Before I talk about one of the coolest looking birds in North America, I’m going to start this off by letting you in on some bird words. First off, a raptor is any bird of prey such as a hawk, falcon, eagle, or owl that has physical adaptions for hunting larger prey. A buteo is a raptor in the broad-winged hawk genus and include the red-tailed and Swainson’s hawk. The term ‘buzzard’ (and you may be thinking of a vulture when you hear this word) is used in the old world to refer to these birds while in North America hawk has been the term used to refer to these birds. Alright now that we have some vocabulary lets talk about our bird of the week, the feathery-legged ferruginous hawk. Ferruginous hawks are the largest of the buteos in the world by weight, beak and foot size but has a smaller wingspan than the upland buzzard.
When in flight, look for the feathered legs which form a “V” just above the tail as well as a rather large head compared to the rest of the body. Like most raptors, these birds exhibit a light and dark morph which can makes it a bit trickier to identify. In the dark morphs, the inner wings are darker and more pronounced with white tail and flight feathers. In the light morphs, look for the white belly and rusty coloured shoulder pads. Adults and young fledglings give out a scratchy scream reminiscent of a donkey braying while alarmed and will dive bomb threats which produces a booming whoosh sound.
Adult ferruginous hawks build their nest in a variety of locations included on the ground and in elevated location such as lone trees, manmade structures, and boulders. When picking their elevated nest site, they will often build their nests on top of previous bird nests. Males bring building materials and females do the building using sticks, pieces of plastic, metal and occasionally bones to create the base of the nest. Softer materials such as dung and sod are used to line the nest, after all the females is going to be sitting there for an incubation period of 33 days! Females will lay a clutch of 1-8 cream-coloured eggs with brown splotches and will fledge the nest after 38-50 days.
Ferruginous hawks have seen a 64% population decline from 1992 to 2005 within Its range in Alberta and roughly a 30% decline within its entire Canadian range in the Prairie provinces. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) listed the ferruginous hawk as threatened in April 2008 and its Species at Risk Act (SARA) listing is at schedule 1 threatened as of February 2010. Main causes of the decline of their population have been associated with general habitat loss due to oil and gas exploration and urbanization. Ferruginous hawks have been hunted in the past but are now protected by the migratory bird act? Due to their specialized diet of Richardson’s ground squirrel’s, ranching practices that benefit fossorial animals will keep these buteos fat and happy. Artificial nest stands and brush piles have also been constructed to assist with nesting habitat. With proper ranching techniques and habitat conservation we will hopefully be able to stop the population and range reduction of these magnificent birds.
-Nathan (Nature Nate) Entz