Evaluating egg mats as a method for identifying white sturgeon spawning habitat characteristics

Recovering species at risk requires careful consideration of their biology to identify the environmental needs that underpin restoration efforts. Endangered Nechako white sturgeon's recovery is faltering due to ongoing recruitment failure in early life stages, thus developing our understanding can help define the underlying mechanisms behind it. This study sought to evaluate egg mats as a way of identifying white sturgeon spawning habitat characteristics through use of experimentation and modeling techniques. The experiment revealed how the number of embryos on an egg mat relates to where sturgeon spawned. These parameters informed generalized additive models fit to simulated egg mat data, which determined whether spawning site characteristics can be identified using historic egg mat data. This study outlines the deposition rate of embryos on egg mats, and demonstrates that egg mat data alone is not enough to establish what environmental variables influence fine-scale sturgeon spawning site selection.