species Act.

The 32-page "2014 Sage-Grouse Inventory" released Thursday by the Western Governors' Association identifies conservation work during the year and is accompanied by a 101-page appendix listing efforts since 2011.

The U.S. Fish and Wildlife Service has a deadline of Sept. 30 to decide whether to propose the greater sage grouse as needing protections that could limit ranching as well as oil and gas drilling.

The association says a listing will reduce voluntary conservation work and hurt states' economies.

The chicken-sized bird once numbered in the millions, but the population is now below 500,000.