The Northern Harrier breeds from central Alaska, excluding the north slope, east across the Yukon and western two-thirds of Mackenzie to Manitoba, Ontario, southern Quebec, New Brunswick, Nova Scotia, Prince Edward Island, but not Newfoundland, and south including British Columbia, Alberta, Saskatchewan south to central California and east across northern Arizona, New Mexico, northern Texas, Oklahoma, Missouri, the southern two-thirds of Iowa, Illinois, southern Wisconsin, Indiana, southern Michigan, northern Kentucky, Ohio, West Virginia, northern Virginia, Pennsylvania, New York, Massachusetts, Connecticut and Rhode Island. In southern parts of the breeding range the Northern Harrier is present year-round which includes a band across the United States from Washington south to central California and east across southern Idaho, Nevada, Utah, Colorado, Kansas, Missouri, Illinois, Indiana, and northeast to Nova Scotia.
This species formerly bred in southern California, northern Baja California and Florida.
It winters from extreme south coastal Alaska, coastal and extreme southern British Columbia and southern parts of the breeding range south through the rest of the United States.
There are three subspecies of the Northern Harrier, only one of which occurs in North America. It is referred to as C. c. hudsonius.
The Northern Harrier also occurs in South America, Europe, and Asia.
MIGRATION
Southern populations of the Northern Harrier are generally nonmigratory but most northern and central populations migrate. Migrants travel singly, or in small groups. Harriers use thermals to gain altitude, like buteos do, but generally employ much more flap-and-glide flight to cover distances. They often migrate at generally low elevations but are also capable of high flight. They migrate throughout the day and sometimes at night. They readily migrate in poor weather which grounds other migrant hawks. They will interrupt their travel to hunt , using their usual low level coursing. Harriers cross water readily except for huge expanses like the Great Lakes and the Gulf of Mexico. Migrants have been seen crossing narrower bodies like the Bay of Fundy, Delaware Bay, Yakutat Bay (Alaska), and the Gulf of Maine, and have reached Bermuda, the Bahamas, and the West Indies.
Fall migration begins in August with the dispersal of juvenile birds, which precede older birds. Migration continues until late in November in the northern United States, making the fall movement of Northern Harriers the most protracted of any North American raptor migration. Peak movements at both Hawk Mountain, Pennsylvania and San Francisco, California, are from mid to late October. Huge concentrations do not occur since the birds migrate over broad fronts, both inland and along the coast. The largest numbers have occurred at Cape May, New Jersey (3000+ fall, 1980).
Spring migration begins in February and March in Central America and is protracted, continuing into mid May in the northern United States and into the first week and a half of May in southeastern Alaska. There appear to be no great peaks in numbers. Males generally arrive before females, and females before immatures.
#Which species has this range?;question\Q12\Q12.wav
