Monday, November 7, 2011

Fish Crow

Two years ago, I took this photograph of a Fish Crow in the Merritt Island National Wildlife Refuge on the east coast of Florida. Since I previously bogged on American and Northwestern crows, I thought I would write a short note on Fish Crows. Fish Crows are hard to differentiate from American Crows--Fish Crows are smaller and have a similar, but more nasal call.

Fish Crows are found from southern New England and along the Atlantic and Gulf coasts to Texas. To my surprise, Fish Crows are also found up the Mississippi Valley to St. Louis, with vagrants even found in southern Ontario.  Throughout its range, this species has been expanding northward, with new colonies being formed often far from the previously know northern limits of their range (Mcgowan 2001).

Because Fish Crows often nest in cities and Minneapolis is on the Mississippi, I believe our city is a potential host to this small corvid. I have observed crows in Minneapolis that I would have identified as Fish Crows had I been aware of the possibility of discovering them here. One was a noticeably small crow that did not appear to be a young bird. I have also heard crows that sounded like Fish Crows. Both these field marks are notoriously subtle. The following links take you to American Crow calls and Fish Crow calls. (These files are used with permission of Thayer Birding Software's Birds of North America.) Young American Crows can sound like Fish Crows. The bottom line is that I am not sure how one might verify a Fish Crow's occurrence in Minnesota.

P.S. Alan Wormington, on the Ontario Bird Records Committee, writes, "Fish Crows are not accidental in southern Ontario.  We have 23 records, including one suspected nesting record."  

1 comment:

  1. Fascinating -- you can definintely hear the difference with the nasal tone.

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