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USGS · 70028350

Fishes associated with North Carolina shelf-edge hardbottoms and initial assessment of a proposed marine protected area

Abstract

Fish community data are limited from deeper shelf-edge hardbottoms along the southeastern U.S. continental shelf. This lack of data Hampers the design of recently proposed marine protected areas (MPAs) on the outer shelf of the southeastern U.S. During 2001-2004, sampling was conducted (57-25 m) to describe habitats and fish communities within and outside of the North Carolina proposed MPA (p-MPA) using the JOHNSON-SEA-LINK submersible, remotely operated vehicles, otter trawls, and hook and line. Habitats observed included soft substrate or non-hardbottom (NH), a shipwreck ("Snowy Wreck"), low relief hardbottoms (LRH), boulder fields (BF), and high relief ledges (HRL), the latter of which were divided into three mi-crohabitats. Non-metric, multi-dimensional scaling indicated that hardbottom fish assemblages were distinct from NH, and fish assemblages among microhabitats on HRL were different. In total, 152 fish species were documented. Thirty-five species were observed only on NH and 117 were observed or hardbottoms and the Snowy Wreck. Several species of anthiines were the most abundant fishes on most hardbottoms, whereas triglids, synodontids, and Seriola spp. were abundant on NH. Species richness was highest on HRL, and species composition was unique at the Snowy Wreck (238-253 m) and on BF. Future shelf-edge hardbottom research should include more standardized surveys using direct observations. Further, we recommend that the boundaries of the North Carolina p-MPA be redrawn to include more hardbottom habitat. ?? 2006 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

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A.M. Quattrini, Steve W. Ross. 2006. Fishes associated with North Carolina shelf-edge hardbottoms and initial assessment of a proposed marine protected area. https://pubs.usgs.gov/publication/70028350

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