Fish faunal and habitat analyses using trawls, camera sleds and submersibles in benthic deep-sea habitats off central California

Beam trawl, camera sled and submersible data from 2 000-3 300 m off central California produced similar fish faunal composition, but different density estimates. All species caught in trawls were observed in camera-sled and s ubmersible observations. However, some rare species that were observed were not caught in trawls. The fish fauna was dominated by the families Macrour idae, Zoarcidae, Moridae, and Rajidae. Fishes both trawled and observed wer e the macrourids Coryphaenoides armatus, C. filifer and C. leptolepis; the zoarcids Bothrocara spp., Pachycara lepinium and Lycenchelys spp.; the mori d Antimora microlepis; the rajid Bathyraja trachura, the ophidiid Spectrunc ulus grandis, and the liparidid Careproctus ovigerum. One unidentified lipa ridid (Paraliparis sp.) and two unidentified Lycenchelys spp. were trawled and may have been seen but also could not be identified to species from pho tographs. Observed only in photographs were the liparidids Paraliparis rosa ceus and Careproctus melanurus, synodontid Bathysaurus mollis, and noto-can thid Notacanthus chemnitzii. These three techniques differed in their abili ty to provide specimens for accurate identification, counts, and later life history (feeding habit, age and growth, and reproduction) studies, and to provide information on dispersion, habitat utilization, behavior and intera ctions. Accurate density estimates were undoubtedly hampered by trawl and c amera sled avoidance, escape, and uncertainties concerning the area trawled . Camera sleds produced higher (and perhaps better) estimates of density. S ubmersible observations from the DSV Alvin produced a similar species list but little additional, quantitative information. Both visual techniques all owed habitat characterization, but no strong faunal associations with habit at types were observed. (C) 1999 Ifremer / CNRS / IRD / Editions scientifiq ues et medicales Elsevier SAS.