Sunday, March 24, 2019

And A Raven Came Calling…©




Minister Valley, Allegheny National Forest, Warren County, Pennsylvania, picture by the Author

Krrroooaaackkk!  It was a bright spring morning in Minister Valley, which is in Warren County, Pennsylvania, and is part of the Allegheny National Forest.  I was sitting at the mouth of a rock shelter, by a fire, boiling water for breakfast, when I heard Krrrroooaaackkk!

I said to myself, out loud, “that sounds like a raven!” a bird whose call I know well from my travels in Algonquin Park, Canada.  But, I knew that it couldn’t be a raven, because ravens were extinct in western Pennsylvania.  However, I knew what I’d heard.

So when I got back to Internet-land, I did some research, and here is what I found.

Unlike crows, whose range expanded due to human settlement and logging, ravens retreated as the forests shrank and the farms and cities grew, retreating until, in Pennsylvania, they only hung on in the wildest ridges of Allegheny and Appalachian Mountains.  Because of logging and settlement, ravens had almost vanished from Pennsylvania by the early 1900s and ornithologists thought that ravens would be extinct there by 1940.

However, ravens are adaptable and opportunistic birds, who have a greater worldwide range than any other bird, and somehow they managed to survive in the wildest parts of Pennsylvania’s central mountains.

Fast forward to today and the forests have regrown over large areas that were once farmland and the ravens have been leaving their mountain hideouts to return to places where they haven’t been seen for decades, such as Warren County, Pennsylvania.  Even though ravens have been slowly expanding their range, mountainous, wilderness areas are still where you will most likely meet ravens.  Today, in Pennsylvania, ravens are found mostly in the remote parts of the north-central counties of the Allegheny Plateau and south-central counties, of the Appalachian Mountains.


Distribution of the Common Raven in North and Central America, Fig. 1, by Boarman, W. I. and Heinrich, B., “Common Raven

Usually your first clue that a raven has come calling is its call.  Crows cannot “croak” they make a high-pitched “caw”, so if you hear a deep croaking call it is probably a raven.  Raven calls can be heard [HERE]

So, if you do hear a deep, croaking call, look up but how do you know if that black bird that you just heard is a raven or a crow? 

At an average of 20 to 25 inches in length, ravens are about 25% larger than crows, weighing on average 32 ounces and have a wingspan of four feet: crows have an average weight of 16 ounces.  In fact, crows are about the same size as a large hawk.  However, it is difficult to tell bird species apart by relative size, unless you can see both birds at the same time. 

The two most distinctive features that will help you distinguish between ravens and crows are; one, ravens have a thicker and heavier beak than crows, whose beaks by comparison are slim.  Also, the feathers on a raven’s throat are shaggy. 

Two, in flight, a raven’s tail has a distinct wedge shape and a crow’s tail is fan shaped.  When flying a raven has both a pointy-head and a pointy-tail.  Also, when flying, ravens keep their wings horizontal, while the wings of crows form a shallow vee.  In addition, ravens when flying, tend to soar long distances without flapping their wings, while crows rarely soar and must constantly flap their wings.

Adapted from “All About Birds: Similar Species: Crows and Ravens”
Lastly, ravens are usually found alone or at most in pairs, while the more gregarious crows are usually in groups of three or more, sometimes many more.

So, if you happen to be in the Pennsylvania wilderness and you hear a deep Krrroooaaackkk, look up perhaps a raven came calling…

Sources:

“All About Birds: Similar Species: Crows and Ravens”, Kevin McGowan, August 3, 2012, [Cornell Lab of Ornithology, Ithaca, NY], https://www.allaboutbirds.org/similar-species-crows-and-ravens/, Accessed 3/21/19

“All About Birds: Common Raven” [Cornell Lab of Ornithology, Ithaca, NY], https://www.allaboutbirds.org/guide/Common_Raven/sounds, Accessed 3/12/19

BirdNote, “Ravens and Crows - Who Is Who”, https://www.birdnote.org/show/ravens-and-crows-who-who, Accessed 3/20/19

BirdNote, “How to Tell a Raven From a Crow”, https://www.audubon.org/news/how-tell-raven-crow, Accessed 3/20/19

Boarman, W. I. and Heinrich, B., “Common Raven (Corvus corax), version 2.0.” In The Birds of North America, (A. F. Poole and F. B. Gill, Editors). [Cornell Lab of Ornithology, Ithaca, NY, 1999], https://doi.org/10.2173/bna.476, Accessed 3/12/19


Moyer, Ben, “Ravens, Often Mistaken For Crows, Have Rebounded Following Decades Of Decline”, Special to the Pittsburgh Post-Gazette Feb 19, 2012 https://www.post-gazette.com/sports/hunting-fishing/2012/02/19/Ravens-often-mistaken-for-crows-have-rebounded-following-decades-of-decline/stories/201202190516, Accessed 3/12/19



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