Recovery Strategy for Lake Sturgeon in Ontario
Endangered: A species facing imminent extinction or extirpation. Endangered Species Act, 2007 (ESA): The provincial legislation that provides protection to species at risk in Ontario. Extant: A species or population that still exists within a particular area or known range. Extirpation: The elimination of a species or subspecies from a particular area but not from its entire range. Fluvial: A term to refer to the physical processes associated with rivers and streams and the deposits and landforms created by them. Great Lakes Fishery Commission (GLFC): The Great Lakes Fishery Commission was established in 1955 by the Canadian/United States Convention on Great Lakes Fisheries. The commission coordinates fisheries research, controls the invasive sea lamprey and facilitates cooperative fishery management among the state, provincial, tribal, and federal management agencies. High water mark: The usual or average level to which a body of water rises at its highest point and remains for sufficient time so as to change the characteristics of the land. In flowing waters (rivers, streams) this refers to the “active channel/bank-full level� which is often the 1:2 year flood flow return level. In inland lakes, wetlands or marine environments it refers to those parts of the waterbody bed and banks that are frequently flooded by water so as to leave a mark on the land and where the natural vegetation changes from predominately aquatic vegetation to terrestrial vegetation (excepting water tolerant species). For reservoirs this refers to normal high operating levels (Full Supply Level). For the Great Lakes this refers to the 80th percentile elevation above chart datum as described in DFO’s Fish Habitat and Determining the High Water Mark on Lakes (DFO 2007 ). Larval drift: A period of time within which newly hatched Lake Sturgeon rise from the substrate and drift downstream from the spawning and incubation areas via currents while still absorbing their yolk sac. Heterocercal tail: In fish, a tail in which the tip of the vertebral column turns upward, extending into the dorsal lobe of the tail fin; the dorsal lobe is often larger than the ventral lobe. The heterocercal tail is present in many fossil fish, in the sharks (Chondrichthyes), and in the more primitive bony fish (e.g., the families Acipenseridae and Polyodontidae). Invasive species: Plants, animals, aquatic life and micro-organisms that compete with and dominate native species when introduced outside of their natural environment.
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