Marine Biology

, Volume 149, Issue 2, pp 401–413 | Cite as

Medium-term impacts of hydraulic clam dredgers on a macrobenthic community of the Adriatic Sea (Italy)

  • Elisabetta B. MorelloEmail author
  • Carlo Froglia
  • R. James A. Atkinson
  • P. Geoffrey Moore
Research Article


Hydraulic dredging targeting the bivalve Chamelea gallina in the northern and central Adriatic Sea has been taking place for over 30 years. In the period 2000–2001, 73 commercial dredgers harvested the resource within the sandy coastal area of the Ancona Maritime District (central Adriatic Sea). Despite this, no study aimed at investigating the impact of the fishery on the macrobenthic community of the area has ever been carried out. Sampling was done at 6 monthly intervals in an attempt to relate the impact of hydraulic dredging to different levels of fishing intensity. Data regarding two depth strata (4–6; 7–10 m) were analysed separately by means of permutational multivariate analysis of variance. The results revealed an overall condition of moderate disturbance within the benthic community, especially so within the 4–6 m depth stratum. The response of the benthic community to varying intensities of fishing activity was rapid, occurring within 6 months. Differences in the response of benthic community to differing intensities of fishing activity were found between the two depth strata considered. Significant differences in multivariate location of the benthic community were revealed between the three disturbance levels in both depth strata. Differences in multivariate dispersion were detected above a threshold level of fishing intensity, only within the shallow community. Differences were found between depth strata relating to species diversity and evenness, with significant differences between levels of fishing intensity being evident only within the 4–6 m depth stratum. The results emphasised that, even in a benthic community that is typical of a moderately disturbed environment, the effects of fishing on community structure were still discernible over and above the natural variation.


Fishing Benthic Community Hermit Crab Fishing Activity Macrobenthic Community 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors would like to thank the skipper and crew of the commercial hydraulic dredger employed to carry out the field work and Mr Bruno Antolini, for their invaluable work at sea; Dr. Aniello Russo for providing wavemeter data, and Dr. Enrico Arneri and two anonymous referees for improving earlier drafts of the manuscript. This study was funded under contract to the European Commission as a Study Project of the Common Fisheries Policy (no. 99/078). This paper does not necessarily reflect the views of the European Commission and in no way anticipates any future opinion of the Commission.


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Elisabetta B. Morello
    • 1
    Email author
  • Carlo Froglia
    • 1
  • R. James A. Atkinson
    • 2
  • P. Geoffrey Moore
    • 2
  1. 1.CNR—Istituto di Scienze MarineSezione Pesca MarittimaAnconaItaly
  2. 2.University Marine Biological Station MillportScotlandUK

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