NCCOS Assessment: Groundfish biodiversity hotspots off the Pacific Coast of Oregon from 1971-09-05 to 2010-09-20 (NCEI Accession 0156467)

This data set comprises maps of predicted long-term groundfish biodiversity hotspot probabilities off the Pacific Coast of Oregon. Predicted hotspot probabilities are given for four biodiversity indices: 1) relative abundance, 2) relative biomass, and 3) species number for all groundfishes, and 4) relative abundance for only nearshore groundfishes. The nearshore species assemblage includes: Sand Sole, English Sole, Pacific Sanddab, Speckled Sanddab, Petrale Sole, Starry Flounder, and Butter Sole. Hotspots were defined as areas with predictions in the top 10% of values of at-sea observations.

Areas of relatively high biodiversity were predicted using at-sea groundfish observations collected from 1971 to 2010 and associative models linking species observations with environmental covariates. Groundfish observations were taken from existing fishery-independent trawl data collected by NOAA’s National Marine Fisheries Service and flatfish trawl data collected by the Oregon Department of Fish and Wildlife. Environmental predictors included position on the shelf, sea floor habitat, depth, slope, aspect, slope of slope, and oceanographic productivity were used to predict areas with relatively high groundfish biodiversity. Binary logistic regression trees were used to associate species observations with environmental covariates and predict categorical results (Hotspot/Low classes). Mapped values indicate the probability of a raster cell belonging in the hotspot class.