Many coral reefs worldwide have undergone phase shifts to alternate, degraded assemblages because of the combined effects of over-fishing, declining water quality, and the direct and indirect impacts of climate change. Here, we experimentally manipulated the density of large herbivorous fishes to test their influence on the resilience of coral assemblages in the aftermath of regional-scale bleaching in 1998, the largest coral mortality event recorded to date. The experiment was undertaken on the Great Barrier Reef, within a no-fishing reserve where coral abundances and diversity had been sharply reduced by bleaching. In control areas, where fishes were abundant, algal abundance remained low, whereas coral cover almost doubled (to 20%) over a 3 year period, primarily because of recruitment of species that had been locally extirpated by bleaching. In contrast, exclusion of large herbivorous fishes caused a dramatic explosion of macroalgae, which suppressed the fecundity, recruitment, and survival of corals. Consequently, management of fish stocks is a key component in preventing phase shifts and managing reef resilience. Importantly, local stewardship of fishing effort is a tractable goal for conservation of reefs, and this local action can also provide some insurance against larger-scale disturbances such as mass bleaching, which are impractical to manage directly.

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Artículo de publicación ISISome 290 species of squids comprise the order Teuthida that belongs to the molluscan Class Cephalopoda. Of these, about 30-40 squid species have substantial commercial importance around the world. Squid fisheries make a rather small contribution to world landings from capture fisheries relative to that of fish, but the proportion has increased steadily over the last decade, with some signs of recent leveling off. The present overview describes all substantial squid fisheries around the globe. The main ecological and biological features of exploited stocks, and key aspects of fisheries management are presented for each commercial species of squid worldwide. The history and fishing methods used in squid fisheries are also described. Special attention has been paid to interactions between squid fisheries and marine ecosystems including the effects of fishing gear, the role of squid in ecosystem change induced by overfishing on groundfish, and ecosystem-based fishery management

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Dumpling squid, Euprymna tasmanica, show consistent individual differences in behaviour that can be classified according to indices reflecting shy–bold, activity and reactivity responses. Using crosses of wild‐caught single males to multiple females with known behavioural phenotypes, this study estimated patterns of additive genetic and residual variance in these behavioural traits from offspring of squid in two contexts, a threat (antipredator) and feeding (foraging) test. Genetic contributions to behavioural expression were dependent on test context. Behaviours in antipredator contexts had significant heritabilities (h2 = 0.2–0.8) while behaviours from foraging contexts had lesser additive genetic and greater residual components (h2 = 0.05–0.08). Personality trait variation in females was not related to her fecundity. Female boldness in foraging situations, which co‐varied with body size, explained small but significant variation (∼21%) in brood hatching success, while successful fertilization was determined by positive assortion of mate pairs according to their shy–bold phenotype. These results are discussed in terms of the ecological and evolutionary significance of animal ‘personality’ traits in wild populations of animals.