To ask the Minister of Agriculture, Fisheries and Food what research is being carried out on the long-term effects of dredging on marine life.
The Ministry has carried out research investigations relevant to the problems posed to fish and shellfish resources by gravel extraction since the 1970s. In the vicinity of Hastings shingle bank they have comprised diving and sonar studies on the infilling of experimental pits; diver, underwater camera and remote vehicle searches for overwintering crabs and a general description of the benthos using scientific dredges. Current commercial dredging activity off Hastings and the Isle of Wight is being monitored by side scan sonar prior to future benthic studies. The importance of the eastern channel for crab spawning and potential impact of aggregate extraction is currently being asessed using plankton surveys.The Ministry is now initiating a three-year study to assess the impact of gravel extraction on marine life. The objectives will be to assess the initial impact of dredging benthos and the recovery of benthic life once dredging has ceased. The study will identify recruitment from plankton and other benthic communities in terms of the diversity of taxonomic groups present and the densities of individuals.