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Offshore wind farms are proposed around the coast of the UK and elsewhere in Europe. These sites tend to be located in shallow coastal waters that often coincide with areas used by over-wintering Common Scoter Melanitta nigra. A large-scale study was undertaken to ascertain the relationship of the spatial distribution of Common Scoter in Liverpool Bay with prey abundance and environmental and anthropogenic variables that may affect foraging efficiency. The highest numbers of Common Scoter coincided with sites that had a high abundance and biomass of bivalve prey species. There was strong evidence that the maximum observed biomass of bivalves occurred at a mean depth of c. 14 m off the Lancashire coast and at c. 8 m off the north Wales coast. This coincided well with the distribution of Common Scoter at Shell Flat, but less well with the distribution of birds off North Wales. Common Scoters were observed in lowest numbers or were absent from areas in which anthropogenic disturbance (shipping activity) was relatively intense, even when these areas held a high prey biomass. Commercial fishing activities did not appear to contribute to this disturbance

Offshore wind farms are proposed around the coast of the UK and elsewhere in Europe. These sites tend to be located in shallow coastal waters that often coincide with areas used by over-wintering Common Scoter Melanitta nigra. A large-scale study was undertaken to ascertain the relationship of the spatial distribution of Common Scoter in Liverpool Bay with prey abundance and environmental and anthropogenic variables that may affect foraging efficiency. The highest numbers of Common Scoter coincided with sites that had a high abundance and biomass of bivalve prey species. There was strong evidence that the maximum observed biomass of bivalves occurred at a mean depth of c. 14 m off the Lancashire coast and at c. 8 m off the north Wales coast. This coincided well with the distribution of Common Scoter at Shell Flat, but less well with the distribution of birds off North Wales. Common Scoters were observed in lowest numbers or were absent from areas in which anthropogenic disturbance (shipping activity) was relatively intense, even when these areas held a high prey biomass. Commercial fishing activities did not appear to contribute to this disturbance

Patches of a very dense tube mat biotope were found during fish habitat studies in the eastern English Channel. At three locations in the lows between linear sand banks off the French coast an un-described small Chaetopterus sp. occurred with small Lanice conchilega as an enriched sediment stabilizing biotope. This biotope was distinct though having similarities to other tide swept sub-tidal biotopes dominated by L. conchilega. Using cameras and side-scan sonar it was seen to overlay heterogeneous cobbles and shell hash with intermittent rippled sand veneer. The patchiness of this enriching biogenic feature contributed to the variability in trawl catches of fish.

Patches of a very dense tube mat biotope were found during fish habitat studies in the eastern English Channel. At three locations in the lows between linear sand banks off the French coast an un-described small Chaetopterus sp. occurred with small Lanice conchilega as an enriched sediment stabilizing biotope. This biotope was distinct though having similarities to other tide swept sub-tidal biotopes dominated by L. conchilega. Using cameras and side-scan sonar it was seen to overlay heterogeneous cobbles and shell hash with intermittent rippled sand veneer. The patchiness of this enriching biogenic feature contributed to the variability in trawl catches of fish.

A habitat specific survey of the epifauna and fish fauna of sandbanks off the Welsh coastline was undertaken in 2001. Of these,three sandbanks were considered to represent extensions of shallow nearshore soft-sediment communities, while a further sixsandbanks were considered to be distinct sandbanks; seabed features clearly defined in comparison with surrounding sediments.Multivariate community analyses revealed that the distinct sandbanks had both fish and epifaunal assemblages that were distinctfrom those sandbanks considered to be extensions of nearshore sediments. The distinct sandbanks were typified by low speciesdiversity and shared indicator species such as the weever fish Echiichthys vipera, the shrimp Philocheras trispinosus and the hermitcrab Pagurus bernhardus. Differences occurred in species composition among the distinct sandbanks, in particular, southernsandbanks were typified by sand sole Solea lascaris and small-eyed ray Raja microocellata. The sandbanks considered as extensionsof nearshore sediments shared many similarities with the Pleuronectes platessaLimanda limanda assemblage, identified by Ellis et al.(Estuar. Coastal Shelf Sci. 51 (2000) 299), which is widespread in the Irish Sea. Sandbanks, as a habitat definition under the EUhabitats directive, are likely to incorporate a number of physically and biologically distinct habitats of which two have beendescribed in the present study.

A habitat specific survey of the epifauna and fish fauna of sandbanks off the Welsh coastline was undertaken in 2001. Of these,three sandbanks were considered to represent extensions of shallow nearshore soft-sediment communities, while a further sixsandbanks were considered to be distinct sandbanks; seabed features clearly defined in comparison with surrounding sediments.Multivariate community analyses revealed that the distinct sandbanks had both fish and epifaunal assemblages that were distinctfrom those sandbanks considered to be extensions of nearshore sediments. The distinct sandbanks were typified by low speciesdiversity and shared indicator species such as the weever fish Echiichthys vipera, the shrimp Philocheras trispinosus and the hermitcrab Pagurus bernhardus. Differences occurred in species composition among the distinct sandbanks, in particular, southernsandbanks were typified by sand sole Solea lascaris and small-eyed ray Raja microocellata. The sandbanks considered as extensionsof nearshore sediments shared many similarities with the Pleuronectes platessaLimanda limanda assemblage, identified by Ellis et al.(Estuar. Coastal Shelf Sci. 51 (2000) 299), which is widespread in the Irish Sea. Sandbanks, as a habitat definition under the EUhabitats directive, are likely to incorporate a number of physically and biologically distinct habitats of which two have beendescribed in the present study.