Ravens versus Crows in Utah

[Tim Avery <tanager at timaverybirding dot com>]

In response to MR. Wallaces email about Ravens and Crows:

The Common Raven is the predomninent year round species in the state of Utah. 
Americna Crows typically arrive for the winter months and are occasionally seen
at other times of year.  Both birds can be found in any type of habitat,
depending on a food source that they can use.  During the winter months
American Crows will be found in most areas below 4500 feet in elevation,
typically large fields, and low lying open areas are favored.  However it is
not uncommon to find a Crow in the mountains again, depending on food sourse. 
Ravens may be found in small groups but usaully don't flock as large. 
Occasionally a large flock 500+ Crows can be seen roosting in treees and or
fields.  I myself have seen this on the Pony Express route to Fish Springs
where a field was covered in the early morning hours with a flock near this
size.  On the other hand Colby Neuman has seen small numbers near the
University of Utah during the summer months, showing that the birds can be
found at any time of year.

As for differences in the bird here is a quick breakdown:

The largest American Crow is only as large as the smallest Common Raven.  In a
comparison shot:

http://tanager.smugmug.com/gallery/183068/1/6962018

It can be seen that the Raven in the forground is much larger than the Crow
behind.  These birds were about 4 feet apart for an idea on size differnce. 
Most Ravens are about 25" in length compared to an average crow size of 19 -
20".  The head are drastically different in shape, with a Crows being more
rounded and a Raven being more block shpaed.  But again with birds, there is
variation within shape and size.  One thing to note on the head of a raven is
the "beard", which the Crow lacks.

The bill is a great clue in pure size.  The bill on a Raven is large and thick,
where the crow bill is a thinner more pointed bill.  And in comparison to head
size the bill on a raven is larger compared ot the head, than the bill on a
crow.

The tail in flight is a good key, wiht a Crow tail being more squared off, and a
Raven tail having a rounded edge appearnace.

The overall color on both is black, and although both have a sheen, the Common
Raven appears to be more of a matte bird overall all, whereas the Crow is a
shiny bird, with a glossy coat.

That I think is a pretty helpful breakdown of the two species, which will
compete for food oftern, instead of sharing, as most scavengers do.

Here is a link to a Crow photo:

http://tanager.smugmug.com/gallery/183068/1/6962022

And here is a link to Jacks Raven:

http://home.earthlink.net/~birdutah/h_raven_comn.html

As you can see both appear a bit shiny, but the crow is more so than the raven.

Good Birding

Tim

Salt Lake City, UT or Beloit, WI
http://www.timaverybirding.com

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