The Rough-legged Hawks of Creston

Rough-legged Hawk flying overhead

Rough-legged Hawk soaring overhead.

Creston is one of my favourite places to visit. I worked on my Ph.D. at the Creston Wildlife Management Area and over my six field seasons there I saw an incredible amount of wildlife. Now I also look forward to winter visits when I might see the wintering Rough-legged Hawks. Sometimes it seems that there is a Rough-legged Hawk on every telephone pole. I am exaggerating, of course, but these hawks can be quite numerous near Creston in winter – several may roost in the same tree over night. I have seen a Rough-legged Hawk and a Red-tailed Hawk soaring together over the same open field. The flats and fields near Creston are home for numerous voles, mice and other small prey that can support large populations of raptors- including the wintering Rough-legged Hawks. I remember exceptional summers where it was common to see the voles scurrying across the dike roads.

Rough-legged Hawk – looking for rodents?

Rough-legged Hawks breed in the arctic tundra and far northern forests. The tarsus (lower leg) is feathered – hence the name “rough-legged”. Like many other northern birds, the Rough-legged Hawk often migrates further south to find food. There may be a large number of these birds in wintering areas during prey shortages up north – an irruption.

fly by

A wintering Rough-legged Hawk near Creston

Raptors,including the Rough-legged Hawk, begin incubating after the first or second egg is laid. The first and second hatched young have a head start – they are older and stronger than young hatched from later eggs. This behaviour is like an “insurance policy” for the parents. The older, stronger young will most likely survive to fledge. In a year of food shortages there will not be enough resources to raise all the young from the eggs that are laid. In a good year with lots of food, the third or perhaps even the fourth chick may survive. Often, however, the elder chicks peck and kill the younger weaker chicks. It is a harsh reality that food is scarce and hunting is an expensive expenditure of energy – and difficult for young birds to master. Parental resources go to the young most likely to make it to adulthood – and the siblicidal behaviour of the stronger chicks ensures that they are the beneficiaries of those resources.

Rough-legged Hawks can be breathtakingly beautiful- soaring and hovering against that blue Creston sky. These birds face long migrations to come here to feed – and face a long migration back to breeding grounds. There may not be the food to support them or their young when they return. Like us however, they can best influence the future by surviving. And survival is a day to day proposition. I wish them well in their stay down here and on their journey back home. And I hope they make it back next year to bright skies and lots of voles.

Rough-legged Hawk watching me from over its shoulder

All photos and writing copyright Joanne A. Siderius 2013