Temporal and spatial variation in fecundity of Irish Sea plaice

No abstracts are to be cited without prior reference to the author.There is an increasing need to have information on the biology of stocks to understand their population dynamics. In addition, quantification of the variability in biological characteristics within a management unit (possibly due to sub-stocks) and between years is essential. Irish Sea plaice (Pleuronectes platessa) are one such stock and are currently managed as a single unit whereas there is evidence that it probably consists of at least two semi-isolated stocks. In order to model these stocks accurately greater information is needed on the inter-annual variability in reproductive dynamics in each individual stock. The current study examined the reproductive investment (fecundity) over a number of years in the Irish Sea using fish caught during the spawning season in Liverpool Bay, Cumbrian coast and the western Irish Sea. Fecundity estimates were also made during September 2003 for the three areas and in September 2004 for Liverpool Bay. This is the period in which oocyte recruitment takes place.