On the biology of Crangon allmani Kinahan in Northumberland Waters

Abstract

Since November 1954, the natant epifauna in depths greater than 20 fm. off the Northumberland coast has been sampled at a number of stations with the object of obtaining information on its constitution and fluctuations. The survey has been limited to those species caught with a net of f in. mesh. Seasonal and yearly fluctuations in this fauna must have a considerable effect on the inshore fisheries, for these animals form an important part of the food of marketable fish, yet, this fauna has never beensubject to a detailed analysis over a number of years.Samples have been taken as regularly as weather and other laboratory commitments have allowed. In practice this has been of the order of one sample each month, butat times sampling has been more frequent than this (Table 8). Although sampling is being continued, the material collected so far gives much information on the epifaunaas a whole and the biology of the constituent natant Crustacea and Mollusca.