Blane Klemek column: The gray catbird is a secretive mimic
I've never observed a mockingbird. Perhaps one day I will. However, I do recall back in 2007 when a friend of mine from rural Bemidji, Sharon Campbell, called to inform me about her exciting observation next to her home.
As we talked on the phone, we compared notes. No, this bird was not a gray jay, nor was it a shrike. She described the bird exactly right, especially the distinctive white wing patches. Indeed, Sharon's uncommon backyard visitor was a northern mockingbird.
The northern mockingbird, related to our summer resident brown thrasher and gray catbird, belong to the family Mimidae. As the family name suggests, mockingbirds and others of the family are mimics. However, no other mimid takes mimicry to the heights and complexity that northern mockingbirds do. I look forward to hearing one someday.
For now, I will have to be content with listening to and watching the mockingbird's close relative, the gray catbird and brown thrasher. Both birds sing beautiful songs and emit interesting calls.
Most birdsongs are purely territorial and are delivered by male birds only. Male red-winged blackbirds, meadowlarks and song sparrows are just three that readily come to mind when I think of avian male passerines singing their hearts out. But there are many others, too.
As I mentioned, a couple of my favorite birdsongs, and birds, are the gray catbird and brown thrasher. But with limited space and only so many words per column, let's concentrate on the gray catbird this week, shall we?
Of all mimids, gray catbirds are the most widely distributed species. The handsome black-capped and black-tailed all-gray bird with rufous-colored undertail coverts, can be found in most of the lower 48 states and much of Canada. About 8 to 9 inches long with nearly a foot-long wingspan, gray catbirds are commonly grouped as medium-sized, long-tailed passerines.
But what endears and interests me most about gray catbirds is twofold: the appealing song of the male bird and both sexes' behavior of remaining close to the ground and hidden within the understory.
Regarding the catbird song, it can be described as a warbling of sorts and mixed with a collection of chips, chats, squeaks and rasping notes. There is arguably an imitating quality to the male catbird song, though I'm hard-pressed in picking out anything remarkably familiar or otherwise copied calls. Still, and wonderfully so, the musical diversity contained in the catbird song is very agreeable to one's ears.
As well, the somewhat secretive nature of this relatively shy bird is just as noteworthy. Where most songbirds frequently sing their territorial tunes from conspicuous perches, it is frequently the case that male catbirds choose less observable roosts from which to sing from.
Thus, you may very well hear the curious song, albeit in its rather subdued delivery, and you may believe that it comes from much higher aloft; but alas, you would be fooled by the bird's ventriloquist-like song and would, therefore, need to gaze downward into the shrubbery to find him.
To be sure, the gray catbird's chosen niche is within the confines of thickets where the bird not only sings from, but spends the majority of its days from, too. It helps explain why gray catbirds are such successful and obviously adaptable birds. Thriving nearly everywhere in semi-open areas that include dense shrub-growth, especially near human dwellings, gray catbirds are as at home in suitable urban habitats as they are in rural environments. Within these environs, catbirds seek out a host of insects and small fruits to eat. And like many other birds of the understory, catbirds also forage for food on the ground, scratching leaf litter as they search.
It's undoubtedly on the ground where catbirds can be observed performing another fascinating behavior. A neighbor of mine, John Baker, once emailed me with the story about a peculiar-acting gray catbird he had watched. He said the bird had landed on an anthill and then pecked at it a couple of times.
Continuing, he wrote, "As the ants poured over the bird's legs and body it picked them off and ate them, fluttering and flapping as it did so. It looked much like when a bird is drying of after bathing. The catbird stood on the anthill almost fifteen minutes before it got its fill."
I recalled learning about this avian behavior in my college ornithology class, so I informed John about what I knew. Not only was the catbird he observed probably relishing a hearty meal of ants, the bird was also "anting."
It's believed that anting helps to control external parasites, in addition to soothing skin irritations. Moreover, formic acid contained inside the bodies of ants is thought to work like a sort of pesticide on the birds' skin, keeping mites and perhaps fleas and other pests at bay.
No mention of the gray catbird should exclude the bird's telltale call. Its hoarse catlike mew is more than likely its claim to fame as an affiliate of mimid birds. Aggressive birds that fiercely defend their nest and young from predators, gray catbirds are also known to destroy the eggs of brown-headed cowbirds that are purposely laid in their nests by female cowbirds.
Gray catbirds, secretive mimics coming soon and living blissfully in your own backyard, provide us with plenty of reasons to get out and enjoy the great outdoors.
BLANE KLEMEK is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.