Habitat suitability modeling based on a spatio-temporal model: an example for Cusk in the Gulf of Maine

Habitat use and distribution is a critical aspect in the management and conservation of a species, particularly for those in decline. Habitat suitability indices (HSI) are a common method of habitat mapping dependent on empirical data that can easily lead to misunderstanding the spatio-temporal dynamics of marine species experiencing population decline and density-dependent catchability within surveys. This is especially true when only a single monitoring program with limited spatio-temporal coverage is used. A delta-GLMM was used to combine trawl and longline surveys to predict density estimates for Cusk (Brosme brosme) in un-sampled locations for use in HSIs. Catchability was estimated for longline and trawl gear without having an estimate of area fished for the longline survey. HSIs performed better using model-based density estimates from multiple surveys compared to sample-based abundance indices from a single survey. The increased spatial resolution can better inform the HSIs by providing informatio...