Subject: [Tweeters] re: Ferruginous Hawks
Date: Apr 9 19:36:11 2010
From: Scott Downes - downess at charter.net


Biology of this species in Washington is varied. Both here and in the Columbia Gorge of Oregon I wind up working with this species often for work and for pleasure. They time their arrival to breeding areas around the peak of emergence of ground squirrel colonies. In Washington, this is typically Washington Ground Squirrel (a federal candidate species) however west of the Columbia River in areas like Klickitat County, Yakima County and Benton County where the species isnt very common any longer, they feed on Townsend's ground squirrel (State Candidate) a related species to Washington ground squirrel. They can nest in cliffs, escarpments and in the southern part of the state, where Junipers are present, in Juniper. Recent evidence that has been done on some birds also shows that in Washington and Oregon some birds when they leave OR/WA actually travel to the upper prairie areas of Montana, Dakotas and Wyoming to feed in the late summer before heading south. The two biggest reasons this species is declining is that its is heavily tied to shrub-steppe areas (and need ground squirrels or prairie dogs in other areas of their range as food base) and does not do well around human disturbance (as mentioned earlier). Shrub-steppe species as a whole are on the order of old growth species in terms of declines. If you look at some of the key species for this habitat in Washington that are shrub-steppe obligates most of them are either listed or candidates for listing due to habitat declines. Ground squirrels start to go into estivation (heat form of hibernation) in June so the ferruginous hawks nest early, and then leave for other food sources during mid to late summer.

In addition to sage and sharp-tailed grouse which birders are probably more familar with declines you have:

Burrowing Owl-State Candidate and declining range wide
Washington ground Squirrel- State Candidate, endangered in Oregon.
Sage Thrasher- State Candidate
Sage Sparrow-State Candidate
Ferruginous Hawk-State Threatened
Golden Eagle- State Candidate
Both Jackrabbit Spp- State Candidate

People get the idea. In many ways good quality intact shrub-steppe is arguably the most rare habitat in the state. For those that haven't gotten to appreciate this wonderful habitat I highly encourage people to come bird and hike in good intact shrub-steppe places like the Quilomene, Beezley Hills, Yakima Training Center (and Waterville Plateau has some decent chunks as well) from now until early June. I would hope that large chunks of shrub-steppe continued to be around so that we can all enjoy this habitat and wonderful birds like Ferruginous hawk, but many don't value it so the long-term survival of some of these species in the state is questionable. We should consider ourselves very fortunate when we get to enjoy whether its a soaring Ferruginous hawk or a displaying sage thrasher!

Scott Downes
downess at charter.net
Yakima WA