|Document Type:||Journal Article|
|Title:||Using spatiotemporal species distribution models to identify temporally evolving hotspots of species co-occurrence|
|Author:||E. J. Ward, Jason E. Jannot, Yong-Woo Lee, Kotaro Ono, Andrew O. Shelton, James T. Thorson|
Identifying spatiotemporal hotspots is important for understanding basic ecological processes, but is particularly important for species at risk. A number of terrestrial and aquatic species are indirectly affected by anthropogenic impacts, simply because they tend to be associated with species that are targeted for removals. Using newly developed spatiotemporal species distribution models, we examine how the co-occurrence of two species can be modeled as a function of environmental covariates and longer term trends. The focal species in our case study (eulachon) are listed under the US Endangered Species Act, and are encountered by shrimp fisheries off the US West Coast. Results from our spatiotemporal model indicate that eulachon biomass (and bycatch) is related to depth and sea surface temperature. Additionally, there is a longer term trend of increasing eulachon biomass in the region. We examined whether this trend may be caused by increasing catch rates, or increasing population size; using an independent dataset, there appears to be support for large increases in eulachon biomass over the period 2007-2012. Based on our results, the application of spatiotemporal models to species that are of conservation concern appears promising in identifying the spatial distribution of environmental and anthropogenic risks to the population.