Publication Abstract

Mass mortality of common dolphins (Delphinus delphis) in south-west England due to incidental capture in fishing gear

Mass mortality of common dolphins (Delphinus delphis) in south-west England due to incidental capture in fishing gear

T. Kuiken, V.R. Simpson, C.R. Allchin, M. Bennett, G.A. Codd, E.A. Harris, G.J. Howes, S. Kennedy, J.K. Kirkwood, R.J. Law, N.R. Merrett and S. Phillips

In the first quarter of 1992, 118 dolphin carcasses, of which 54 were positively identified as common dolphins (Delphinus delphis), were found stranded on the coast of Cornwall and Devon. To determine the cause, detailed post mortem examinations were carried out on 38 of the carcasses, and the results were compared with those from 20 common dolphins that stranded on the coast of Cornwall and Devon in the previous 15 months. There was no evidence that the deaths were due to an infectious or parasitic disease, or acute intoxication by any of the algal toxins, trace metals or chlorinated hydrocarbons measured. However, 30 of the 38 dolphins showed signs associated with incidental capture in fishing gear. Skin lesions characteristic of capture in a small-meshed net and the predominance of recently ingested Atlantic mackerel (Scomber scombrus) and pilchard (Sardina pilchardus) in the stomachs of dolphins suggest that they had been caught in the trawl or purse seine nets used for these fish. There is insufficient information to explain why this high mortality occurred in 1992 and not in other years.

Reference:

T. Kuiken, V.R. Simpson, C.R. Allchin, M. Bennett, G.A. Codd, E.A. Harris, G.J. Howes, S. Kennedy, J.K. Kirkwood, R.J. Law, N.R. Merrett and S. Phillips, 1994. Mass mortality of common dolphins (Delphinus delphis) in south-west England due to incidental capture in fishing gear. Veterinary Record, 134: 81-89.

T. Kuiken, V.R. Simpson, C.R. Allchin*, M. Bennett, G.A. Codd, E.A. Harris, G.J. Howes, S. Kennedy, J.K. Kirkwood, R.J. Law*, N.R. Merrett and S. Phillips

Veterinary Record, 134: 81-89