Kiting is a common activity for Iowa's raptors
Several large raptors were seen in what appeared to be hovering flight as we recently drove across eastern Iowa on I-80. A few birds such as hummingbirds and kingfishers routinely hover in one spot even in calm air. Some other songbirds can hover briefly, but it costs them too much energy to hold for long. The hawks I saw weren’t actually hovering, but were doing something called kiting. They were actually flapping and gliding forward into the wind but controlling their airspeed and altitude to stay over one spot. Kiting allows them more time to watch for movement of any possible prey.
The birds I saw kiting included three rough-legged hawks and one red-tailed hawk. Other raptors that can be seen kiting in Iowa include colorful little kestrels, harriers and ospreys. Rough-legs nest in the high Arctic and occasionally come this far south during the winter. Red-tails seen here during the winter may be local nesting birds or winter migrants from farther north. A few winter kestrels may be local birds, too, but others are winter migrants. Harriers are grassland and wetland birds that were once known as marsh hawks. A few still nest in Iowa, but they’re not here in winter. Ospreys, also known as fish hawks, are here only in open water season.
Each of these raptors handles kiting in a slightly different way. All kiting is done flying into the wind. In fact, just like flying a kite, some wind is required for raptors to kite effectively. Rough-legged hawks are better at kiting than the slightly smaller red-tailed hawk, and they kite more often. Their wings are longer and narrower, a bit more like the long, thin wings of a sailplane. They can kite over flat, open grassland by alternately flapping and sailing.
Their high-lift wings allow them to maintain position even in a light wind. Red-tails can sometimes be seen kiting just above steeper highway grades. Wind flowing up over a grade (known as ridge lift) gives them the additional lift they need to maintain altitude with their shorter, wider and slightly less efficient wings. Red-tails can soar on thermals, but seldom, if ever, kite over open, flat land where there’s no ridge lift.
Kestrels, once known as sparrow hawks, kite into the wind on rapidly fluttering wings. They’ll hold over an area for several moments as they study the ground for possible prey before moving to another spot. Larger raptors glide down to capture their prey. Kestrels go from kiting to a bullet-like vertical pounce in the blink of an eye.
Harriers seldom fly very high unless migrating. Their long, narrow wings flap slowly as they bob and weave low over grassy areas with their wings often held in a V over their backs. They may pull up into several flaps of kiting when something catches their interest; then drop quickly if prey is spotted. Ospreys flap and soar over water as they search for fish near the surface. Like harriers, they shift to a brief moment of kiting with their wings flapping high above their backs when something catches their attention. If a fish is sighted, they drop in a near vertical plunge feet first into the water with their wings still held high.
Raptors can often be seen along our larger highways in winter and during migration. Miles of empty harvested fields offer little for them to hunt. Roadside vegetation and occasional CRP grassland is often the only habitat that supports birds and animals that raptors depend on for food. Keep an eye out for raptors that seem to be going nowhere as they kite above roadsides while looking for a meal.
Steve Lekwa is the former director of Story County Conservation. Contact him at email@example.com.