The Rabbit-footed Hawk
By Kenneth Turner Blackshaw
It's a cloudy, lowering day and I'm enjoying my jog out east of the airport in Madequecham Valley. There is a damp wind coming off the Atlantic, and the bird hovering ahead distracts me. It is large, and has its wings set, appearing motionless, like a kite hanging in the wind. This behavior reminds me of a Red-tail, but I'm suspicious. I've seen Rough-legged Hawks here in the past, but they typically beat their wings to remain in place. Now the bird tilts to the right and shifts its position about 50 feet before going into 'hang' mode again, about 35 feet above the ground. As it does this, I note the wings seem long and lanky compared to a Red-tail's and I catch a glimpse of white above the tail. Yes, this is a Rough-leg. I'm able to run almost underneath it, and I stare back over my shoulder as I run down the rutted road -- not normally a good idea, but this day I was lucky.
On the way back it is still there, but now shuts its wings and drops, feathered legs extended, and plunges into the edge of the marsh and disappears. A few seconds later, the hawk rises again, empty footed. So a field mouse has survived to live another day. This hawk's Latin name, Buteo lagopus, means 'rabbit footed hawk' and refers to the feathered leggings they wear, giving them insulation for the Arctic cold.
This is another bird that only birders know. Most people are content to call out a bird as a hawk and leave it at that. When they do this, there is often a vague recollection of hawks eating chickens. The more enlightened of us know that hawks like these prefer rodents to anything with feathers and are generally considered "beneficial". A century ago, when hunters killed huge numbers of hawks, Charles Wendell Townsend wrote in disgust; "Where a Japanese cabinetmaker would take his block and rapidly sketch the graceful poises of a hawk, the western barbarian takes his gun and kills and hardly glances at his beautiful and blood-stained victim, as he leaves it where it has fallen." Fortunately we 'western barbarians' are more enlightened now.
Rough-legged Hawks are Arctic hawks, only reaching here in the winter season and not every winter at that. Whether we see them depends on whether the rodent population up north 'crashes' and also if we are having, as Edith Andrews puts it, "a good mouse year." This year is one of those. In October and November I was noticing mice scurrying across the road in front of me, something I haven't seen other years. Perhaps it is because we had deep snow on the ground for such a long period last winter. The mice were free to frolic and procreate in their tunnels underneath the snow and predators like Barn Owls couldn't get to them. Indeed, a significant percentage of our Barn Owls starved to death in early 2003.
This season, Rough-legs weren't reported until our Christmas Bird Count when two were found working the cranberry bogs. Subsequently we found as many as three, one light-phase, one intermediate and one very dark one. Yes, this is another hawk with color phases. In the eastern U.S., about 40 percent of the Rough-legs are 'dark phase'. The dark ones are almost completely black, only showing silvery wing linings when seen from below, and just some faint banding on the charcoal tail. A 'light phase' Rough-leg looks quite pale all over from underneath, but retains identifying dark 'wrist' marks in the outer wings. Adult females are darker, with the lighter head and chest contrasting against the black belly giving almost the look of a Bald Eagle. Rough-legs are larger than Red-tails, but an eagle would be half again as large. Once you see a Bald Eagle in flight, everything else looks small.
This is the best year in a while for these dramatic raptors. We used to see good numbers of them on Christmas Bird Counts with a high of 13 in 1979. The past few years we have had none at all, so it is a treat to see them. Rough-legs are circumpolar. There are Rough-legged Hawks that nest all across the Arctic in Scandinavia and across Siberia. So, genetically the species has great resiliency, although Asian birds seldom mix with ours.
Man is so self-centered that we often think that when a species declines, it is something we have done. Things that are unseen by us can drastically affect the population of a species. Often it is an environmental thing that is beyond anyone's control, like whether the mice up in northern New England are having a good year.
So, if you are out in the wilds of Nantucket's east end, watch for a large, long-winged hawk hovering in the wind and try and get your binoculars on it. These are wonderful, graceful, successful mouse hunters. They'll be around perhaps until the end of April. Possibly next winter will be another good mouse year and they will return again!
George C. West creates illustrations for these articles.
If you enjoy social birding, every Sunday a group meets in the parking lot in front of the Nantucket High School at 8 a.m.
To hear about rare birds, or to leave a bird report call the Massachusetts Audubon hot line at 888-224-6444, option 4.