Wednesday, March 7, 2012

Red-tailed hawk (Buteo jamaicensis) riding a thermal


Hawk flying over my yard on March 7, 2012. This is
 a juvenile red-tailed hawk.
Photo by Brad Sylveser. Copyright 2012.
Do not copy.
 For the purposes of this blog, I will count the skies overhead as a part of my yard. If I spot a bird flying overhead and it can be identified, I'll list it here. This morning I happened to look out my window and spy a hawk flying overhead. At first it seemed to be hunting, actively flying in a stright line, then hovering in place with quick wing beats as it focused on some object below.

It did not dive after whatver it spotted and instead began to circle lazily. Riding an uplifting thermal current to gain elevation. Hawks will sometimes ride these thermals all the way up to and even past cloud level. This particular hawk was quite high up by the time I got outside with my older camera. They look like they are just circling, but the rising air carries them quickly upward.

My camera has an autofocus feature and an infinite focus landscape setting. Depending on the height of the hawk, I might use either to catch a soaring bird. If the autofocus can get a good lock on the bird, that is the best option for my camera. Otherwise, using the infinite focus yields acceptable results for ID photos, if not nearly professional caliber. This particular camera has a 10X optical zoom. At any rate, the photo is good enough for an ID. The observed hovering behavior in a Buteo also suggests a red-tailed hawk, although it is not definitive.

Red-tailed Hawk hovering.
Photo by Brad Sylvester. Copyright 2012
 This hawk is definitely a member of the Buteo genus which can be differentiated by the length of the tail relative to the wings. Longer tails are found in Accipiters and shorter tails like this one, in Buteos. One of my favorite resources for identifying hawks is Hawks at a Distance. This book offers 3-4 pages of photos of each raptor and a separate page with dozens of silhouettes of each species to help make identifications under less than optimal conditions.

New Hampshire falls within the northeast migration corridor for a huge number of raptors that head south in the fall and come back in the spring. Some hawk watch station may see thousands of hawks ina single day during the annual migrations.

The red-tailed hawk, however, can be found in New Hampshire all year round, with Canadian birds coming down ffrom the north in the winter. When hawks migrate, they will usually ride thermals high into the sky and then glide for long distances preserving as much energy as possible.

When not migrating, they can often be spotted in trees at the road's edge along highways. This is a great vantage point from which to spot small animals darting out across the road. Unfortunately, this results is a relatively high number of red-tailed hawks being killed by vehicles as well. Despite this, they remain a very common New England hawk.

Quick facts about the Red-Tailed Hawk:

What do red-tailed hawks eat? Red-tailed hawks are carnivores and active hunters. The eat small mammals like squirrels and mice, but, according to the National Geographic Field Guide to the Birds of North America, they are not above taking reptiles, amphibians and birds as well. In New England, reptiles and amphibians would be snakes and frogs. Red-tailed hawks are not nearly as agile bird hunters as the Cooper's or sharp-shinned hawks, but will take birds if they have the opportunity for an easy strike.

Where do red-tailed hawks live: Red-tailed hawks live throughout North America up to the Arctic Circle and down to Central America.

What kind of habitat do red-tailed hawks prefer? Red-tailed hawks live in a wide variety of habitats. They often sit overlooking open grassland to scan for prey. They primarily hunt open spaces, but may also live in forests if there are nearby hunting grounds.

What eats red-tailed hawks? Not much eats red-tailed hawks with any regularity, but if caught on the ground, coyotes and other larger terrestrial predators will take them from time to time.

When is it here? Red-tailed hawks are found in New Hampshire all year round.

Where does it go in winter? Red-tailed hawks migrate south in the winter, but New Hampshire is still within the winter range for Canadian hawks and the summer range for more southern red-tailed hawks.

What's the life span of a red-tailed hawk? Nat Geo Wild puts the average lifespan of a red-tailed hawk in the wild at 21 years.

Nesting: Females lay 1-5 eggs in stick nests high off the ground according to Nat Geo Wild. The eggs take 4-5 weeks to hatch. Both parents care for the eggs and the young hatchlings.

Notes: Although most often identified by their prominent rusty red tails, not all red-tailed hawks have red tails.

Red-tailed hawk taxonomy:
Kingdom: Animalia (Animals)
Phylum: Chordata
Class: Aves (birds)
Order: Accipitriformes (formerly Falconiformes)
Family: Accipitridae
Genus: Buteo
Species: Buteo jamaicensis

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