Mobs of great-tailed grackles call cities home
If you’ve ever dined on an outdoor restaurant patio in Austin, you’ll remember the laser gun vocalizations and bold presence of the great-tailed grackle. You can’t leave your plate unattended for even a moment without the streetwise thief snatching a morsel.
This noisy, gregarious bird has not been deeply rooted in much of the Lone Star State for long. Some early writings on Texas avifauna (including J.K. Strecker Jr.’s 1912 checklist The Birds of Texas) found the great-tailed grackle only in South Texas, from San Antonio to Corpus Christi and south to the Rio Grande Valley.
Another barometer of Texas birds, H.C. Oberholser’s 1974 book Bird Life of Texas, claims the grackle did not arrive in Fort Worth until 1944 (and in Dallas until 1947). The explosion northward throughout Texas (and beyond) caught steam after World War II when Texans flocked from rural areas to the cities. These now-urban birds are as ubiquitous in cities as pigeons, rats and roaches.
There really is safety in numbers, which is one reason for the success in this species. During breeding season, males carefully guard harems of females with their young, reacting viciously toward perceived predators. Near the nest colony, grackles overwhelm visitors with numbers and noise.
The colonies can be large and are considered a nuisance by many. Anyone who parks a vehicle under a shady tree full of these nesting or sleeping birds soon regrets the decision because the droppings are not easy to scrub off.
Slender and long, male great-tailed grackles are iridescent black with a long shovel-scooped tail; females are smaller in drabber shades of brown and black. The voice of the displaying males is elaborate, with a variety of sounds, some sounding like a laser gun in a movie.
These city birds forage in open areas such as parking lots, in search of scraps from cars or garbage cans, and they forage lawns for anything that crawls. They sometimes even follow behind a lawnmower.
At one time, this species and its close relative, the boat-tailed grackle, a resident of coastal marshes straddling the Gulf Coast, were considered one species. Both are glossy black and noisy and congregate in sizeable flocks. There are slight differences, however, which have resulted in the split into two species.
The male great-tailed has pale yellow eyes, while the boat-tailed in Texas has brown eyes. The forehead and crown are very flat on the great-tailed, while that of the boat-tailed is slightly rounded or humped. This gives their heads very different profiles.
While you won’t find the boat-tailed grackle very far from coastal marshes with brackish water, the great-tailed grackle has a far greater range, one that continues to expand northward with the aid of the growing (human) urban population.
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