Telemetry experiments with Atlantic cod, Gadhus morhua.

Behavioural studies will be performed with Atlantic cod. This will involve baiting acoustic tags for the voluntary uptake of the tag by the fish for tracking purposes. Different sized tags and baits will be used to optimise the ingestion of the tag by the fish and the length of residency inside the stomach of the fish before it is regurgitated will be measured.Previous studies similar to that proposed here have been performed in Canada (Winger et al., 1992. Hydrobiologia 483:287-292), which caused no reported harm to the fish. Therefore, no harm or pain to the fish is expected. The experiments performed will be in flow-through seawater tanks and the seawater conditions will be monitoring daily to ensure optimum conditions for the fish. Handling will be reduced to a minimum to reduce stress. The experiments will provide important information for use in field telemetry surveys to measure the length of time deep water fish are resident at offshore oil and gas platforms.The number of Atlantic cod used for the laboratory experiments will be approximately 30 fish and maximum of 50 fish. The minimum number of fish will be used to obtain information on the optimum baited tag for uptake and the time before the tag is regurgitated by the fish.