Habitat Preference of Skates in the NW Atlantic

Increasingly targeted by commercial fisheries, the seven resident northwest Atlantic species of skates possess life history traits that make them vulnerable to overexploitation, such as slow growth, late maturation and low fecundity. The various species occupy overlapping habitats and often migrate long distances. While their ecological role as benthic marine generalists and geographic ranges are understood, little is known about how they utilize available habitat. We statistically analyzed skate habitat preference using data collected by the NMFS bottom trawl survey for 1963-2009. Utilizing the nonparametric cumulative distribution approach of Perry and Smith (1994), we compared available and occupied habitat for each species. Significant associations were found for environmental variables temperature, salinity and depth. Species specific habitat associations were estimated with emphasis on temporal variations. We discuss the implications of habitat preference for range overlap and inter-specific competition. This study provides valuable insights into the spatial and temporal habitat use of skates and improves scientific understanding of skate ecology.