The Wash, east coast of England

Zooplankton and zoobenthos morphological parameters; Zoobenthos taxonomic abundance; Zoobenthos taxonomy-related counts; Zooplankton and zoobenthos development stage parameters

Benthos samplers; rock dredges

The beds were surveyed on foot by 2 man teams, landed by dinghy. Total biomass was estimated by the product of: Total bed area x mean percentage mussel cover x mean biomass of mussels per square metre. The total bed area was estimated by plotting position fixes taken around the outer edge using bearing compasses or electronic navigators. Percentage cover of mussel mounds was estimated by 100m random zig-zag transects across the bed recording by 'clicker counters' the number of paces on and off mounds. At the end of each transect leg a weighed sample of mussels was taken using a 0.1 square metre quadrat and rake. The percentage of dead shell and other debris in the sample was estimated by eye. A minimum of 8 quadrat samples were retained from each bed to enable the estimates of debris to be calibrated. The mussels in these retained samples were measured to establish the size structure of mussels on the bed.

Walker, P. and Nicholson, M.D. (1986) The precision of estimates of mussel biomass by zig-zag survey., ICES CM 1986/K:6

Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory
Pakefield Road
Lowestoft
Suffolk
NR33 OHT
United Kingdom