Age, growth and population dynamics of lemon sole Microstomus kitt (Walbaum 1792) sampled off the West Coast of Ireland
Hannan, Joan F.
MetadataShow full item record
The age, growth, maturity and population dynamics of lemon sole (Microstomus kitt), captured off the west coast of Ireland (ICES division Vllb), were determined for the period November 2000 to February 2002. The maximum age recorded was 14 years. Males of the population were dominated by 4 year olds, while females were dominated by 5 year olds. Females dominated the sex ratio in the overall sample, each month sampled, at each age and from 22cm in total length onwards (when N > 20). Possible reasons for the dominance of females in the sex ratio are discussed. Three models were used to obtain the parameters of the von Bertalanfly growth equation. These were the Ford-Walford plot (Beverton and Holt 1957), the Gulland and Holt plot (1959) and the Rafail (1973) method. Results of the fitted von Bertalanffy growth curves showed that female lemon sole o f f the west coast of Ireland grew faster than males and attained a greater size. Male and female lemon sole mature from 2 years of age onwards. There is evidence in the population o f a smaller asymptotic length (L«, = 34.47cm), faster growth rate (K = 0.1955) and younger age at first maturity, all of which are indicative o f a decrease in population size, when present results are compared to data collected in the same area 22 years earlier. Results of the yield per recruit curve indicate that lemon sole are currently being over-fished o f f the west coast of Ireland. Problems of selectivity within the sampling method, particularly at the discarding stage, may have influenced the outcome of results of the models used in the assessment of this stock. Therefore, additional/future work on this species should include catch data which incorporates discards and not landings data alone.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
A comparison of innovations used in natural resource companies along the west coast of Ireland Delaney, Mary Theresa (Galway-Mayo Institute of Technology, 2010)The research aims to understand the capabilities and limitations of innovation models and processes in natural marine companies in allowing the production of socially desirable innovation and the spill-over or knowledge ...
The construction, survival, and use of signal defensible guard houses on the Irish coast / Rathbone, Stuart (2021)In the first decade of the 19th century a new system of 81 military signal stations were constructed around the Irish coast. At 74 signal stations, purpose-built signal defensible guard houses were constructed, and some ...
Age, growth, reproductive biology and population dynamics of the common megrim Lepidorhombus whiffiagottis (Walbaum, 1792) from off the west coast of Ireland Robson, Stephen M. (Galway-Mayo Institute of Technology, 2004)A total of 4,964 common megrim Lepidorhombus whiffiagonis, were examined from commercial catches in Divisions VII b^, off the west coast of Ireland, between April 1997 and February 2001. A sex ratio of 31.8:1 females to ...