Fisheries sustainability is recognized to have four pillars: ecological, economic, social (including cultural) and institutional (or governance). Although international agreements, and legislation in many jurisdictions, call for implementation of all four pillars of sustainability, the social, economic and institutional aspects (i.e., the “human dimensions”) have not been comprehensively and collectively addressed to date. This study describes a framework for comprehensive fisheries evaluation developed by the Canadian Fisheries Research Network (CFRN) that articulates the full spectrum of ecological, economic, social and institutional objectives required under international agreements, together with candidate performance indicators for sustainable fisheries. The CFRN framework is aimed at practical fisheries evaluation and management and has a relatively balanced distribution of elements across the four pillars of sustainability relative to 10 alternative management decision support tools and indicator scorecards, which are heavily focused on ecological and economic aspects. The CFRN framework has five immediate uses: (a) It can serve as a logic frame for defining management objectives; (b) it can be used to define alternate management options to achieve given objectives; (c) it can serve as a tool for comparing management scenarios/options in decision support frameworks; (d) it can be employed to create a report card for comprehensive fisheries management evaluation; and (e) it is a tool for practical implementation of an integrated social–ecological system approach.

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Early post-settlement events can have a large impact on the successful recruitment of benthic invertebrates. A field caging experiment was conducted in 2007 to examine whether predation by, and/or competition with, small macrofauna affects mortality or growth of recently settled sea urchins Strongylocentrotus droebachiensis or sea stars Asterias spp. Kelp was added to half of the sea urchin cages to test whether the addition of this food source (including its associated biofilms) altered growth or survival. Sea urchins survived 25% better in cages where the other organisms were removed, indicating that predation or bulldozing likely plays an important role. The growth of sea urchins was greatest in cages without other organisms and lowest in cages with other organisms and with food, possibly indicating competition that affects sea urchin behaviour. Sea stars showed the opposite trend in survival. A greater proportion of sea stars survived in cages where the other organisms were present (31.3 vs. 11.5%), presumably due to them being a food source for the sea stars, indicating that starvation, cannibalism and/or competition for food are likely important for recent settlers of this taxon. The declines in abundance in the cages were greater than those in the natural environment for sea urchins, but similar for sea stars, suggesting that caution is required when extrapolating experimental results to the field. These results indicate that multiple factors, which differ between these species, affect early post-settlement growth and mortality. KEY WORDS: Strongylocentrotus droebachiensis · Asterias spp. · Mortality · Growth · Predation · Competition · Early post-settlement · Natural declinesResale or republication not permitted without written consent of the publisher 90% mortality in juvenile limpets due to interspecific competition, an amount comparable to predation.However, competition does not have to be fatal, and may be more likely to have sublethal impacts on processes such as growth or fecundity (Birch 1957, Tomas et al. 2005. Intraspecific competition can reduce growth at high densities (e.g. Marsden 2002, Silina 2008 or reduce growth rates for small individuals forced to compete with larger ones (e.g. Kautsky 1982). Reduced growth rates can prolong the time it takes to reach recruitment (if defined by size) and sexual maturity.When predation and competition are examined together, the presence of predators often results in a greater reduction in abundance, fecundity and growth than does the presence of competitors (e.g. Aukema & Raffa 2002, Beal 2006. However, few studies have examined the effects of both predation and competition on juveniles. In the sea urchin Evechinus chloroticus, juveniles had higher densities when predators were excluded, regardless of the presence of adult conspecifics (Andrew & Choat 1982). Beal (2006) found that, while both predation and intraspecific competition had significant impacts on the survival of juvenile clams Mya arenaria, predation accounted for 45% of the variabi...

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