Bannister, R.C.A.
The clawed lobster occurs at low density in coastal waters. Shelter is important, particularly in the early benthic stages, and the main habitat is cobble, boulders, or bedrock, but also breakwaters and wrecks. Most tagged lobsters move only a few kilometres, and stocks are mainly local. Distribution and dispersal of larvae are poorly studied, and stock relationships are not well understood.
Clawed lobsters are caught commercially by baited traps, and European landings average 2400 tonnes. Stocks are generally heavily exploited, and length distribution analysis indicates that fishing mortality is often 60% or more per annum. Most lobsters are caught within one or two moult groups of the legal size (85mm carapace length, which is also close to the mean size of first maturity), and large lobsters are rare.
Although stocks are depleted, and individual fecundity is less than 50 000 eggs, recruitment has not yet failed, except in Norway, but there has been substantial interest in stock restoration using hatchery-reared juveniles. Recent experiments in UK, Norway and Ireland, show that hatchery juveniles survive in the wild long enough to reach legal size and contribute to catches and egg production. The commercial, ecological and economic justification of this approach, are still being evaluated.
(Ministry of Agriculture, Fisheries and Food, Directorate of Fisheries Research, Fisheries Laboratory, Lowestoft, Suffolk, NR33 0HT, UK)
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