This evening while out running a few errands I noticed a big flock (80+) of crows at the Fairview Cemetery off of Stanley Avenue in Niagara Falls. Pulling into the cemetery with my windows open I could clearly hear a few crows - both Fish and American. I approached the flock on foot and was surprised that the vast majority of the calls that I was hearing belonged to Fish Crows. I made a short video of part of the flock in which the high proportion of Fish Crows is easily apparent.
While it is impossible to know just how many Fish Crows were a part of the flock, I think a conservative estimate is that at least 50% of the flock are Fish Crows. That being said I wouldn't be surprised if the ratio was closer to 70% or 80%. Given a ratio of 50%, at least 40 Fish Crows were present.
It seems that most of the Fish Crows I have been seeing are undergoing primary molt, making it appear that they are missing chunks of feathers along their wings. I have not seen too many American Crows lately but from what I recall, most do not have easily visible primary molt occurring. Sure enough most of the crows in this flock tonight exhibited the classic look of missing primary feathers. Is this a semi-reliable field mark at this time of year? I guess I should go do some research on crow molt!
Since the first Niagara records of Fish Crow in 2012, sightings in the region have slowly increased. This spring, a group of at least 14 birds frequented the Port Weller area of St.Catharines, at the time representing the high count for the province. The group of birds from this evening blows that out of the water. Clearly Fish Crows have a big presence in Niagara, though we have not yet found a nest! That will be a project for next spring.
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| Fish Crow - St. Catharines, Ontario (April 22, 2017) |
5 comments:
Holy crow! We still cannot get any in Chatham-Kent!
Adult American Crows in Newfoundland in heavy wing and tail moult right now.
American Crows in Newfoundland are currently showing large chunks of air in their wings and tail as they are in heavy moult.
Nice to hear those calls in the cemetery.
Interesting article on crow ID: http://www.birds.cornell.edu/crows/FishCrow.htm
The following paragraph is of interest. This is in regards to the crows in Ithaca NY, so just over 200 km from Niagara Falls, as the crow flies.
"During the summer the two species can be distinguished by their stages of molt. In much of their range American Crows breed a month or more earlier than Fish Crows (Johnston 1961, The biosystematics of American crows, Univ. of Washington Press; Clapp and Banks 1993, Raven 64: 90-98; McGowan 2001, Fish Crow (Corvus ossifragus) in Birds of North America, No. 589). In upstate New York American Crows start incubation the first week of April, while Fish Crows don't start until May. Most birds do not molt until they are finished breeding, and the molting schedules of the two crows reflect the month difference in their breeding schedule. The earliest Ithaca American Crows (non-breeders and those whose nests have failed) will start molting in June and will be finished by the end of September. Ithaca Fish Crows, on the other hand, start molting in late July and don't finish until October."
Give it a few years :)
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