These areas typically provide an appropriate food supply (both quality and quantity), ideal physical conditions (temperature, salinity, etc.), and reduced biological interactions (predation, competition, etc.) for immature individuals thereby increasing survival rates compared to other habitats ( Heupel et al., 2007 Parsons et al., 2008). Shark nursery habitats are areas that can disproportionately contribute to the productivity of a population ( Beck et al., 2001 Heupel et al., 2007). Our study improves characterization of essential fish habitat for young white sharks and provides new insights into their reliance on this productive continental shelf ecosystem. These results suggest young white sharks exhibit connectivity between the immediate shoreline and mid-continental shelf region, where they play important ecological roles as predators on a variety of species. ![]() Water column temperatures during these oscillations ranged between 7.9 and 26.2☌ (mean = 19.5 ± 2.0☌) with several individuals traversing highly stratified regions presumably associated with a mid-shelf cold pool adjacent to the Hudson Shelf Valley. Vertical depth profiles illustrated oscillations between the surface and 199 m of water, with an average swimming depth of 9.2 ± 8.9 m. Multiple individuals also traversed the mid- to outer shelf region after leaving the Montauk tagging area. ![]() Log-likelihood chi-square analyses determined selection for waters with underlying bathymetry of 20–30 m, sea surface temperatures between 20.0 and 22.0☌, sea surface salinities between 31.0 and 32.0 ppt, and chlorophyll-a concentrations between 2.0 and 8.0 mg⋅m –3. Sharks exhibited horizontal movements parallel to Long Island’s southern shoreline and coastal New Jersey, with distances from 0.1 to 131.5 km from shore. Horizontal position estimates were used to extract a suite of environmental measurements via remote sensing platforms and were linked with vertical profiles to produce three-dimensional movements for a subset of individuals also fitted with pop-up satellite archival tags ( n = 7). Between 20, 21 young-of-the-year and juvenile white sharks were fitted with satellite and acoustic tags to examine distribution and selection for a suite of oceanographic variables during their late summertime (i.e., August to October) residence in the New York Bight. Recent research has confirmed a white shark ( Carcharodon carcharias) summer nursery off Long Island, New York however, habitat characterization of this nursery has not yet been conducted nor has fine-scale analysis of vertical behavior. For many species, these cross-shelf distributions can change depending on ontogeny or seasonal conditions.
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