Buteo Buteo

7

Want to ID a raptor in flight, by its silhouette?  Hawk Mountain has this great resource, read it over for more details on each.  Images aren’t to scale of course.

I think I might have seen a juvenile eagle last week down by the lake… maybe.  We’ve been enjoying our nearly daily sightings of the peregrine falcons too.  About nesting time for the Cooper’s Hawk we tracked last year… we should go down to the river and see if we can find them again.

3

The extremes of red-tailed hawk color morphs. White to very, very dark. Both are the same species, Buteo jamaicensis.

The bird on the left has an extreme lack of melanin production and the bird on the right over-produces melanin. Melanin is produced by cells called melanocytes, which also produce pheomelanin, which results in a reddish-brown color. Note that the bird on the left has a red tint to her tail even though her melanocytes aren’t functioning normally, this could be due to porphyrins and/or carotenoids contributing to the red color in red-tailed hawk tails as well.

Both birds still exhibit the common trait of being total derps (as demonstrated in the third set of photos).

4

Red-tailed hawk (Buteo jamaicensis)

The red-tailed hawk is a bird of prey. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West Indies, and is one of the most common buteos in North America. There are fourteen recognized subspecies, which vary in appearance and range. It´s measuring 45–65 cm in length, with a wingspan from 110–145 cm. The red-tailed hawk displays sexual dimorphism in size, with females averaging about 25% heavier than males. The red-tailed hawk occupies a wide range of habitats and altitudes, including deserts, grasslands, coniferous and deciduous forests, tropical rainforests, agricultural fields and urban areas. The red-tailed hawk is carnivorous, and an opportunistic feeder. Its diet is mainly small mammals, but it also includes birds and reptiles. Prey varies with regional and seasonal availability, but usually centers on rodents, comprising up to 85% of a hawk’s diet. Because they are so common and easily trained as capable hunters, the majority of hawks captured for falconry in the United States are red-tails. 

photo credits: Derek Ramsey, Greg Hume, Brocken Inaglory, Jason Crotty

Hawaiian Hawk (Buteo solitarius)

Also known as the ‘io, the Hawaiian Hawk is a Buteo spp. hawk which is endemic to the Island of Hawai'i in the Hawaiian island chain. However, fossil evidence indicates that it once inhabited the islands of O'ahu, Moloka'i, and Kaua'i. Like other Buteo spp. B. solitarius is a predatory, feeding on a range of small mammals, birds, and occasionally insects. 

Currently Buteo solitarius is listed as Near Threatened by the IUCN, as it faces threats from having a restricted range, habitat loss, and illegal hunting. B. solitarius also has been a hindrance to the reintroduction of the extinct in the wild Hawaiian Crow (Corvus hawaiiensis) as Hawaiian hawks, preyed upon individuals introduced into the wild. 

Classification

Animalia-Chordata-Aves-Accipitriformes-Accipitridae-Buteo-B. solitarius

Image: cliff1066

3

Red-tailed Hawk devouring a Rock Pigeon in front of St. James Anglican Church, King St. E., Toronto (Afternoon, late February,  partly cloudy, -19°C).

One of my favourite birding experiences: watching this hawk eating a pigeon for about 40 minutes in front of a Gothic Revival cathedral. I have also never been that close to a hawk in the wild. half way through the feast, a crowd of people started to form around this spectacle. The hawk, unfazed by the onlookers, did not leave until it finished eating the pigeon.

Raptors Of Winter