NACA Projects - Cormorant Predation

Operation Black Duck

Anglers and/or readers of the national angling press will be aware that the problem of fish predation by cormorants is seen to have sharply increased over recent years. The area adjoining the Thames Estuary as well as southern Essex has been particularly badly effected. Various 'theories' for the reason for the situation abound including marine pollution, the cessation of London's commercial waste dumping at sea, the reduction of the inshore fishing fleet, increased fish farming and even angling.

As usual in such circumstances there was much theory but very little 'hard' evidence.

Following a great deal of lobbying from angling interests the last government were finally persuaded to commission and fund research into the matter. The terms of reference for the research were (in retrospect) over ambitious and not specific enough.

After nearly two years delay the research report was published. It was certainly voluminous although doubtfully conclusive.

One of the aspects that the research had however identified was that cormorants were very adaptable to differing environments and had the capability to travel long distances (Birds which had nested in Wales were found in Nofolk).

This became evident in the perception of an increasing cormorant problem in Norfolk. The problem was most extreme on commercial fish farms and intensively managed fisheries. Perhaps, not surprisingly, the cormorants had made such venues their first targets. Nonetheless, there appeared to be an increasing problem on rivers; particularly during winters when nearby gravel lakes froze over.

NACA decided to become involved.

Meetings were held with RSPB to ascertain whether they saw the matter as a problem. While they agreed that there was some evidence to suggest an increase in the population of inland birds they saw no 'evidence' that this constituted a problem. Undoubtedly the 'P' in the RSPB left them with a problem to their membership in being seen to be a party to reducing cormorants numbers. Some of their members felt that there were similar problems with the control of hawks and corvids which made the politics of being part of any cormorant control even more difficult. NACA concluded that the RSPB would be unlikely to acknowledge the problem.

The situation was further exacerbated for fishery owners by the fact the cormorants had been afforded protection under the Wildlife and Country side Act 1981. In practice this meant that it seemed to be near impossible to obtain licences ( required under the Act) to control cormorants, especially in the face of MAFF's suggested "protection measures" which included fireworks (not of the .22 calibre!) and instant blow-up plastic dolls!

The Association was conscious of the need for an independent assessment of the facts. However accurate evidence might be from anglers it was agree that the birdwatching fraternity would view it with suspicion.

NACA then entered into discussions with the British Trust for Ornithology ( BTO ) at Thetford. BTO had been one of several scientific bodies involved in the original government sponsored research. They had a substantial amount of data, not all of which had appeared in the report. From talks involving the Environment Agency, NACA and the BTO it emerged that there might be considerable merit in confining research to a specific area where the activities of flocks of cormorants might be more objectively recorded.

The EA having spent considerable time and money improving Norfolk river habitats were also keen to identify fishery management systems which would help control the problem. An agreement was reached to fund research by the BTO in the Wensum valley. NACA entered into a funding partnership with the EA and the research is currently proceeding. It is hoped that a report will be forthcoming by the summer of 2001.

'Black Duck'

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