Bird Database

Bicknell’s Thrush

(Catharus bicknelli)

State of the Birds
At a Glance

Habitat

Migration

Mid-distance

Population

Decreasing

Threats

Habitat loss and fragmentation, Habitat maturation, Climate change, Pollution

Conservation Actions

Protect critical winter habitat, Minimize impacts to breeding habitat

Bicknell’s Thrush

(Catharus bicknelli)

Bicknell’s Thrush is the flagship bird species for high elevation conifer forest in the northeastern United States and southeastern Canada, breeding only above 2500’ from the Catskills of New York to southern Quebec and Nova Scotia. It spends the winter in forested parts of the Greater Antilles, almost entirely on the Island of Hispaniola (home of Haiti and the Dominican Republic). Populations of this regional endemic have been in gradual decline for decades, and over that time it has disappeared as a nesting species from isolated mountaintops along the southern edge of its range, including iconic peaks like Greylock in western Massachusetts and Monadnock in southwestern New Hampshire.

Here in the breeding range, the dense spruce-fir habitat preferred by Bicknell’s Thrush is largely intact. Development associated with ski areas and wind turbines is the most common source of direct habitat loss but is relatively rare since most habitat is protected in state parts and national forests. More insidious threats take the form of acid rain and climate change, which cause subtle changes to habitat quality that can take years to become apparent. Climate change is of particular concern, because some models predict that high-elevation conifer forest will shift upslope as the region warms, resulting in a reduced total area in which thrushes can nest.

Habitat loss in the winter range is a much higher concern. Haiti and the Dominican Republic have lost 90% and 50% of their original forest and much of what remains is still at risk. Because these are poor countries, local people exert immense pressures on natural resources just to feed their families and make a living, and even protected areas aren’t always safe. Enforcement of reserve boundaries, combined with economic policies to lift people out of poverty, are key conservation actions to ensure the continued survival of Bicknell’s Thrush, thus providing one of the clearest examples of why biologists need to consider the full annual cycle of migratory species when trying to conserve them.

Seasonal Abundance

Relative abundance based on eBird data. Numbers indicate likelihood of finding this species in suitable habitat at a given time of year, not actual numbers encountered.

Bicknell’s Thrush
Range Map

Information for the species profiles on this website was compiled from a combination of the sources listed below.

  • The Birds of New Hampshire. By Allan R. Keith and Robert B. Fox. 2013. Memoirs of the Nuttall Ornithological club No. 19.

  • Atlas of the Breeding Birds of New Hampshire. Carol R. Foss, ed. 1994. Arcadia Publishing Company and Audubon Society of New Hampshire

  • Birds of the World. Various authors and dates. Cornell Laboratory of Ornithology.

  • Data from the Breeding Bird Survey

  • Data from the Christmas Bird Count