Recovery of a population of the flame shell, Lima hians, in an Irish bay previously contaminated with TBT

The flame shell, Lima hians, is dominant in the shallows of the Moross Channel in Mulroy Bay, Co. Donegal. Its interwoven byssal threads form an extensive ‘carpet’ covering shell-sand. Laminarians attach to this ‘carpet’ and provide a canopy acting both as a substratum and shelter for several species. The population was first studied in 1980, a year prior to the use of TBT. From 1981–1985 TBT was used within Mulroy Bay as an antifoulant on salmon cages and there was a noticeable decline in the population of Lima. This led to the loss of the byssal carpet and laminarian cover and ultimately exposed the sand, which became unstable and formed waves. TBT usage was discontinued in 1985 and legally controlled in 1987. The Moross Channel was re-visited in 1994; the population has recovered and a canopy of laminarians was present as in 1980.