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Manitoba's Species at Risk

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Manitoba's Species at Risk Manitoba’s Species At Risk Threatened Ferruginous hawk Buteo regalis erruginous hawk (Buteo regalis) is the placed in large trees. In Manitoba, nearly Flargest of North American soaring hawks, three-quarters of the nesting pairs observed with a wingspan of up to 135 cm (53 inches). since 1990 have occupied artificial nests. In flight, the Ferruginous hawk has a light Three to five eggs are laid in late April or underside with reddish-brown markings on early May and are incubated by the female Any native Manitoba species the underside of the wings and on the legs, for about 30 days. The male spells off the likely to become endangered or forming a characteristic dark V against the female on the nest during incubation. at risk due to low or declining bird’s white underparts. Reddish-brown Young remain in the nest for six to eight numbers in Manitoba if the shoulders and a white window patch on weeks, and are dependent on adults for the upper surface of the dark primaries are food for several weeks after they learn to factors affecting it don’t also distinctive. improve. Threatened species fly. Birds leave their summer grounds in The Ferruginous hawk occurs in two colour September or October. Young first breed are declared as such by phases. Dark birds are chocolate brown when they are two or three years old. regulation under the throughout with a whitish tail and primaries. Adults can live for 20 years in the wild. Endangered Species Act. Although dark birds comprise up to 15 Ferruginous hawks hunt during the day, per cent of the population in some areas, in eating mostly ground squirrels and prairie Manitoba they probably make up less than dogs. Pocket gophers, voles, mice, rabbits 1 per cent of the population. and even birds will also be eaten. Adults Habitat frequently perch and hunt from the ground, using the sit-and-wait technique, These birds prefer open areas dominated by crouching at the mouth of a burrow and native grasses and scattered trees or shrubs, snatching up a ground squirrel as it with abundant ground squirrels for food. emerges. They also use trees, hydro poles Isolated trees or some other elevated and power lines as hunting perches. structure are usually required for the nest site, but the species occasionally uses a highly Distribution built-up nest on the ground. Ferruginous Ferruginous hawks nest in western North hawks typically avoid areas with greater than America, from the Canadian prairies south 30 per cent cultivation, sites that are prone to to New Mexico and Texas. In Canada, disturbance, or parkland areas where trees Ferruginous hawks are common in southern are abundant. However, a few pairs in Alberta and Saskatchewan. They are rarely Manitoba have been found nesting near found in southern British Columbia, and busy roads, in areas with no surrounding have recently re-established in southern grasslands, or in fairly large clumps of trees. Manitoba. In Manitoba, the species is Life History concentrated in southwestern Manitoba, as far north and east as Lenore, Brandon and Ferruginous hawks arrive in summer Glenboro. Non-breeding adults have been nesting grounds by late March. Males observed north to St. Lazare and east to usually return first, often coming back to Oak Hammock Marsh. Ferruginous hawks the general area where they were raised. winter in the southwestern United States Pairs often maintain the same mate. and in Mexico. Successful pairs traditionally use the same nest year after year, but unsuccessful pairs Status may select an alternative nest within their The Manitoba Conservation Data Centre territory. The nest is built by both adults lists the Ferruginous hawk as provincially using large quantities of sticks and roots rare (S2). Although it has declined in and lined with dead grass, sod and cow many provinces and states, it is considered dung. These birds are also comfortable apparently secure (G4) rangewide by using artificial nesting structures, consisting NatureServe. Since the early 1900s, of a wire basket filled with sticks and populations in North America have Manitoba’s Species At Risk nests by much of Manitoba’s nesting Cool population has provided pairs with sites that are further removed from potential disturbance. The sturdier artificial nests have Facts resulted in fewer losses of nests or young birds due to high winds. As a result of population Ferruginous hawks were not seen in increases across the Canadian prairies, the Manitoba for a period of about 50 Ferruginous hawk was downlisted to Special Concern in Canada in 1995. Manitoba years until a pair was found nesting continues to list the species as Threatened near Lyleton in 1983. By 1990, nesting because there are fewer than 40 nesting pairs numbers in Manitoba had increased to in the province and because of observed declines during the 1990s. With continued over 50 pairs. Recent declines in monitoring of nesting populations in the nesting success due to reduced ground province, the protection afforded by artificial nests, and some critical nesting areas being squirrel numbers resulted in only 37 protected through conservation agreements, nesting pairs in 2001. the outlook is quite positive. ● Get involved in recovery If you have nesting or foraging Ferruginous Nests are rarely more than 15 metres declined to about a quarter of their original hawks on your property, congratulations! estimated size. Habitat loss has reduced above the ground, but one unusually Your land management skills are helping to its historic range by about 50 per cent. support one of Manitoba’s rarest grassland high nest in a large tree in Populations have stabilized and even birds. Please contact Manitoba Conservation southwestern Manitoba was nearly increased in many parts of the Canadian at one of the numbers below to find out Prairies over the past 25 years, but the how you can help them nest successfully and 25 metres high. number of birds is still much lower than it encourage them to return, or to enhance once was. Declines are largely due to the loss ● your land for this and other native Manitoba and degradation of native prairie habitat due plant and animal species. This could include to human settlement, agricultural expansion maintaining grasslands or pastures used Heat stress can be a serious problem and resource exploration. Ferruginous hawks by Ferruginous hawks for hunting, avoiding for young birds in the nest as there are susceptible to disturbance by human excessive use of poisons that kill ground activities. Adult birds will often abandon a squirrels (the primary food source of the is often no natural shade from the sun. nest, and the eggs or young, if they are Ferruginous hawk), and erecting or To protect her young, the female disturbed during the nesting season. Other maintaining artificial nests. Human activity threats include destruction of nests due to will often stand with her back to the within 200 metres of active nest sites should be severe weather, and predation by racoons, avoided, especially between mid-March and sun and partially spread her wings magpies, crows or owls. Birds have also mid-June when the birds are most sensitive. been known to die from eating poisoned over the nest. ground squirrels. Manitoba Conservation ● Ferruginous hawk was listed as Threatened Wildlife and Ecosystem Protection Branch in 1994 by regulation under Manitoba’s Box 24, 200 Saulteaux Crescent Ferruginous and Rough-legged hawks Endangered Species Act. It has been assigned a Winnipeg MB R3J 3W3 status of Special Concern by the Committee are the only hawks whose legs are (204) 945-7775 on the Status of Endangered Wildlife in feathered down to the toes. Canada (COSEWIC), and is protected in www.gov.mb.ca/natres/wildlife/index.htm Canada under the federal Migratory Birds Manitoba Conservation Regional Office ● Convention Act. Western Region Brandon While raising their young, one pair of Stewardship and recovery (204) 726-6450 The Ferruginous hawk was listed as Ferruginous hawks consume an • nationally Threatened in 1980. A national average of 480 ground squirrels. Partners in production of this fact sheet: recovery strategy was approved in 1993. Manitoba Conservation, Although both adults bring food to the Its objective was to restore and maintain a Wildlife and Ecosystem Protection Branch viable self-sustaining population across the Environment Canada, Canadian Wildlife Service nest, only the female feeds the young. Manitoba Habitat Heritage Corporation breeding range of the species. Use of artificial Extirpated Species Endangered Species Threatened Species Vulnerable Species Any species once native to Any native Manitoba species Any native Manitoba species likely Species not regulated under Manitoba that has disappeared threatened to disappear through to become endangered or at risk the Endangered Species Act through all of its Manitoba range. all or most of its Manitoba range. due to low or declining numbers in but which could eventually Extirpated species are declared as Endangered species are declared Manitoba if the factors affecting it be considered Endangered such by regulation under the as such by regulation under the don’t improve. Threatened species or Threatened if the factors Endangered Species Act. Endangered Species Act. are declared as such by regulation affecting them do not under the Endangered Species Act. improve..
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