§ Norman Baker
To ask the Secretary of State for Environment, Food and Rural Affairs what estimate she has made of the percentage of(a) plaice, (b) cod, (c) dab, (d) flounder, (e) herring, (f) haddock, (g) skate and (h) huss (i) landed in British ports and (ii) in the North Sea which are diseased. 
§ Mr. Bradshaw
Fish with obvious signs of disease are not generally landed because they would not be marketable. Data on landings of diseased fish are therefore not collected. However, any unusual disease trends in fish catches and landings would be noticed by the industry and reported to Defra via the Sea Fisheries Inspectorate.
Defra undertakes a regular programme of disease surveillance of fish stocks in the North Sea, although sample sites may not necessarily be in areas of commercial fishing activity. The work is carried out by the CEFAS, Weymouth Laboratory and the programme follows standardised methodologies, which have been agreed internationally by the International Council for the Exploration of the Seas (ICES) for sampling and reporting fish diseases.
The percentage of cod, plaice, herring, haddock and flounder with obvious disease signs is very low, usually less than 1 per cent. Dab are unusually susceptible to diseases and in localised areas the prevalence may be up to 10–20 per cent. with lower levels in the northern North Sea. Up to 40 per cent. of dab in some areas such as West Dogger Bank exhibit abnormal pigmentation but it is not known whether this is indicative of disease as no causative agent has been sound. Studies are also being carried out on liver nodules (tumours) in dab and these indicate that the condition is present in fish in most areas but with a higher incidence of up to 14 per cent. at Flamborough and West Dogger. Insufficient number of skate and huss are caught during the monitoring programme to allow meaningful disease assessment to be made.1928W