|Effect of trawling on animals of the sea bed|
Graham, M. (1955). Effect of trawling on animals of the sea bed. Deep-Sea Research, III 3(Suppl.): 1-6
In: Deep-Sea Research, Part III. Papers in Marine Biology and Oceanography, more
Damage to fish food species trawled over in the main area of the North Sea plaice, cannot be serious; otherwise there would be a noticeable difference where trawling is impossible, as close to light vessels or among the under-water sand dunes. Direct attack, covering the ground some five or six times over on the average, did break full-grown Heart Urchins, Echinocardium cordatum, and possibly swimming or paddler crabs (Portunus depurator), but appeared not to damage Ophiura albida, nor any of the fragile-shelled plaice food animals:razor shells, Mactra or Tellina. Those forms were not very abundant, but all the 15 specimens taken of fragile animals (other than urchins and paddlers) were undamaged. Such large urchins as were damaged were not plaiCe food. Doubtless Sabellaria habitations (ross) would be broken and laid low, but they would probably soon be reconstructed. Trawling, even with a tickler chain, seems again to escape the so viable indictment.