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Ecosystem models are one way of implementing an integrated approach to the recovery of heavily depleted systems like those on and over seamounts. We review the three main types of ecosystem models that have been applied in understanding seamounts, their ecology and fisheries; we describe Ecopath-with-Ecosim food web simulation models, agent-based models, and a more complex biogeochemical spatially explicit model (Atlantis). We discuss their capabilities, limitations, uncertainty, advantages and disadvantages, and present some examples. Ecosystem models of seamounts enable us to evaluate true fisheries sustainability in an ecosystem context and analyse alternative management scenarios for seamount ecosystems.

Nutritional composition of a composite sample of whole green crabs, Carcinus maenas (L.), was undertaken to evaluate efficacy as a forage fish replacement for seafood-meal manufacture. Whole green crabs sampled from New Hampshire waters were ground together and analyzed for proximate profile (moisture, lipid, protein, fiber, and ash), fatty acid profile, amino acid profile, mineral composition, and mercury content. Green crab mince contained 16.55 ± 0.29% ash, 12.27 ± 0.25% protein, and 0.21 ± 0.07% lipid, and comprised all amino acids essential for chickens and most species of fish. Fatty acid composition of ground green crab was 67.98% unsaturated, and 23.29% saturated, and was richer in eicosapentaenoic acid (EPA) than docosahexaenoic acid (DHA). Levels of mercury in green crab mince were below testable limits. The nutritional profile of green crab mince was evaluated relative to the nutritional profile of menhaden from the literature, and possible agrifeed applications for whole green crab were considered. Green crab showed great potential as a forage fish replacer in seafood-meal applications for chickens and ash tolerant species of fish.

1. Fishing is a strong selective force and is supposed to select for earlier maturation at smaller body size. However, the extent to which fishing-induced evolution is shaping ecosystems remains debated. This is in part because it is challenging to disentangle fishing from other selective forces (e.g. size-structured predation and cannibalism) in complex ecosystems undergoing rapid change.