Katie,

Having lived in North Carolina for 15 years before moving to Washington,
I've had a lot of experience with Fish Crows. They are common along the
coast there and in some areas are the only species present. During the
time I was living in North Carolina, Fish Crows became regular around
Chapel Hill where I lived, but only as a breeding species. They all
returned to the coast in winter. There were not many occasions when I
had to opportunity or need to distinguish the calls of Fish Crows from
those of juvenile American Crows. I was very familiar with the Fish
Crow before I ever noticed a juvenile American, and that was in near
Asheville, NC which is in the mountains, where Fish Crows do not normally
occur. That was in late summer, and I don't recall ever hearing young
American Crows sounding different from adults at any other time of year.
I can't say with certainty when American Crows attain the adult call, but
the most likely explanation for my not recalling the juvenile call very
often is that it is greatly restricted seasonally.

It would be difficult to describe verbally the calls of Fish Crows and
juvenile Americans in a way that would tell someone what they had heard.
You really have to hear them. The Fish Crow call has a somewhat nasal
quality that is quite distinctive. What you really need to do is listen
to a recording of it. Based on my own past experience with various songs
and calls, though, I'd say that it may not be very helpful after the fact.
My best guess is that if you were hearing two very distinctive types of
calls, and both species occur in the area at this time of year, the
likelihood is high that you heard some Fish Crows. The situation is very
different from that which obtains between American and Northwestern Crows.
I find all crows west of the Cascades to be problematical, partly because
I don't get over that way very often. But even the American Crows in the
Seattle area don't sound much like the eastern American Crows to me.

Mark Crotteau
Pullman, WA <crotteau at wsuvm1.csc.wsu.edu>