COSEWIC assessment and update status report on the Burrowing Owl in Canada
- Assessment Summary
- Executive Summary
- COSEWIC History, Mandate, Membership and Definitions
- Lists of Figures and Appendices
- Species Information
- Population Sizes and Trends
- Limiting Factors and Threats
- Special Significance of the Species
- Existing Protection or Other Status Designations
- Technical Summary
- Acknowledgements and Information Sources
- Biographical Summary of Report Writer and Authorities Contacted
- Appendix 1: Potential Aboriginal Lands where Burrowing Owls May Occur as of October 2004
Burrowing Owls have an extensive breeding range in western North America (Figure 1), with a disjunct (resident) subspecies (A. c. floridana) in Florida. There are also a number of subspecies on various Caribbean islands, as well as in South America (Clark 1997). The wintering distribution of western North American populations is poorly understood. In the northern portions of the range (including Canada), the species is migratory, while many individuals in the southern part of the range (e.g., Mexico, Texas, Oklahoma, California, Arizona, New Mexico) may remain on their breeding sites through the winter. Adult and juvenile owls banded in Alberta, Saskatchewan, and Manitoba appear to migrate south through the central Great Plains to winter from southern Texas to central Mexico (James 1992, Hjertaas et al. 1995, G. Holroyd pers. com., October 2004).
Modified from Wellicome and Holroyd 2001.
No information is available for the historical (early-1900s) range of the owl across North America, and no information is available for the distribution of the owls in Mexico in the 1970s.
In Canada, Burrowing Owls currently breed in Saskatchewan, Alberta, and the southern interior of British Columbia, occupying only about half the area occupied in the 1970s, and less than one-third of the area they occupied from 1880-1950 (Figure 2). In British Columbia, Burrowing Owls were extirpated as a breeding species in the early 1980s and the few breeding pairs that still occur there are likely the result of continued reintroductions (Dyer 1991, Leupin and Low 2001).
The 2004 distribution was based on intensive search effort. The owls’ 1970−1977 breeding range is based on Wedgwood (1978), and the 1993 range is from Wellicome and Haug (1995). The owls’ historical range (1880−1950) is based on a comprehensive literature review of written records from early explorers and naturalists (Wapple 2005), with B.C. portions updated by J. Surgenor (pers. com. 2005).
In Alberta, the species was found historically throughout the Prairie regions (Figure 2; Salt and Wilk 1958). In recent decades, the species’ range in Alberta has contracted, especially along the western and northern peripheries (Wellicome and Holroyd 2001).
The breeding range in Saskatchewan has also contracted towards the south and west (Figure 2). Burrowing Owls are still widely (but sparsely) distributed in the southern prairie areas, but they no longer breed in many former nesting areas of central (e.g. Saskatoon area; Smith 1996) and southeastern Saskatchewan (Wellicome and Holroyd 2001, unpublished data from Operation Burrowing Owl). Average colony size has also declined over the past few decades (Skeel et al. 2001).
Only one pair has been confirmed breeding in Manitoba since 1999, and no nests were documented in Manitoba in 2004 (K. De Smet, pers. com., September 2004). Burrowing Owls are officially considered Endangered in Manitoba (http://www.gov.mb.ca/conservation/wildlife/).
Although Aboriginal lands are located within the current range of the Burrowing Owl (see Appendix 1), no breeding owls were found during survey work in 2003 on the Blood, Nekaneet, Piapot, and Siksika reserves (although an old nest site was located on Siksika; T. Wellicome, unpublished data). However, in 2005, one nest was found on the Blood Reserve, and one or two were reported from Siksika.
- Date Modified: