Observations on the biology of pandalus montagui [Crustacea: Decapoda]

Abstract

An account is given of the populations of P. montagui occurring off the Northumberland coast at depths ranging from 20 to 50 fm. Sampling, which extended from 1954 to 1961, shows that the population in 20–30 fm is composed predominantly of o-group males and females and smaller numbers of 1-group females while that in 50 fm is composed predominantly of 1 and 2 group males and females. This difference can be explained in terms of sex change and migration.Eggs laid in the period from the last week in November to the first week in January hatch by the end of April. Growth of the new year-group is so rapid that they mature in time for the next breeding season. Egg numbers vary from 200 to 3000.It can be calculated that the number of larvae hatched out inshore exceeds that offshore by 15 times, but many of the larvae produced by the deep-water.