The Kirtland’s Warbler, Dendroica kirtlandii, is a small songbird of the New World warbler family, named after Jared P. Kirtland, an Ohio doctor and amateur naturalist.
These birds have bluish-grey upper parts with dark streaks on the back and yellow underparts with streaked flanks. They have thin wing bars, dark legs and a broken white eye ring. Females and juveniles are browner on the back.
Like the Palm Warbler and Prairie Warbler, they wag their tails frequently. Their song is a loud chip-chip-chip-too-too-weet-weet often given from the top of a pine.
They require young, 4 to 20 year old Jack Pine trees for nesting. The nest is an open cup on sandy soil near one of the Jack Pines. Their breeding habitat is in a very limited area in the north of the Lower Peninsula of Michigan; they used to breed in Ontario but have not done so since the 1940’s.
They have still been observed to occur in Ontario and the Upper Peninsula of Michigan, and beginning in 2005, a small number have been observed in Wisconsin. In 2007, three Kirtland’s Warbler nests were discovered in central Wisconsin and one at CFB Petawawa, providing an auspicious sign that they are recovering and expanding territory.
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. In winter, they migrate to pine forests in the Bahamas.
The numbers and range of this bird have decreased since the early 20th century due to loss of suitable breeding habitat. Since Jack Pines only seed after significant disturbances, such as forest fires and clear cuts, this bird’s habitat is being preserved by controlled burns and staggered timber harvests in its limited breeding range.
Since this habitat management regime was begun in the 1970s, the birds numbers have steadily risen, though they are still at dangerously low levels. People have also intervened to protect this bird against nest parasitism by Brown-headed Cowbirds, to which these birds are highly susceptible.