Current ResearchersTian Everest Reasons for DeclineBurrowing owls were once a common site on the short-grass prairie regions of Canada. Sadly, the species is now nationally endangered. In the 1990’s the number of burrowing owl breeding pairs in Canada declined at a rate of over 20% per year (Skeel et al. 2001; Wellicome and Holroyd, 2001). In 2004, it was estimated that there could be anywhere from 795 to 1600 burrowing owls left in Canada (COSEWIC, 2006). The decline of burrowing owls in Canada has been attributed to habitat loss, exposure to pesticides, collisions with vehicles and predation. Habitat loss and modification are, perhaps, the most significant limiting factors on the size of the Canadian burrowing owl population. The conversion of natural grassland habitat into cropland and ranchland has resulted in a significant decrease in the amount of undisturbed habitat available for burrowing owls. In 1994, it was estimated that 61% of the mixed grass prairie in Alberta and 81% of mixed grass prairie in Saskatchewan had been converted for agricultural and urban uses (Samson and Knopf, 1994). This conversion of Canada’s grassland for human use has also caused a decrease in the number of ground-dwelling animals in the prairies. This decline has left burrowing owls with a decreasing supply of natural burrows to nest and roost in.
What We've DoneBurrowing owls disappeared from British Columbia in the 1970s. In 2004, researchers at the Centre for Conservation Research (CCR) began working with the National Burrowing Owl Recovery Team to improve the survival and return rate of burrowing owls released back into that province. These researchers examined and compared the characteristics of natural and artificial burrows in order to determine which types of nest site characteristics (location, orientation, slope, aspect, etc.) were more attractive to the owls. Conservation researchers can construct artificial burrows reasonably quickly, but it is not always certain that these burrows will be used by burrowing owls. A greater understanding of burrowing owl nest site preferences will help researchers install artificial burrows in what the owls consider ‘desirable areas’ and increase artificial burrow use. In the spring 2008, a record 120 owls were reintroduced in British Columbia’s Nicola Valley. In the spring of 2009, another 100 burrowing owls were released. To learn more about the burrowing owl click here.
References- COSEWIC (2006). COSEWIC assessment and update status report on the Burrowing Owl Athene cunicularia in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 31 pp. - Samson, F.B. and F.L. Knopf.(1994). Prairie conservation in North America. BioScience 44: 418-421. - Skeel, M.A., J. Keith, and C.S. Palaschuk. (2001). A population decline recorded by Operation Burrowing Owl in Saskatchewan. Journal of Raptor Research 35:399-407.- Wellicome, T.I. and G.L. Holroyd. (2001). The second international Burrowing Owl symposium: background and context. Journal of Raptor Research 35:269-273.
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