Density-dependant Growth in the Northwest Atlantic Stock of Atlantic Mackerel (Scomber scombrus)

摘要

Density-dependent growth relationships in the Northwest Atlantic stock of Atlantic mackerel (Scomber scombrus) were investigated with regression and non-parametric statistical procedures. Mean weight at ages 1-3 for research survey caught and ages 2-4 for commercially caught fish were found to be significantly and negatively correlated with stock density. Weight-at-age of fish from the 1978-82, and 1984 cohorts were significantly different at ages l, 2 and 3. The 1982 cohort was found to be one of the slowest growing on record; it is also one of the largest recruiting year-classes that has been observed. Results suggested that a two stage growth model that accounts for different distribution of juvenile and adult fish may be appropriate for this stock. Early growth may be related to year-class size, whereas stock size may be more influential after juvenile fish join the adult stock further offshore