An Approach to Defining Stock Complexes for U.S. West Coast Groundfishes Using Vulnerabilities and Ecological Distributions

Abstract

The Magnuson–Stevens Fishery Conservation and Management Act (MSA) requires active management of all stocks at risk of overfishing or otherwise in need of conservation and management. In the Pacific Fishery Management Council groundfish fishery management plan, about two‐thirds of the more than 90 managed stocks are currently without traditional assessments to help define stock status in relation to management targets. Stock complexes are often employed for management purposes in such situations. The guidelines issued in response to the 2006 MSA amendments defined a complex as a group of stocks with similar geographic distributions, life histories, and vulnerabilities to fisheries. This work uses productivity–susceptibility analysis (PSA) to measure the vulnerabilities of 90 managed groundfish stocks, 64 of which are currently managed within stock complexes. These stock complexes are reevaluated by first using a partitioning cluster analysis to group the stocks by depth and latitude. Vulnerability reference points are then established based on the PSA results to determine vulnerability groups of low, medium, high, and major concern within each ecological group. This method is a simple and flexible approach to incorporating vulnerability measures into stock complex designations while providing information with which to prioritize stock‐ and complex‐specific management. Received September 28, 2010; accepted February 23, 2011

Stable‐isotope analysis of a deep‐sea benthic‐fish assemblage: evidence of an enriched benthic food web

“…The Pacific Fishery Management Council is currently discussing whether to include B. trachura , E. bathybius , C. acrolepis , A. pectoralis and A. tenebrosus , among others, in the west coast groundfish Fishery Management Plan (FMP) as they are caught in similar amounts to managed species. Vulnerability scores, determined by productivity–susceptibility analysis (PSA), were low with the exception of A. pectoralis , which was classified as having a medium vulnerability score (Cope et al , 2011; PFMC, 2011).…”

Assessing the risk of vulnerable species exposure to deepwater trawl fisheries: the case of orange roughyHoplostethus atlanticusto the west of Ireland and Britain

“…This method has been successfully applied in situations where the majority of stocks are data deficient such as in fisheries certifications by the Marine Stewardship Council 1 , for fisheries management under the Magnuson Stevens Fishery Conservation and Management Act in the US (Cope et al 2011;Ormseth and Spencer 2011) and for management of bycatch species in Australia (Zhou and Griffiths 2008;Zhou et al 2009). Here, as a first step, a PSA on the deepwater fish community is presented to analyse the relative vulnerability of orange roughy in relation to other species of the mixed deepwater trawl fishery operated to the west of Ireland and Britain.…”

Performance of Surplus Production Models with Time‐Varying Parameters for Assessing Multispecies Assemblages

“…Due to the lack of species-specific data collection and the logistical challenges of assessing numerous species, many regional fisheries management councils have moved toward assessing some groups of species as stock complexes (Carmichael and Fenske 2011). For this approach to be successful, the life history and fishery characteristics of the species in the complex must be homogeneous (Cope et al 2011). Defining appropriate stock complexes that, when assessed as a group, will not result in overexploitation of component stocks will be a serious challenge in regions with limited life history research and data collection programs (Carmichael and Fenske 2011).…”