Wednesday, October 24, 2012

Ravens

Common Raven over Copper Rock Rapids (Grass River), 10/1/12 - © Dave Spier

Here's a bird for Halloween. It was made famous as a symbol of death by Edgar Allen's poem.

Found completely circling the northern hemisphere, the Common Raven (Corvus corax) is one of the most widespread bird species in the world. Across North America, they occupy a wide swath from Central America to Alaska and east across most of Canada to the Atlantic, northern New England, and the Adirondacks, then south through a disjointed narrow band marked by the Appalachian Highlands. This range covers a great variety of climates and wild habitats, and sometimes they can be found near rural settlements and towns.


Ravens are larger than crows, but it's hard to judge size at a distance. In flight, ravens can be mistaken for hawks until they're overhead. Note the raven's long neck and long tail that ends in what's described as a "wedge" shape (meaning it's longer toward the middle of the tail). They are all black, but several hawk species have dark-phase members, which can be misleading. Like hawks, ravens also alternate flapping and gliding, unlike crows that have a steadier flight. When perched, ravens have shaggy throat feathers and long feathers covering their nostrils and the base of their heavy, thick bills (likened to a "Roman" nose because of the downward curve).

Common Raven eating a roadkill, Rts. 8/30 south of Speculator - © Dave Spier
The raven's diet is omnivorous; it eats anything edible. As scavengers, they can be found feeding on carrion beside country roads (in areas where they are common). I've heard people talk about ravens flying down the middle of a road as they search for new roadkills. You're less likely to actually see them when they're catching insects and rodents or eating eggs, birds, seeds, grain, berries, acorns and buds.

raven above DeGrasse, St. Lawrence County, NY

Ravens generally make croaking sounds, sometimes written "cr-r-ruck," plus gurgling and snoring sounds and woodpecker-like knocking calls. It's hard to realize they are actually songbirds (technically, passerines, or perching birds) obviously related to crows but also to jays, all in the Corvid family, and all can be year-round residents of their chosen locations. All About Birds has several recordings for your listening enjoyment. (There's also a page to help you ID and separate the crow/raven corvids.)

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect on  my Facebook pages including Dave Spier (photographic naturalist) or my personal page, Dave Spier with the profile photo, birding through a spotting scope. There is now a community page for The Northeast Naturalist.


Please report your sightings to eBird.

Saturday, October 13, 2012

Red-shouldered Hawk

Red-shouldered Hawk circling above DeGrasse on October 21, 2006 (note the wing tips pushed slightly forward, a typical soaring aspect for this species) - © Dave Spier

Red-shouldered Hawks (Buteo lineatus) can be expected anytime from mid-March through early November in the Adirondacks, based on the combined eBird bar chart for four northern New York counties. More of the reports come from St. Lawrence and Franklin, with few from Hamilton and a moderate number from Essex. The red-shoulder is considered a woodland species associated with mature deciduous and mixed deciduous-coniferous forests and likely to be found near rivers, streams, ponds and swamps. It typically avoids pure-conifer stands and it may hold to this pattern during migration.

Their primary diet is rodents followed by frogs and snakes. (A Michigan study placed small birds a close second behind mice.) It was getting late in the season for reptiles and amphibians when I found a red-shoulder soaring near DeGrasse in St. Lawrence County one October 21st.

Red-shouldered Hawks breed across the entire state of New York, with heavier nesting concentrations in southwestern NY, the Tug Hill Plateau and the Catskill Mountains. Slightly lower densities occur across south-central NY and the Taconics. There is a scattering of possible, probable and confirmed nest records across the Adirondacks with Essex County having the highest number of confirmed blocks at six. (Each Breeding Bird Atlas block is 5 x 5 km or roughly nine square miles.) Overall, nesting activity has increased statewide since the initial 1980-85 Atlas, although it may have declined slightly in the Adirondacks.

Rather than re-invent the wheel, so to speak, you can learn more about Red-shouldered Hawks at the All About Birds website along with a variety of photos. If you have The Sibley Guide to Birds, the species is illustrated on page 117. (There's a smaller Eastern version of Sibley's which I don't own.)

For a list of birds in St. Lawrence County and their seasonal abundance, I've linked to that eBird bar chart too.
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Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There is a separate Fb page for The Northeast Naturalist. Other nature topics can be found on the parallel blog Northeast Naturalist.