Where did all the little fish go? Minnow and related species habitat in Southern Ontario

Session: Restoration and Management of Great Lakes Fishes (2)

Jackie Cockburn, Dept. of Geography, Environment & Geomatics, University of Guelph, [email protected]
Lindsay Davis, GEO Morphix Ltd, [email protected]
Alex Scott, Dept. of Geography, Environment & Geomatics, University of Guelph, [email protected]
Paul Villard, GEO Morphix , [email protected]

Abstract

Redside Dace (Clinostomus elongates) is listed as an endangered species within the Golden Horseshoe region of southern Ontario, where the majority of the Canadian population is located. Two winter and spring field campaigns (2014-2016) evaluated Redside Dace and related small fish habitat within major watersheds of the Golden Horseshoe, including the Don River (Patterson Creek), the Humber River (West Humber River), and the Credit River (Fletcher’s Creek in Brampton, Fletcher’s Creek in Mississauga; Springbrook Creek, and Silver Creek).  In the six sites, all but two sites had positive observations of Redside Dace during at least one site visit (including non-winter visits).  The two exceptions were Patterson Creek in east Toronto, and Springbrook Creek in Brampton.  Winter observations (presence of ice, and/or air temperatures below 0°C) suggest that Redside Dace habitat is limited in these study reaches. Habitat characterization assessments (in-stream vegetation, woody debris) indicate no correlation between habitat type and winter observations, but spring observations show a high coincidence with woody debris. The presence of other baitfish and juvenile salmonids at most sites suggests hydraulic and nutrient conditions are sufficient to support a diverse aquatic community, the lack of Redside Dace suggests a struggling population and possibly extirpation.

Twitter handle of presenter
sprg_guelph