Salmon movements in Galway Bay in 1978 and 1979

Abstract

In 1978 tagging investigations commenced into the origin of salmon caught in drift nets in Galway Bay. This fishery began in 1969 with a catch of 355 fish and, by 1975 had increased dramatically to 33,607. However the catch declined to less than half the maximum and in 1979 was down to 15,171. There are 76 drift net licences in the Bay which incorporates two fishery districts, Galway and Connemara. The vessels used vary from 5 metre currachs to 20 metre trawlers. The majority of the boats are half deckers of between 9 and 11 metres. The fishery starts in mid-May but the bulk of the catch is taken in June and July. The main component of the catch is grilse with an average weight of 3 kg. During the period fishing is carried on over 24 hours daily except for the weekly close season time. The fishery extends from west of a straight line from Spiddal Harbour to Blackhead, Co Clare in the east , and from Slyne Head to Hag's Head, Co. Clare in the west and also incorporates the Aran Islands. Drift nets are shot at right angles to the coastline in roughly a north-south direction, all vessels staying quite close to land, the furthest distance out being 2km. The maximum length of net permitted in the area is 730 metres or 800 yards. The majority of boats fished nets of this length; however some of the smaller craft used nets as short as 300 metres. All nets are 30 meshes deep. Throughout the programme fish were tagged using Lea's hydrostatic tags described by Went (1951). As in previous tagging programmes, recovery baths were used to ensure that only the fittest fish were released after tagging.