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Abstract
Monitoring of Burrowing Owl (
Speotyto cunicularia) populations in Manitoba from 1987-1996 revealed a continuous population decline from 34 known nesting pairs to only one. Management activities are discussed including public awareness programs, reintroductions, habitat protection and provision of artificial nest burrows. Nest reuse in consecutive years ranged from 7 percent for 57 failed nests to 23 percent for 122 successful nests. Only 14 percent of unsuccessful territories were reused compared to 51 percent of successful sites. Higher nest reoccupancy rates were noted for artificial burrows (44 percent; n=27) than for natural nests (13 percent; n=152). Low return rates of banded juveniles (3.5 percent; n=538) and adults (32.7 percent; n=165) suggest that reduced survivorship may be a contributing factor to observed declines. Adult males returned more frequently (40.2 percent) than females (24.4 percent). Males were more frequently re-encountered at the same nest (51 percent) or within 1 km (94 percent) than females (33 percent and 56 percent, respectively). Average dispersal distances between years were 3.0 km for adult males (n=35) and 10.9 km for adult females (n=18). Average dispersal distances for juveniles ranged from 1-77 km, averaging 29.5 km for 9 males and 33.7 km for 9 females. Average brood size (5.1 yg/pr) and overall productivity (3.4 yg/nesting pr) appeared adequate for population maintenance.
Parent Publication
Citation
De Smet, Ken D. 1997. Burrowing Owl (
Speotyto cunicularia) monitoring and management activities in Manitoba, 1987-1996. In: Duncan, James R.; Johnson, David H.; Nicholls, Thomas H., eds. Biology and conservation of owls of the Northern Hemisphere: 2nd International symposium. Gen. Tech. Rep. NC-190. St. Paul, MN: U.S. Dept. of Agriculture, Forest Service, North Central Forest Experiment Station. 123-130.
