Does spawning stock affect recruitment of New England groundfish?

We evaluated the effects of spawning-stock size on the recruitment abundanc e of 11 groundfish stocks in waters off New England. Empirical patterns of association between spawning biomass and recruitment were investigated usin g nonparametric approaches. For most stocks, higher recruitment occurred at high stock sizes and lower recruitment at low stock sizes. Survival ratios , indexed by recruitment per unit of spawning biomass, were higher at low s tock sizes and lower at high stock sizes-as expected under density dependen ce. To assess assumptions about recruitment dynamics, we analyzed constant- recruitment and compensatory and overcompensatory stock-recruitment models with uncorrelated and autocorrelated error structures, using Bayesian metho ds of statistical inference. Although no single model was adequate for all stocks, most groundfish had better than even odds of having density-depende nt dynamics, and most had better than even odds of having dynamics with unc orrelated environmental variation. While some geographic and taxonomic diff erences in potential productivity were apparent, all stocks exhibited compe nsation in survival ratio at low stock sizes, albeit with substantial varia tion. These results indicate that conservation measures intended to increas e the spawning biomass of New England groundfish will, on average, result i n higher recruitment and, eventually, in increased and more stable fishery yields.