Effects of bottom fishing on the benthic megafauna of Georges Bank

• Published in: Marine Ecology Progress Series
• Main Authors: Collie, Jeremy S., Escanero, Galo A. A., Valentine, Page C.
• Format: Text
• Language: unknown
• Published: DigitalCommons@URI 1997
• Subjects: Benthic communities; Fishing impacts; Habitat disturbance; Scallop dredging; Northwest Atlantic
• Online Access: https://digitalcommons.uri.edu/gsofacpubs/959; https://doi.org/10.3354/meps155159

This study addresses ongoing concerns ever the effects of mobile fishing gear on benthic communities. Using side-scan sonar, bottom photographs and fishing records, we identified a set of disturbed and undisturbed sites on the gravel pavement area of northern Georges Bank in the northwest Atlantic. Replicate samples of the megofauna were collected with a 1 m Naturalists' dredge on 2 cruises in 1994. Compared with the disturbed sites, the undisturbed sites had higher numbers of organisms, biomass, species richness and species diversity; evenness was higher at the disturbed sites. Undisturbed sites were characterized by an abundance of bushy epifaunal taxa (bryozoans, hydroids, worm tubes) that provide a complex habitat for shrimps, polychaetes, brittle stars, mussels and small fish. Disturbed sites were dominated by larger, hard-shelled molluscs, and scavenging crabs and echinoderms. Many of the megafaunal species in our samples have also been identified in stomach contents of demersal fish on Georges Bank; the abundances of at feast some of these species were reduced at the disturbed sites.