全球智库信息集成服务系统(G2TT): Long-term trend in the maturation reaction norm of two cod stocks.

G2TT

来源类型	Article
规范类型	其他
DOI	10.1890/03-5066
	Long-term trend in the maturation reaction norm of two cod stocks.
	Barot S; Heino M; O'Brien L; Dieckmann U
发表日期	2004
出处	Ecological Applications 14 (4): 1257-1271
出版年	2004
语种	英语
摘要	Average age and size at maturation have decreased in many commercially exploited fish stocks during the last decades. This phenomenon could be either a direct phenotypic response to some environmental variation or the evolutionary consequence of some selective pressure. Traditionally used maturation indices, e.g., the age and size at which 50% of individuals are mature, are not appropriate to assess the causes of changes in maturation because they are influenced, in addition to maturation per se, by growth and survival. To make up for this shortcoming, we use a reaction-norm-based approach to disentangle evolutionary changes and phenotypic plasticity. A method is presented to estimate the reaction norm for age and size at maturation from data commonly gathered for the management of fisheries. This method is applied to data on Georges Bank and Gulf of Maine stocks of Atlantic cod (Gadus morhua). The results show that maturation reaction norms in these stocks have shifted significantly downward, resulting in a tendency to mature earlier at smaller size. These findings support the hypothesis that an evolutionary trend, probably caused by high fishing mortalities, is partially responsible for the observed decrease in age and size at maturation in these cod stocks. Two independent reasons justify this interpretation. First, there is no corresponding trend in growth that would suggest that improved feeding conditions could have facilitated maturation. Second, the results are based on maturation reaction norms, from which the known confounding effects of the growth and mortality variation are removed. Consequences of fisheries-induced evolution for the sustainability of the fishery are discussed.
主题	Adaptive Dynamics Network (ADN)
关键词	Cod Fisheries Fish stocks Management strategies Gadus morhua Georges Bank cod stock Gulf of Maine cod stock Life-history evolution Logistic regression Maturation reaction norm Maturity ogive Phenotypic plasticity Sustainability of cod fisheries
URL	http://pure.iiasa.ac.at/id/eprint/7163/
来源智库	International Institute for Applied Systems Analysis (Austria)
引用统计
资源类型	智库出版物
条目标识符	http://119.78.100.153/handle/2XGU8XDN/128386
推荐引用方式 GB/T 7714	Barot S,Heino M,O'Brien L,et al. Long-term trend in the maturation reaction norm of two cod stocks.. 2004.