Kirtland's Warbler - Range and Ecology

Range and Ecology

Their breeding range is in a very limited area in the north of the Lower Peninsula of Michigan. They then come to southern Ontario. In recent years, breeding pairs have been found in the Upper Peninsula of Michigan, Wisconsin, and Ontario likely due to the rapidly expanding population. Breeding habitat is typically large areas (> 160 acres) of dense young jack pine (Pinus banksiana). Kirtland's Warblers occur in greatest numbers in large areas that have been clearcut or where a large wildfire has occurred. The birds leave their breeding habitat between August and October and migrate to The Bahamas and nearby Turks and Caicos Islands; they return to Michigan to breed again in May. In their winter habitat, they have been found primarily in scrub habitat, feeding on wild sage, black torch, and snowberry.

Kirtland's Warblers forage in the lower parts of trees, sometimes hovering or searching on the ground. These birds eat insects and some berries, also eating fruit in winter. For breeding they require stands of young (4 to 20 year old, 2–4 m high) Jack Pine trees. They nest on the ground. Their nest is usually at the base of a tree, next to a down log or other structure, and is well concealed by sedge, grasses, blueberries and other ground vegetation.