WatchList Species Account for Wood Thrush |
Qualifies for the list as a Declining Yellow List Species
The Wood Thrush nests in eastern North America, from northern Florida to east Texas and north to the upper Midwest and southern Canada. In winter it is found in Central America south to Panama. Its ethereal, flutelike song is a familiar sound across eastern deciduous woodlands.
Unfortunately, Wood Thrush populations have decreased over the last 30 years and in fact, the Wood Thrush is one of the Neotropical migrant species of highest management concern. Breeding Bird Survey data show a significant range-wide decline of 1.7% from 1966 to 1994.
The destruction and fragmentation of forests are major contributing factors in this decline. Although Wood Thrush will nest in 2.5-acre fragments and semi-wooded suburban areas, the birds have reduced breeding success in these smaller patches due to cowbird parasitism and nest predation from species such as jays, crows, raccoons and domestic cats.
Loss of primary habitats on the wintering grounds may also be responsible also for reduced populations; the birds probably do less well in secondary habitats, and if forced to wander are subject to higher mortality. Environmental pollution may also play a role in its decline.
Recent studies at Cornell indicate that increased amounts of acid rain make the Wood Thrush less likely to breed. One reason is that acid rain can cause calcium to leach from the soil, and in an environment of reduced calcium, female birds may lay eggs that are thin, brittle, and porous.