Evaluating conservation concern for freshwater bycatch within a Canadian bait fishery

Quantifying the probability of bycatch from fisheries is a critical first step to assess potential risk to incidentally-captured species. Freshwater fisheries are underrepresented within bycatch literature despite economically and ecologically significant commercial fisheries throughout North American freshwaters.  Baitfish harvesting is one of many commercial fisheries prevalent within North America, yet the potential for bycatch during harvest operations remains largely unknown.  To determine the potential likelihood of incidental harvest of non-target species, a combination of indirect (e.g., spatial analysis of extensive species distribution records throughout inland harvest areas) and direct (e.g., simulated harvests incorporating the probability of detection) methods were used to quantify conditional probabilities for encountering imperiled, game, and invasive species, given the capture of legal bait species.  Bycatch estimates were compared to species composition of retail bait tanks within the study region to assess the degree of incidental bycatch removal.  Although initial bycatch estimates suggested moderate bycatch likelihood across each category, species composition within retail tanks suggested commercial harvest practices are reasonably effective at removing bycatch prior to retail sale.  Results from this study will be used to identify specific localities posing the greatest risk for encountering imperiled, game and invasive species in an effort to reduce conservation concern for freshwater bycatch.