Asio flammeus (Pontippidan) short-eared owl

State Distribution

Photo by Don Baccus

Best Survey Period

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Status: State endangered Recognition: The short-eared owl is a medium-sized owl with females slightly larger in size than males (Holt Global and state rank: G5/S1 and Leasure 1993). This species has long wings and a short tail with a tawny, boldly streaked breast and a Range: The short-eared owl is one of the world’s most belly that is paler and more lightly streaked. The face is widely distributed owls (Holt and Leasure 1993) and it round with small ear tufts. The flight pattern of the occurs as a resident or visitor on every continent except short-eared owl is erratic and low to the vegetation. Australia (Evers 1994). In North America the short- When in flight, pale wing patches are visible near the eared owl breeds from northern Alaska and Canada, ends of the upper wings and dark “wrist marks” may south to central California, and east to Maryland and be observed on the underside of the wings (Johnsgard Prince Edward Island (Johnsgard 1988, Evers 1994). 1988). The vocalization of the short-eared owl, which is typically heard only in the spring, can be likened to State distribution: The short-eared owl probably was that of a barking dog. Also, young make a distinctive never a very common resident of Michigan. Early nest begging call (“Psssss sip”), which may be heard during records from the late 1800’s and early 1900’s are the later portions of the nesting season (Holt and minimal, most of which were documented in south-east Leasure 1993). Michigan. However, these early records probably do not reflect the true distribution of owls but rather the Best survey time: The best time to survey for breeding density of observers during that time period (Evers short-eared owls is from May through mid-July. Winter 1994). During the mid 1900’s scattered breeding surveys should be conducted from late November records were documented in several southern Michigan through early March. Short-eared owls can be surveyed counties which included Calhoun, Clinton, Lapeer, by watching grasslands/emergent wetlands for the Saginaw, and Wastenaw (Zimmerman and Van Tyne presence of the bird during the late evening hours. 1959). Since then, very few breeding records have been Vocalizations by adults also may be heard during early recorded in Michigan. The following counties have had portions of the breeding season and begging calls from recent records (since the 1980’s) of breeding short-eared the young may be heard during the later portions of the owls: Chippewa, Mackinac, Osceola, Isabella, Gratiot, breeding season. Clinton, Lapeer, St. Clair, Macomb (Evers 1991), and Hillsdale (Natural Heritage Biological and Conservation Habitat: Short-eared owls require large (typically Data System 1999). > 250 ac) open grassland or emergent wetland habitats such as prairie, hayfields, fallow fields, small grain

Michigan Natural Features Inventory P.O. Box 30444 - Lansing, MI 48909-7944 Phone: 517-373-1552 short-eared owl, Page 2 stubble, and marshes for breeding habitat (Dechant et abundance, distribution, and vulnerability of prey al. 1998, Johnsgard 1988). However, smaller species (Block et al. 1994, Dechant et al. 1998). grassland/wetland fragments as small as 75 ac. can be Fragmented openland habitats increase the likelihood of utilized particularly when the surrounding landscape is nest destruction from predators such as skunks, largely openland habitat (Dechant et al.1998, Herkert raccoons, foxes, and coyotes (Sample and Mossman 1999). In the winter, congregations of short-eared owls 1997). Management should focus on maintaining large exploit old fields, marshes, and hayfields. Pine contiguous areas of grassland, marsh, or wet meadow. plantations (Kinziger 1997), preferably with an average This could be accomplished through conservation height of 5 feet, or individual conifer trees adjacent to easements, land purchases, utilization of the openland/wetland habitats are preferred roosting habitat Conservation Reserve Program (CRP), etc. (Johnson in the winter and may provide a survival advantage over 1996). Management practices that increase the quality ground roosting sites, particularly when snowfall of habitat and prey-base include burning or mowing exceeds 2” (Bosakowski 1986). every 3-5 years (Dechant et al. 1998). Mowing or burning should not be conducted from mid-April Biology: The short-eared owl is migratory but some through mid-July in order to abate nest destruction and birds over-winter in small groups in southern Michigan. mortality of young birds. Ideally fields should be When short-eared owls arrive to their breeding grounds mowed from the center outward to allow escape of in the spring they begin courtship displays, which are fledgling owls, as well as various other grassland bird often observed during daylight hours. Breeding species (Sample and Mossman 1997). When burning territory size (typically > 170 ac.) and use from year to large contiguous area (> 100 ac.) no more than 1/3 of year may vary depending on food availability. Nest sites the habitat should be burned annually. In smaller are placed on the ground and consist of a bowl-shaped fragments (< 100 ac.) ½ the site could be burned depression that is lined with grasses and downy feathers annually. If several small sites are within close (Holt and Leasure 1993). Eggs are typically laid by proximity (within 1 mile) of one another, then some of mid-May with clutch sizes varying between 4-7 eggs. If these fragments can be burned entirely while other nests are destroyed re-nesting may occur. Eggs are small fragments are left unburned. Leaving unburned incubated approximately 24-29 days and young hatch portions of large openlands or leaving smaller fragment asynchronously (Johnsgard 1988). Young begin to beg entirely unburned provides refugia for owls, as well as for food at 3-4 days old and wander around the nest site various other wildlife species, and creates a diversity of when approximately 14-18 days old. Adults micro-habitat conditions for multiple grassland bird aggressively defend wandering juvenile birds. Young species (Sample and Mossman 1997). typically can fly at 24-27 days old and family groups may remain together throughout the entire winter, often Research needs: Numerous research needs exist for forming winter foraging territories (Evers 1994). The the short-eared owl. Systematic inventory of breeding short-eared owl’s diet is primarily composed of small and wintering grounds in Michigan is needed in order to mammals, particularly voles, with smaller percentages get a better sense of distribution patterns across the of the diet encompassing various openland/wetland bird state. Also, more research on the impacts of prescribed species. Vole abundance has been linked directly to nest burning and mowing, factors effecting nest productivity, productivity and habitat utilization (Dechant et al. and analysis of landscape and micro-habitat attributes 1998). Short-eared owls hunt primarily at dusk by that influence habitat utilization and nest productivity. taking prolonged foraging flights, usually less that 6 ft. above the vegetation and typically flying into the wind. Related abstracts: Red-legged spittlebug, blazing star They often hover when foraging and quickly descend borer moth, Culver’s root borer moth, emergent marsh, vertically on prey. Occasionally short-eared owls hunt Blandings turtle, eastern massasauga from low perches (e.g., fence posts, shrubs, etc.) by watching open areas for prey. When prey is spotted Selected references: from these low perches they will fly out rapidly and pounce on the prey. Approximately 20% of all attempts Block, W.M., M.L. Morrison, and M.H. Hildegard. to procure prey are successful (Holt and Leasure 1993). 1994. Northern Goshawk Ecology and Management. Studies in Avian Biology No. 16. Conservation and management: The primary threat Cooper Ornithological Society, to this species in Michigan and throughout the mid-west Sacramento, California. is alteration and destruction of habitat due to development, intensive agriculture, and successional Bosakowski, T. 1986. Short-eared owl winter roost changes to habitat (Evers 1994). Habitat manipulation strategies. American Birds 40:237-40. and destruction directly impacts the species by alteration of suitable nesting habitat and indirectly by influencing

Michigan Natural Features Inventory P.O. Box 30444 - Lansing, MI 48909-7944 Phone: 517-373-1552 short-eared owl, Page 3

Dechant, J.A.. M.L. Sondreal, D.H. Johnson, L.D. Igl, Sample, D.W., and M.J. Mossman. 1997. Managing C.M. Goldade, M.P. Nenneman, and B.R. Euliss. habitat for grassland birds in Wisconsin. Bureau of 1998 (revised 2000). Effects of management Integrated Science Services, Wisconsin Department practices on grassland birds: Short-eared owl. of Natural Resources, Madison, WI. 154 pp. Northern Prairie Wildlife Research Center, Jamestown, ND. 10 pp. Zimmerman, D.A., and J. Van Tyne. 1959. A distribu- tional check-list of the birds of Michigan. Univer- Evers, D.C. 1991. “Short-eared owl”. In: Atlas of sity of Michigan Museum of Zoology. Paper No. Breeding Birds in Michigan. Brewer, R., G. A. 608. Mcpeek, and R.J. Adams, Jr (eds). 1991. Michigan State University Press, East Lansing, 590 pp. Abstract citation: Cooper, J.L. 2000. Special animal abstract for Asio Evers, D.C., ed. 1994. Endangered and Threatened flammeus (short-eared owl). Michigan Natural Wildlife of Michigan. The University of Michigan Features Inventory, Lansing, MI. 3pp. Press, Ann Arbor, MI. 412 pp.

Herkert, J.R., S.A. Simpson, R.L. Westemeier, T.L. Esker, and J.W. Walk. 1999. Response of northern harriers and short-eared owls to grassland management in Illinois. Journal of Wildlife Management 63:517-523.

Holt, D.W. and S.M. Leasure. 1993. Short-eared owl (Asio flammeus). In: The Birds of North America, No. 62. (A. Poole and F. Gill, eds.). Philadelphia: The Academy of Natural Sciences: Washington D.C.: The American Ornithologists’ Union.

Johnsgard, P.A. 1988. North American Owls. Washington D.C., Smithsonian Institution Press, 295 pp.

Johnson, D.H. 1996. Management of northern prairies and wetlands for the conservation of neotropical migratory birds. Pages 53-67, in: Management of mid-westerm landscapes for the conservation of Neotropical migratory birds. U.S.D.A. Forest Service General Technical Report NC-187.

Kinziger, A. 1997. Winter roost habitat and diet of short-eared owls (Asio flammeus) in Door County, Wisconsin. The Passenger Pigeon, Vol. 59, No. 1. Updated September 2000

Natural Heritage Biological and Conservation Data Copyright 2004 Michigan State University Board of Trustees. System. 1999. Consolidated by the Michigan Michigan State University Extension is an affirmative-action, Natural Features Inventory, Lansing, MI. equal-opportunity organization. Funding for abstract provided by Michigan Department of Natural Resources-Forest Management Division and Wildlife Division.

Michigan Natural Features Inventory P.O. Box 30444 - Lansing, MI 48909-7944 Phone: 517-373-1552