Scientia Marina (Dec 2019)

Large-scale distribution of a deep-sea megafauna community along Mediterranean trawlable grounds

  • Ulla Fernandez-Arcaya,
  • Isabella Bitetto,
  • Antonio Esteban,
  • M. Teresa Farriols,
  • Cristina García-Ruiz,
  • Luis Gil de Sola,
  • Beatriz Guijarro,
  • Angélique Jadaud,
  • Stefanos Kavadas,
  • Giuseppe Lembo,
  • Giacomo Milisenda,
  • Irida Maina,
  • Slavica Petovic,
  • Letizia Sion,
  • Sandrine Vaz,
  • Enric Massutí

DOI
https://doi.org/10.3989/scimar.04852.14A
Journal volume & issue
Vol. 83, no. S1
pp. 175 – 187

Abstract

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The large-scale distribution pattern of megafauna communities along the Mediterranean middle slope was explored. The study was conducted between 500 and 800 m depth where deep-water fishery occurs. Although community studies carried out deeper than 500 m are partly available for some geographic areas, few large-scale comparative studies have been carried out. Within the framework of the MEDITS survey programme, we compared the megafauna community structure in ten geographical sub-areas (GSAs) along the Mediterranean coasts. Additionally, the spatial distribution of fishing was analysed using vessel monitoring by satellite information. Overall, the community showed a significant difference between sub-areas, with a decreasing eastward pattern in abundance and biomass. Longitude was the main factor explaining variation among sub-areas (by generalized additive models). However, we found a region which did not follow the general pattern. GSA 6 (northern Spain) showed significantly lower abundance and a different composition structure to the adjacent areas. The decrease in community descriptors (i.e. abundance and biomass) in this area is probably a symptom of population changes induced by intense fishery exploitation. Overall, a combination of environmental variables and human-induced impacts appears to influence the bentho-pelagic communities along the slope areas of the Mediterranean.

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