Daily Bird: Brown Thrasher

Connecticut Audubon is restoring habitat to help Brown Thrashers, which are declining in population (photo Carolinabirds.org/Dick Daniels)

June 18, 2020

Brown Thrasher
Toxostoma rufum

Revised and edited from a version published in 2016.

By Kathleen Van Der Aue, Chair of the Board of the Connecticut Audubon Society
The cinnamon-colored Brown Thrasher may more often be heard than seen as it spends much of its time hidden in its preferred shrub habitat.

A little bigger than a robin, the Brown Thrasher is on the list of Connecticut’s “Birds of Special Concern,” mainly because of loss of the messy shrubby areas it favors.

Where to find it: Recent sightings have been reported at Harkness Memorial State Park in New London, Brooklyn (Connecticut, not NYC), along powerline cuts in West Hartford, Skiff Mountain Preserve in Litchfield, Roberts Field in Bristol, and Connecticut Audubon’s Smith Richard Wildlife Sanctuary in Westport (check out this eBird map, which shows reported sightings in the state in June and July over the past 10 years).

You should look – and listen – for it in any shrubby thicket.

The thrasher is in the Mimid family, meaning it is a mimic much like its local cousins the Gray Catbird and the Northern Mockingbird. Its song consists of an assortment of sounds usually given in pairs (compare with the catbird’s single repetition and the mockingbird’s several repetitions of each phrase). It can be loud and lengthy. Listen carefully and you might hear bits of other birdsong.

The male and female pair up at the beginning of the nesting season and courtship begins with the presentation of a gift to the female; a twig or a leaf, something useful for the nest building ahead of them. The pair cooperate in building the nest, which is an open cup made of grasses, twigs and dead leaves placed low to the ground in a shrub.

Both parents incubate the speckled glossy pale blue eggs for about 12 days. The young are hatched helpless (atricial) but are ready to leave the nest within another 12 days. The parents will often dive bomb predators that approach the nest too closely. They are the largest species whose nests are parasitized by Brown-headed Cowbirds but they usually recognize the foreign eggs and toss them out.

Brown Thrashers eat insects, seeds and berries and are short-distance migrants, usually spending winters in the southern states. (The Brown Thrasher is the official state bird of Georgia, where it can be found in parks in Atlanta as commonly as American Robins can be found here.)

Before the 1970’s Brown Thrashers were among the most common of shrubland birds, found in thickets throughout the state. Their decline is linked to the regrowth of those thickets into forests, or the transformation of the thickets into lawns, with the most dramatic decline from the 1970s and ‘80.

Connecticut Audubon is creating, expanding, and managing shrub habitat at its preserves in Pomfret, Hampton, Montville, Sherman, and Goshen, as well as at the Smith Richardson preserve.

Brown Thrashers are still here, maintaining low numbers in the few shrubby areas still existing and those being created and maintained. It is doubtful that they will ever recover their former abundance unless the Connecticut landscape returns to old pasture and new forest.

Brown Thrashers will nest in suburban locations if we allow dense shrubby patches to remain in our yards. Because their nests are so low, their nestlings fall prey to predators like outdoor cats and raccoons and the dense vegetation helps to protect them.

Photo by Dick Daniels, Carolinabirds.org.