Saturday, June 23, 2012

Catbirds



Catbirds -- © Dave Spier

While many neotropical migrant birds are declining in population, a few hardy American species are doing well and perhaps expanding. One species in particular has adapted to human landscaping, assuming you have at least a scattering of trees and shrubs around your yard.

More likely to be heard than seen, its song is what I call jibberish -- a random assortment of notes and calls with no discernable pattern. Occasionally it will imitate portions of other bird calls, and that explains why it is one of three members of the Mimic Family. The most famous member is the mockingbird which precisely copies other bird songs (and other sounds, even frogs and sirens) and repeats them three or four times before moving on to a new sound. The second member of the mimics is the Brown Thrasher, now an uncommon bird in this part of New York. The thrasher sings each song twice and then moves on. The Gray Catbird (Dumetella carolinensis), on the other hand, says everything once, although it eventually returns to the same phrases in random order. Very little of its rambling repertoire is actual mimicry, although I have to be careful when he throws in pieces from a Wood Thrush. The catbird gets its name from its cat-like "meow." There have been times when I mistook it for a real cat.

Catbird singing from a dead maple (otherwise favored by the woodpeckers)
behind our garage.


At least one catbird likes our overgrown back yard, even though I keep portions mowed and maintain a wide trail inside the perimeter. I've been doing a lot of yard work and gardening and the bird seems to be getting used to me. It will "sing" from a nearby branch, sometimes out in the open. It's coloration is mostly dark gray with a black cap and some rusty red under the black tail. I guess this helps it blend into the shadows. Its tail is proportionately longer than most songbirds. Males and females are nearly identical. They're about the size of a robin but more slender.

The mulberries are just starting to turn from pink to red. If last year is any indication, when they begin to darken further, the catbird will start checking to see if any are ripe. Fruits and berries make up half their diet. The catbird in the opening photo has what looks like a Juneberry, most likely from the tree on the property line with our neighbors. The other half of their diet is insects, especially grasshoppers, crickets, and beetles. One or two catbirds may linger in the area through the fall into early winter if berries are plentiful. Once it gets really cold, the stragglers head for the Atlantic coast and piedmont east of the Appalachians. Some go as far as Florida and the Gulf coast.

One of my oldest photos, scanned from a slide taken in the early 70's when I got serious about birding. -- all 3 photos © Dave Spier

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