Top 20 Most Threatened Bird Habitats in the U.S. - American Bird ...

with change. An antpitta deprived of humid forestconditions in the small swath of the Andes in which itevolved has little chance of survival.Photo: FWSSo, as we humans continue to convert habitat toconditions that superficially seem to be of greatershort-term benefit to us, we split the bird world intothose that thrive with new opportunities and thosethat wither in the face of change. Bird conservationis simply an attempt to provide for the needs of thatever-increasing latter group.The kind of change that we call habitat loss is conversionof habitat conditions required by specialized birdspecies to conditions in which those birds cannotsurvive. This is the fundamental cause of populationdeclines in birds.But not all change is bad. Fire, flood, extreme weather,disease, and urban sprawl may benefit some birds.Clear-cutting of forests and overgrazing of grasslandswork nicely for others. The worst types of change areconversion to agriculture, which tends to be at leastpartially reversible, and conversion to urban conditions,which tends to be permanent.To select the 20 most threatened bird habitats,we considered the severity of historic habitat loss,current threats to remaining habitat, past andongoing restoration efforts, and the existenceof protected areas such as parks, grasslands,wildlife refuges, and reserves. ABC’s Green List(www.abcbirds.org/greenlist.htm) was used togauge the value of habitat for conservation priorityspecies. The number of Green List species (whichincludes birds listed under the Endangered SpeciesAct) found in high concentrations weighted theimportance of the habitat for birds.Acorn Woodpeckers: Glen Tepke; TOP ROW: Lawrence's Goldfinch: Glen Tepke; Blue Grouse (recently split into Dusky Grouse and Sooty Grouse): USDA Forest Service;BOTTOM ROW: Burrowing Owl; Black Skimmers: Glen Tepke; Tricolored Heron: Bill Hubick; Western Bluebird: Ashok KhoslaPage 6 of 48