The Black Bird Invasion
Every year the University of Texas Medical Branch (UTMB) in Galveston, along with other sites throughout the island, is hit with a blizzard of black birds, mostly Great-tailed Grackles mixed with European Starlings. During the day the birds are not very noticeable, just part of the local avian life. But at dawn and at dusk, they congregate to roost in trees and on ledges, filling the dim sky with the din of their cry and the muted flutter of hundreds, perhaps thousands, of wings. I need not go into detail about the side effect of these roosts upon the sidewalks and lawns under the trees.
These nocturnal deposits have led many residents to attempt multiple strategies to convince the roosting birds to find a new set of trees for their bedroom. We have had plastic owls with mechanically rotating heads, tapes of hawks and other raptors, booms and bangs of recorded fireworks and shotguns, but none of them seem to have a long term impact. The grackles, after all, were roosting here long before we arrived, and behave as though they have the right to continue regardless of what we may think of them. The starlings have joined the grackles over the last century but seem to be equally assured of their property rights. I like to point out to those who complain about the grackle/starling invasion that the primary food of both species when they are here is insects, especially yummy larvae. If we have, say, 200,000 birds in the combined flocks (which is easily imaginable) and they stay for 30 days and eat, on a guess, five insects each every day, then the island has been spared 30,000,000 bugs that would still be around if the flock were to leave. And if that’s not a blessing, I’m not sure what is.
