The Irish Naval Service on fishery protection duty off the coast of Donegal.

The Naval Vessel LÉ Grainne slips out of the north Donegal port of Rathmullen to monitor the waters for any craft involved in illegal salmon fishing.

Two Gemini dinghies are on standby ready to board any crafts involved in illegal salmon fishing.

Five hours after leaving port, the LÉ Grainne approaches Arranmore Island and a boat is spotted. A Fisheries Protection Official, accompanied by a Garda, approach a half decker but there is no crime committed this time.

Two miles further down the coast, another half-decker is boarded but again the skipper is acting within the law. The patrols continue but no culprits are found. It may be a case that the salmon fishing season has ended both in theory and in practice. 

Or maybe the complex form of bush telegraph along the Donegal mainland has warned of the Grainne's arrival.

An RTÉ News report broadcast on 23 July 1983. The reporter is Tommie Gorman.