Recovery Strategy for Lake Sturgeon in Ontario hosts of sea lamprey. However, reduced utilization of lampricides may have serious implications for other fish such as salmonid species in the Great Lakes. Direct predation on Lake Sturgeon eggs by fish and invertebrates has been documented by several authors (Kempinger 1988; Nichols et al 2003; Caroffino et al. 2010). The spread of invasive fish (e.g., Round Goby, Neogobius melanostomus) and invertebrate (e.g., Rusty Crayfish, Orconectes rusticus) species to waters inhabited by Lake Sturgeon represents a threat to egg survival. Climate Change As our climate changes, predictive models suggest that temperatures will become warmer, water levels may decrease and current hydrological patterns may be altered. Disruption of the timing of peak flows due to variability in temperature and changes to ice cover, the timing and magnitude of precipitation events, may disrupt the timing of spawning and hatching events, result in habitat loss and create barriers between critical habitats (e.g., overwintering and spawning locations). In natural systems, Lake Sturgeon may be capable of adapting to changing environmental conditions, as they have done for millions of years. In developed systems, decreasing water levels may result in greater demands on water budgets from existing users and fish species. Dredging activities may be required, where navigation becomes an issue, resulting in the loss of nursery habitat (e.g., at the mouths of rivers), increased turbidity during dredging activities and loss of benthic food sources.
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Knowledge Gaps
The following knowledge gaps exist with respect to Lake Sturgeon biology and impacts of threats on Lake Sturgeon populations: Information Management the current status of remnant Lake Sturgeon sub-populations across Ontario and their distribution in remote areas of northeastern and northwestern Ontario; the locations of important habitat features including staging, spawning, nursery, and overwintering areas. It is recognized that much of this information may exist within First Nation communities in the form of ATK; identification of factors impeding recovery in drainages and in localized portions of drainages where Lake Sturgeon abundance is believed to be declining; risk assessments to determine where Lake Sturgeon are or may be potentially at risk due to existing and future threats (e.g., instream development); and an inventory of existing water control structures to identify which facilities can be decommissioned/removed in order to benefit Lake Sturgeon recovery. Research and Assessment larval, young-of-the-year and yearling habitat preferences and the factors that contribute to habitat suitability;
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