Maerl beds are mixed sediments built by a surface layer of slow-growing, unattached coralline algae that are of international conservation significance because they create areas of high biodiversity. They are patchily distributed throughout Europe (to 30 m depth around the British Isles and to 120 m depth in the Mediterranean) and many are affected by towed demersal fishing. We report the effec...

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Drainage ditches are a key conduit of nitrogen (N) from agricultural fields to surface water. The effect of ditch dredging, a common practice to improve drainage, on the fate of N in ditch effluent is not well understood. This study evaluated the effect of dredging on N transport in drainage ditches of the Delmarva Peninsula. Sediments from two ditches draining a single field were collected (0-...

The fate of released bycatch is an issue of great interest for fisheries research and management. Survival experiments were carried out to assess the survival capacity of animals damaged and discarded during clam dredging operations. Three common bycatch species, two fish (Trachinus vipera; Dicologlossa cuneata) and one crab (Polybius henslowii), were collected during the sorting of catches fro...

Global seagrass research efforts have focused on shallow coastal and estuarine seagrass populations where alarming declines have been recorded. Comparatively little is known about the dynamics of deep-water seagrasses despite evidence that they form extensive meadows in some parts of the world. Deep-water seagrasses are subject to similar anthropogenic threats as shallow meadows, particularly a...

The impact of scallop dredging on benthic megafauna was assessed by direct observation of damage, both in the bycatch and in organisms encountering dredges but not captured. Damage was assessed using a simple 4point scale adapted for different taxonomic groups. Experimental dredging was undertaken on a scallop fishing ground in the north Irish Sea, off the Isle of Man. Divers were deployed imme...

The e¡ect of dredging on bottom structure was assessed, to estimate the damage in£icted on the benthic macrofauna left on the dredge path and to evaluate aggregations of scavengers within the track. Sediment suspended during dredging rapidly resettled both on sand and sandy-mud bottoms. Dredge tracks were deeper on sandy-mud sediments and persisted longer than in sandy sediments. The disappeara...

Numerical site-specilic chemical and biological criteria were established to assess the impact of a pilot dredging project on water quality at the New Bedlord Harbor. Massachusetts, USA, Superfund site. Because most existing chemical concentrations in the water column and indigenous biota exceeded federal and state water quality limits, the derivation of site-specific criteria was required. Pri...