Spotted gar (Lepisosteus oculatus) COSEWIC assessment and status report: chapter 7
Population Sizes and Trends
Fewer than 55 specimens of spotted gar have been collected in Canada (20 at Point Pelee, 27 in Rondeau Bay, two in Long Point Bay, and two in Big Creek wetland (Long Point Bay); therefore, it is not possible to identify population sizes and trends. Nineteen individuals were captured in Point Pelee National Park in 2002 and 2003, and 11 were large enough to be PIT-tagged (H. Surette, University of Guelph, pers. comm.). None of the tagged individuals were recaptured in subsequent sampling.
The fishes of Big Creek, Long Point Bay, and Rondeau Bay have been extensively sampled, primarily by seining, with few spotted gar captured. Prior to the first report in the Big Creek wetland in 2004, the wetland was sampled in four years (1979, 1983, 1984, 1985) by the Canadian Museum of Nature (CMN) and Wilfrid Laurier University (Royal Ontario Museum (ROM), unpubl. data). In 2003, it was not collected at the same Big Creek site sampled using the same effort and gear (N.E. Mandrak, unpubl. data). Long Point Bay has been sampled in 19 different years since 1928 by CMN, Ontario Ministry of Natural Resources (OMNR) and ROM (ROM, unpubl. data). In 2004, it was not collected in Long Point Bay at 30 sites intensively sampled by boat electrofishing (>1000 sec/500 m site) (N.E. Mandrak, unpubl. data). Prior to the first report in Rondeau Bay in 1955, the bay was sampled in 10 different years since 1921 by the CMN and ROM (Royal Ontario Museum, unpubl. data). In the summer of 2004, intensive boat electrofishing (>1000 sec/500 m site, i.e., more than 15 minutes surveying a 500 m stretch at each site) captured 8 spotted gar at 3 of 8 sites sampled.
The current status of populations in the Bay of Quinte and Lake St. Clair is unknown but, based on recent sampling (Bay of Quinte, 1988-2003; Lake St. Clair, 2002-2004) of suitable habitat (N.E. Mandrak, unpubl. data), they are presumed to be extirpated.
The disjunct nature of gar populations in the American portion of the lakes Erie, St. Clair and Huron (Trautman 1981, Bailey et al. 2004) and the large expanses of unsuitable habitat between American and Canadian populations make a rescue effect highly unlikely.
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