A Bird's Tale

Time for crows

Sat, 09/29/2012 - 8:00am

    The nights are getting chilly, the leaves are turning orange and yellow, and the kids are back in school. All signs of autumn. 

    But for us, one of the most telling indicators that fall is really here is the return of the evening flights of American crows to their favorite communal roost sites. 

    As autumn progresses into winter, these roosts get larger and larger, often containing hundreds, even thousands of birds. Roosts in some parts of the country have been reported to get into the tens of thousands. One near Ithaca, N.Y. (where we lived before returning to Maine) was estimated to host 50,000; and years ago a roost in Oklahoma was estimated to contain two million birds! 

    American crows are certainly one of the most recognized and most common birds in the U.S. and in most of Maine. They are intelligent birds. With their flocking behavior and conspicuous presence, including their raucous calls, many people find them enjoyable to watch and get to know better. 

    Grandfather Chase from Edgecomb was generally a fan of the crow. In younger years he may have done his share of complaining when they occasionally wreaked havoc in the garden, but later he came to enjoy them as fellow inhabitants of the land he loved. 

    As the young (crows) get older, they will come and go like teenagers, leaving the home territory for a time to hang out with roving flocks (dare we say “gangs”?) of adolescents.

    When a medical problem placed him in a Portland hospital for a time, he spoke often of how he would look out the windows and see crows hopping about on the rooftops, and felt like he had friends from home even in the unfamiliar surroundings of the big city. 

    Typically, crows are long-lived birds. A pair may stay together and inhabit the same territory for many years, accompanied by their offspring from years' past who sometimes help in feeding the nestlings. As the young get older, they will come and go like teenagers, leaving the home territory for a time to hang out with roving flocks (dare we say “gangs”?) of adolescents as they test their mettle and learn the ways of crow society. 

    Eventually, individual crows may leave and try to pair off with a mate to start a family, perhaps trying to carve out a small section from their parent’s territory, not unlike some human families! Beginning in late winter, you may see small groups of crows aggressively chasing each other around in territorial boundary disputes or, in some cases, as birds trying to establish a territory are kicked out and sent looking for a less hostile place to set up housekeeping.

    The intelligence and curiosity of crows is well known. One of our good friends has carried out research on crows for years, requiring him to climb high up into pine trees to put a unique combination of bands on the legs of each nestling crow in the population that he studied. These bands allow him to know who each bird is for the rest of its life and to study the behavior and interactions with other crows. 

    Unfortunately for our friend, the crows in his study population remember him as the horrible creature that climbs up to their nests as though he’s going to eat their babies. (They must think he is a terribly inefficient predator since their babies never disappear, but return wearing colorful jewelry on their legs.) As an indication of their intelligence, because all the birds now recognize him, if he tries to later go out and study their behavior, they all immediately surround him and sound off with loud, defiant calls of alarm instead of going about their usual crow business. Our friend has to hire students who are not known to the crows in order to obtain behavioral observations of the crows in his study population. 

    Since in the end his research will only end up helping crows, you could say that they are too smart for their own good!

    Dr. Jeff Wells is the senior scientist for the Boreal Songbird Initiative. During his time at the famed Cornell Lab of Ornithology and as the Audubon Society's national bird conservation director, Dr. Wells earned a reputation as one of the nation's leading bird experts and conservation biologists. Jeff's grandfather, the late John Chase, was a columnist for the Boothbay Register for many years. Allison Childs Wells, also formerly of the Cornell Lab of Ornithology, is a widely published natural history writer and a senior director at the Natural Resources Council of Maine. Together, they have been writing and teaching people about birds for decades. The Maine natives are authors of the highly acclaimed book, “Maine's Favorite Birds.”