Gray Catbird
Dumetella carolinensis

Migratory Status: Neotropical migrant

PIF Population Estimate: 10 000 000

Percent of western hemisphere population breeding in boreal forest: <25%

PIF Maximum Detection Distance (m) : 125

Canadian BBS Population trend: -0.4 n.s. (-1.2 to 0.3)

Life History

The Gray Catbird is named for its “mewing” call, which for some, sounds much like a cat. Males have a vast vocal array, due in part to special modifications to their vocal organs that allow the birds to sing with two voices simultaneously. Songs include a repertoire of more than 100 different types of rambling whistles, chatters, squeaks, warbles, and at times, mimicry of the songs of other species. Songs may last up to 10 minutes in duration and are sung in seemingly random order, sporadically punctuated with the familiar “mew”. The female rarely sings, but occasionally will quietly duet with the male.

Similar in shape, but smaller and slighter than an American Robin (Turdus migratorius), catbirds are mostly sooty gray in colour, except for a black eye, cap and tail, and chestnut undertail coverts. Western populations are generally paler than eastern populations. Sexes are indistinguishable from one another. Catbirds, at times, are skulkers and stay hidden for long periods in dense foliage while they sing, but eventually reveal themselves by perching in the open while in song.

Gray Catbirds breed throughout southern Canada, except for Vancouver Island, and east of the western mountain ranges of the United States across the Mississippi valley and through to the Atlantic coast. Gray Catbirds nest at lower elevations in dense, shrubby vegetation, vine tangles, riparian thickets, and deciduous early successional habitats. Nest stands are found along clearings, roadsides, fencerows, farmlands, streamsides, and residential areas. Uncommon in coniferous stands, catbirds prefer edge habitats and are generally not found in forest interiors.

In some areas, nearly half of all catbird nests are parasitized by Brown-headed Cowbirds (Molothrus ater). However, catbirds are one a few species that have learned to recognize cowbird eggs and quickly remove the foreign eggs from their nests. As a result, cowbirds are rarely successful at parasitizing catbird nests. Gray Catbirds may destroy the eggs or kill the nestlings of other songbird species. It is unknown if this behaviour is a competitive response or a foraging behaviour, as they are also known to eat the eggs of other species.

Reference(s)

Cimprich, D. A., and F. R. Moore. 1995. Gray Catbird (Dumetella carolinensis), The Birds of North America Online, . A. Poole, Ed. Ithaca: Cornell Laboratory of Ornithology; Retrieved from The Birds of North America Online database: http://bna.birds.cornell.edu/bna/species/167