Temperate Breeders

Temperate Breeders of High Tri-National Concern

• 24 species breeding primarily in the United States and Canada

• 67% have special protection by at least one nation’s endangered species laws, but only three species are protected throughout their entire range

• 71% are migratory

This group includes temperate-zone species with moderate or large breeding distributions in the United States and Canada. PIF identified these species as high priorities in the 2004 Landbird Conservation Plan, and they all continue to warrant immediate tri-national conservation action to prevent further declines (for details, see Appendix B).

Temperate Breeders of High Tri-National Concern

Overlay of breeding (top), in-transit (center), and winter (bottom) ranges of temperate-zone breeders of high tri-national concern.

Collectively, the breeding ranges of these species cover most of the United States and Canada, and three species (Spotted Owl, Black Swift, and Olive-sided Flycatcher) have breeding populations in all three countries. More than 70% are migratory, most with populations wintering in or passing through Mexico; all but four species depend on habitats in at least two of our countries.

Black Swift (left), Cerulean Warbler (center), and Canada Warbler (right) are among the 24 temperate-breeding species of high tri-national concern.

Photos (L-R) by Glen Tepke, Greg Lavaty, Gerry Dewaghe

These high-concern species breed in all major temperatezone habitats (see Appendix B), but nearly half are primarily associated with either grasslands or temperate eastern forests. Cerulean Warbler requires large tracts of mature deciduous forest for breeding, whereas Golden-winged Warbler requires disturbed or early successional forests in the same regions. Both of these warblers, along with boreal forest breeders such as Olive-sided Flycatcher and Canada Warbler, winter in tropical highland forests of Central and northern South America.

High-concern grassland birds include migrants, such as Sprague’s Pipit, Baird’s Sparrow, and Chestnut-collared Longspur, that winter primarily in northern Mexico, as well as resident Greater and Lesser prairie-chickens. Both Black-capped and Bell’s vireos breed in aridland habitats of the southwestern United States and winter in tropical deciduous forests of Mexico. Other species highlight the need to conserve sagebrush (Greater Sage-Grouse), pinyon-juniper woodland (Pinyon Jay), old-growth coniferous forest (Spotted Owl), and Sonoran desert scrub (Bendire’s Thrasher) in the western United States.

(L-R) These species demonstrate the need to conserve important temperate habitats: Greater Sage-Grouse (sagebrush); Black-capped Vireo (aridlands); Pinyon Jay (pinyon-juniper woodlands); Bendire's Thrasher (Sonoran desert scrub); and Baird's Sparrow (mixed and shortgrass prairie).

Photos (L-R) by Ram Papish, Chris Tessaglia-Hymes, James Livaudais, Gerry Dewaghe, David Cree

Because these high-concern species occur in every major habitat, they face a diversity of threats from land-use policies and practices in Canada and the United States for agriculture, livestock grazing, ecosystem modification, contaminants and exotic species, urbanization, energy development, and logging (see Appendix B). Agricultural practices in particular affect not only specialized grassland birds, but also migratory species that winter in the same tropical forest habitats as high-concern resident species. More than 40% of these species are predicted to be adversely affected by climate change, due to a range of factors such as loss of alpine tundra (Black Rosy-Finch) and high-elevation forests (Bicknell’s Thrush), increased drought in grassland habitats, drying of ephemeral waterfalls (Black Swift), and loss of coastal habitats as sea levels rise (White-crowned Pigeon).

Migratory species also face high threats on their wintering grounds, especially loss of grasslands in northern Mexico and threats to tropical forests in southern Mexico and elsewhere in Latin America and the Caribbean.