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ROOSTSWhenever one speaks of crows, its wisest not to be too definite. The behavior of crows can vary widely from place to place. However, we can say that in many places, crows will gather in fall and winter to spend the night in large communal roosts containing several hundred to many thousand birds. Roosts as large as 200,000 or more birds have been reported. Communal roosts may remain in one location for a number of years or may shift from place to place in response to changing conditions. During the day, the crow population may be spread out over a very wide area, but perhaps an hour or more before dusk, birds will begin to fly towards the roost, collecting together into ever larger flocks as they get nearer. Generally, it seems as though most birds do not fly directly to the communal roost, but stop at nearby "staging areas". In some cases there may be several staging areas fairly near the roost. Often staging areas are in cemeteries or other areas where fairly open areas are surrounded by or interspersed with trees. Birds will fill the surrounding trees, hunt for food on the ground, and engage in general socializing. A roosting area may be virtually empty while nearby thousands of crows mill about in a staging area. As dusk approaches, the birds will abandon the staging area and gather in the communal roost. Often every suitable branch on every tree for a considerable distance will have a crow occupying it and there are constant alarms and mass flights and continual interactions of birds both in flight and in the trees. The noise level can be tremendous. As it grows dark the birds settle down and remain quite until dawn when they disperse again. Almost nothing is known about why crows form these communal roosts or of the dynamics of the populations involved. It appears that crows will travel considerable distances to a roost, but that not necessarily every crow in an area will travel to a particular roost every night. There is some indication that some individual crows may go to a roost some nights but not others. My own, thoroughly undocumented theory is that most of the crows at a roost on any given night are younger, unmated birds without their own territory. I also suspect that most of those younger birds come to the roost most nights while older mated birds with their own territory come only occasionally, if at all. According to this theory, the communal roost serves primarily a social function where birds challenge each other, find potential mates, and communicate, in one way or another, their individual and joint experiences. If this theory is correct, and most of the nightly inhabitants of a communal roost are young, non-breeders, it could explain why the destruction of birds at such roosts is always notoriously unsuccessful. In such a situation, even if you slaughter every bird in a roost, you leave the breeding population virtually untouched. Since competition for resources is now greatly diminished, the breeders are likely to be quite successful in replacing the lost population in a very short period of time. As I have said, most of the above is theory, supported by some observation. Little research on communal roosts has been done to date and your observations on the subject are greatly desired. Michael Westerfield 
Spending the night in a roost can be a messy business if you're on a lower branch. In the photograph to the right, the white on the crow's wing is not reflected light, but the remains of droppings that fell from above. Crows that slept in large roosts are often spattered with white the following morning. ROOST LOCATIONSIf you know of the location of a significant crow roost in your area, please send us the information.
Locations of fall/winter roosts.Town of Wallkill, Orange County, New York: 1/11/00 Location_Description: Caldor parkng lot between rte. 211 and rte.96 There is a roost of possibly more than 10,000 crows in the trees bordering the southeast corner of the Caldor parking lot. It has been there at least a couple of months. The lot is well lit so it is easy to see the birds and easy for the birds to see predators. The staging areas seem to shift continually. The largest staging area is currently across Carpenter Ave. (rte. 96) in the Orange County Fairgrounds. If you stand in the upper parking lot at dusk, thousands of crows stream over your head into the roost. While the roost is forming, crows within the roost fly out and change position frequently. Sometimes thousands of birds will leave the roost, fly back to the fairgrounds, then return to the roost. So many birds fly back and forth that there are near collisions. Once the roost is almost fully formed, the crows on the upper outside of the roost fly into the center trees. It takes a long time for the roost to settle for the night, possibly because of the lights. Since they can see to fly, they can keep changing their positions within the roost until after dark. While the roost is forming, the sound of calling crows is very loud. Once they have settled for the night, they are silent. This roost may move around. I don't think it was here last year. In previous years, I have seen rivers of crows streaming toward Dolsontwn Rd. on the other side of Middletown. There were thousands of crows in the trees on the edge of a cornfield. They are not there now. (Kelly Sheridan) ROOST SLAUGHTER ALERT! CHATHAM, ONTARIO, CANADA Chatham Crow Kill Authorized On Monday November 14, 1999 the Chatham-Kent municipal council voted to use any and all means to remove the crows from their roost in the industrial area of Chatham. Two council members voted against this motion and are to be commended Janet McGuigan-Kelly and Paul Watson. The rest of the council demonstrated that in spite of many opportunities and some excellent suggestions they had not taken the time to inform themselves about the basic nature of the problem. Myth, fiction and folklore seemed to form the basis for their decision. The original motion was to move the crows to a rural area but the rural representatives objected, they did not want the crows in their part of the county (where do they think they come from?) so this part of the motion was removed. The council then sat mute as the most bizarre episode unfolded. Chatham-Kent mayor Bill Erickson spent 10 minutes or so cross-examining the head of the public works department trying to refute line by line an editorial in the Chatham Daily News by Jim Blake which had criticized the mayor for his previous attempt to implement the crow kill without councils approval. The motion to remove the crows using any and all means was then approved without having any place to move them to. The Chatham Public Works Department in its report cautioned that there was a risk that the crows would break up in to smaller groups and relocate in residential areas if the present roost was disturbed. Any and all means are to be used against these crows. As there presently is a crow shoot being conducted in the county surrounding Chatham by the Mayors brother Richard Erickson these birds face certain annihilation either in town or in the fields. It is a sad commentary on our community as we face increasing challenges to our environment that we choose to destroy a highly social and intelligent species because it becomes a nuisance to some for a few months each winter. Chatham Ontario Canada is a city of 40,000 located in southwestern Ontario's cornbelt. It is or was home to a large winter crow roost. A regional council elected to represent all 110,000 residents of Kent County governs the Chatham-Kent municipality. UPDATE RECEIVED: 12/26/99 We seem to have been able to help swing things around 180 degrees in > Chatham with the power of the Internet. > City Council is changing it's tune. > Mayors brother is under investigation by the Ministry of Resources for > illegal killing of crows. > Local Rod and Gun Club wants no part of Crow killing etc. > Papers and TV are hounding the "Crow Killer Mayor" (Mayor is not > having a good day) CALIFORNIA LOS ANGELES (11/19/99) The Village Green in Baldwin Hills section of Los Angeles off Rodeo and between La Cienaga and La Brea. It is a condominium complex with large open grass areas interspersed with huge 50 year old trees. Behavior: This may be a possible roost. For the two years I've lived here, each year crows have collected just as darkness came. We watched them fly in in groups of 20-30 at dusk. There seemed to be birds stationed in trees along the way as the groups came in who would caw like landing lights at an airport and then follow them when the groups dwindled. I have hundreds of crow feathers I have collected from the ground under the big trees so preening is a big thing on their list. That may help indicate whether it's a roost or a staging area. Comments: They are not in the process of "roosting" here now, but I will let you know when it starts. We do have crows that live here year-round but it increases significantly during two months of the year. A description of nests would be >helpful. (submitted by Alinda Lord) CONNECTICUT NORWICH. November 14, 1999. For a year I had been searching for a large roost within crow-flight of my office in Willimantic, Connecticut. I was sure there was one, since I observed large flights of crows heading southeast about an hour before twilight through all of the fall and winter. The problem was following the birds across the hilly terraine between where I spoted them and wherever it was they were headed. They, of course, went "as the crow flies", while the roads I had to follow wound around the hills. By Spring of last year I was convinced that the big roost was in the southern part of Norwich, but I didn't have the time to hunt for it and no one I spoke with knew anything about it. But today I finally found it. Later on I'll get out the map and give precise directions, but for now, let me just say that if you haven't been at a crow roost at twilight, you've missed one of the most dramatic avian encounters possible. In the present instance, I chased isolated small flights around the area where I suspected the roost was located and finally discovered thousands of crows gathered in and around a large gravel pit. The trees were filled with birds and hundreds of others were walking about on the ground or perched on the tops or sides of the mounds of gravel. They paid little attention to my car, except to move a short distance away from it until I rolled down my window and lifted my camera. Then all of the birds - ON JUST THAT SIDE OF THE CAR - took off in agitation and flew to the trees. The ones in front and on the other side just continued as though nothing happened, despite the racket the others were making. As dusk approached, however, it became apparent that I had not found the roost at all, but just a "staging area" where crows gather before heading to the roost for the night. The birds began flying off and once again I followed in my car. In a very short time they arrived at a wooded hillside behind a shopping area and joined an even larger congregation of birds filling all the treetops and engaging in continuous cawing and social interactions in the air. Thousands of crows were present, but I could make no estimate of their actual numbers. I've posted follow up observations on this vommunal rost over at the "Personal Log" page on this site. MASSACHUSETTS WOBURN, MA. I finally found one of the local crow roosts, if it was any more obvious it would jump out and bite you. There are a bunch of willow trees at the Rte.93 South to Montvale Ave. exit ramp.At 9:30 at night the trees are loaded with Crows, right under the highway interchange's light towers. Some say the Crows are coming in closer to the city to roost under the lights to avoid night predation. Looks like thus may be true. 12/12/99 (Al P.) NEW YORK AUBURN. Large urban roost, nightly every winter for the past 5-6 years. 50,000 - 70,000 crows "stage" in historic cemetary at dusk then move downtown and roost along lake outlet over night. (submitted by Steve Johnson, 11/4/99) Currently the flock has chosen to roost mostly in the downtown arterial area between the east and westbound lanes of Rts 5 & 20. They also seem to gather in the Fort Hill cemetary area in the evenings before roosting downtown at night. (http://com-site.com/savethecrows/ OHIO Cincinnati MOUNT ADAMS, ONE OF THE FIRST SETTLED AREAS IN CINCINNATI ON THE OHIO RIVER. EVERY FALL THOUSANDS OF CROWS GATHER IN THIS HIGHLY POPULATED AREA OF CINCINNATI. THEY START ARRIVING IN LATE AFTERNOON, SPEND THE NIGHT, THEN FLY OFF IN THE MORNING. THEY GO IN GROUPS IN ALL DIRECTIONS THEN BEGIN RETURNING AGAIN IN THE LATE AFTERNOON. THIS CONTINUES TILL EARLY WINTER WHEN THEY DON'T COME ANYMORE. >Comments: IT SEEMS THIS IS SOME TYPE OF SOCIAL GATHERING. I WOULD LIKE TO KNOW MORE ABOUT THIS BEHAVIOUR.(Submitted by Bob Lindsay, 10/15/99) (This section will be added to on a continuing basis. Your comments and suggestions are welcomed. Other parts of the site are also under construction. This site will be continually expanding as the Crows.net Project grows.) |
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