Blue Racer
Features: The Blue Racer (Coluber constrictor foxii) is a large, 1.5 metre long snake, named both for its speed and distinctive greyish-blue or blue green colour. Its preferred habitat is long grass prairie, savanna, alvar and open woodlands, but it also lives in rough pasture and regenerating fields of farms. Hayfields ensure a plentiful supply of rodent prey, while hedgerows and old stone walls provide cover and den sites, respectively. In winter, the Blue Racer hibernates below the frost line in rock formations and quarries.
Status: Endangered Provincially and Nationally
Threats: Modern "clean farming" practices have reduced potential habitat for Blue Racers in much of southwestern Ontario. Current threats include habitat degradation, loss of over wintering sites, human persecution, and mortality attributable to vehicles as snakes attempt to cross roads.
DISTRIBUTION:
Global range The historical distribution of the blue racer lies immediately south of the Great Lakes from southeastern Minnesota and Iowa east to Ohio and north to extreme southwestern Ontario . Ohio, Indiana, Illinois, Michigan, Wisconsin and Iowa are now the only states with extant populations of blue racers (Harding 1997). The Blue Racer is considered relatively common in parts of its United States range, but it has declined significantly in much of the Midwest.
Canadian range Coluber constrictor foxii currently occurs only on Pelee Island in Canada . Although formerly present in Pelee and Pinery Provincial Parks in extreme southwestern Ontario, the blue racer is almost certainly extirpated from these mainland sites, despite these being protected areas. The last reliable record of the blue racer in mainland Ontario was 1983 (Campbell & Perrin 1991). On Pelee Island, the species is restricted to the eastern two thirds of the island .
Population Size: At the conclusion of an intensive 3-year sampling period from 1993 to 1995, the size of Pelee Island's blue racer population was estimated via mark-recapture techniques to be 205 adults (Porchuk 1996; as reported in the 1997 version of the status report). Population parameters estimated by both Triple-Catch and Peterson methods indicated a monotonic decline in the adult population over the 3-year period. From the conclusion of the 1995 field season to the 2000 field season, monitoring of the blue racer population via mark-recapture has been sporadic (see Table 1 for a summary of blue racer research on Pelee Island). Consequently, more recent population estimates are not available. It is anticipated, however, that an updated estimate will be derived from the fieldwork to be conducted in the spring of 2002. Systematic surveys along standardized transects and within defined areas were conducted from roughly 13 April to 12 May in the springs of 2000 and 2001 (see Willson 2000 for methodology used). Four areas that were historically known to harbour blue racers were rigorously searched during this period (see Figure 3 for survey areas). Since 1992, research teams working on Pelee Island have marked approximately 320 juvenile and adult blue racers
LIMITING FACTORS AND THREATS: The loss of suitable nesting and hibernating sites, incidental mortality on roads, and killing of the snakes by humans remain the primary threats facing blue racers on Pelee Island. Despite the precarious state of the blue racer in Canada, the identification critical habitat via intensive field effort, and the legislated protection of that habitat under Ontario's Endangered Species Act (ESA), individuals and organizations are currently proposing developments that must be considered detrimental to the species’ persistence on Pelee Island. Continued loss of nesting habitat via cottage construction along the eastern shoreline is probably one of the most significant threats, as little habitat will remain once all of the private lots have been developed (many have already been marked off and are awaiting construction). Evidence suggests that vehicular traffic will continue to increase on the island in conjunction with the growing tourist industry; thus, increased impacts of road mortality seem inevitable. Finally, recent events on Pelee Island (1998-2001) have resulted in significant levels of animosity between those studying the island's rare snakes and those wishing to further the island's economy through more intensive and destructive land uses.
Current Status & Protections:
The blue racer is currently listed as Endangered under the Ontario Endangered Species Act, 2007 and Endangered under the federal Species at Risk Act. The species has also been designated as a Specially Protected Reptile under the Ontario Fish and Wildlife Conservation Act. These acts offer protection to individuals and their habitat. The habitat of this species is further protected in Ontario by the Provincial Policy Statement under the Planning Act. The International Union for Conservation of Nature lists the global status of the blue racer as Least Concern. The species’ status was last confirmed in January 2010. Additional detail about legal protection for species at risk in Ontario is available on our Legal Protection page.
Learn more about reptile and amphibian conservation and what you can do to help these species on our Reptile and Amphibian Stewardship page.
Status: Endangered Provincially and Nationally
Threats: Modern "clean farming" practices have reduced potential habitat for Blue Racers in much of southwestern Ontario. Current threats include habitat degradation, loss of over wintering sites, human persecution, and mortality attributable to vehicles as snakes attempt to cross roads.
DISTRIBUTION:
Global range The historical distribution of the blue racer lies immediately south of the Great Lakes from southeastern Minnesota and Iowa east to Ohio and north to extreme southwestern Ontario . Ohio, Indiana, Illinois, Michigan, Wisconsin and Iowa are now the only states with extant populations of blue racers (Harding 1997). The Blue Racer is considered relatively common in parts of its United States range, but it has declined significantly in much of the Midwest.
Canadian range Coluber constrictor foxii currently occurs only on Pelee Island in Canada . Although formerly present in Pelee and Pinery Provincial Parks in extreme southwestern Ontario, the blue racer is almost certainly extirpated from these mainland sites, despite these being protected areas. The last reliable record of the blue racer in mainland Ontario was 1983 (Campbell & Perrin 1991). On Pelee Island, the species is restricted to the eastern two thirds of the island .
Population Size: At the conclusion of an intensive 3-year sampling period from 1993 to 1995, the size of Pelee Island's blue racer population was estimated via mark-recapture techniques to be 205 adults (Porchuk 1996; as reported in the 1997 version of the status report). Population parameters estimated by both Triple-Catch and Peterson methods indicated a monotonic decline in the adult population over the 3-year period. From the conclusion of the 1995 field season to the 2000 field season, monitoring of the blue racer population via mark-recapture has been sporadic (see Table 1 for a summary of blue racer research on Pelee Island). Consequently, more recent population estimates are not available. It is anticipated, however, that an updated estimate will be derived from the fieldwork to be conducted in the spring of 2002. Systematic surveys along standardized transects and within defined areas were conducted from roughly 13 April to 12 May in the springs of 2000 and 2001 (see Willson 2000 for methodology used). Four areas that were historically known to harbour blue racers were rigorously searched during this period (see Figure 3 for survey areas). Since 1992, research teams working on Pelee Island have marked approximately 320 juvenile and adult blue racers
LIMITING FACTORS AND THREATS: The loss of suitable nesting and hibernating sites, incidental mortality on roads, and killing of the snakes by humans remain the primary threats facing blue racers on Pelee Island. Despite the precarious state of the blue racer in Canada, the identification critical habitat via intensive field effort, and the legislated protection of that habitat under Ontario's Endangered Species Act (ESA), individuals and organizations are currently proposing developments that must be considered detrimental to the species’ persistence on Pelee Island. Continued loss of nesting habitat via cottage construction along the eastern shoreline is probably one of the most significant threats, as little habitat will remain once all of the private lots have been developed (many have already been marked off and are awaiting construction). Evidence suggests that vehicular traffic will continue to increase on the island in conjunction with the growing tourist industry; thus, increased impacts of road mortality seem inevitable. Finally, recent events on Pelee Island (1998-2001) have resulted in significant levels of animosity between those studying the island's rare snakes and those wishing to further the island's economy through more intensive and destructive land uses.
Current Status & Protections:
The blue racer is currently listed as Endangered under the Ontario Endangered Species Act, 2007 and Endangered under the federal Species at Risk Act. The species has also been designated as a Specially Protected Reptile under the Ontario Fish and Wildlife Conservation Act. These acts offer protection to individuals and their habitat. The habitat of this species is further protected in Ontario by the Provincial Policy Statement under the Planning Act. The International Union for Conservation of Nature lists the global status of the blue racer as Least Concern. The species’ status was last confirmed in January 2010. Additional detail about legal protection for species at risk in Ontario is available on our Legal Protection page.
Learn more about reptile and amphibian conservation and what you can do to help these species on our Reptile and Amphibian Stewardship page.
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