摘要

A visual survey technique was employed to estimate the abundance and distribution of anglerfish Lophius spp. in areas where destructive sampling methods, such as trawling, are unacceptable. To enable visual surveying at depths of over 300m, a deep towed vehicle was developed equipped with video, lights and other sensors and was towed at speeds of up to 15ms(-1) and altitudes of up to 10m (from the seabed) to survey large areas of the seabed around the Rockall Bank in the north-west Atlantic Ocean. The system allowed for areas up to 125 000m(2) to be surveyed, a substantial area comparable to that surveyed by demersal-trawl sampling. Lophius spp. densities ranged from 15 to 736 fish km(-2); these are comparable to estimated Lophius spp. densities determined by trawl surveys in adjacent areas. Estimates of Lophius spp. abundance in the closed areas ranged between 99 855 and 176 887 for the time series considered (2007-2011).

  • 出版日期2013-10

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