Knowledge of aquaculture–environment interactions is essential for the development of a sustainable aquaculture industry and efficient marine spatial planning. The effects of fish and shellfish farming on sessile wild populations, particularly infauna, have been studied intensively. Mobile fauna, including crustaceans, fish, birds and marine mammals, also interact with aquaculture operations, but the interactions are more complex and these animals may be attracted to (attraction) or show an aversion to (repulsion) farm operations with various degrees of effects. This review outlines the main mechanisms and effects of attraction and repulsion of wild animals to/from marine finfish cage and bivalve aquaculture, with a focus on effects on fisheries‐related species. Effects considered in this review include those related to the provision of physical structure (farm infrastructure acting as fish aggregating devices (FADs) or artificial reefs (ARs), the provision of food (e.g. farmed animals, waste feed and faeces, fouling organisms associated with farm structures) and some farm activities (e.g. boating, cleaning). The reviews show that the distribution of mobile organisms associated with farming structures varies over various spatial (vertical and horizontal) and temporal scales (season, feeding time, day/night period). Attraction/repulsion mechanisms have a variety of direct and indirect effects on wild organisms at the level of individuals and populations and may have implication for the management of fisheries species and the ecosystem in the context of marine spatial planning. This review revealed considerable uncertainties regarding the long‐term and ecosystem‐wide consequences of these interactions. The use of modelling may help better understand consequences, but long‐term studies are necessary to better elucidate effects.

ABSTRACT:The relationship between the somatic growth rate (G) and feeding level (unfed, intermediate, and maximum rations) of age-0 juvenile cod Gadus morhua and haddock Melanogrammus aeglefinus was quantified at different temperatures. Laboratory trials were conducted using 2 sizeclasses of cod (3.6 to 5.6 cm standard length [SL], and 8.1 to 12.4 cm SL) at 5, 8, 12, and 15°C, and 1 size-class of haddock (6.0 to 9.6 cm SL) at 8 and 12°C. The shape of the growth-feeding relationship was well described by a 3-parameter asymptotic function for cod and by a linear function for haddock (R 2 range = 0.837 to 0.966). The growth rate and scope for growth were maximum at 12°C, whereas growth efficiency was greatest (26.0 to 32.2%) at temperatures between 5 and 8°C. Juvenile cod held at 15°C exhibited reduced rates and efficiencies of somatic growth compared to fish at other temperatures. Biochemical-based growth indicators for age-0 juveniles were calibrated from measurements of the amounts of RNA, DNA, and protein in white muscle samples. A multiple linear regression using RNA:DNA and temperature as independent variables explained a significant portion of the variability observed in G of juvenile cod (R 2 = 0.716) and haddock (R 2 = 0.637). This relationship may be useful in estimating recent growth of age-0 juvenile cod and haddock in the field.

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Histological changes of the digestive system and its associated glands, and structures of the jaw were studied in summer flounder Paralichthys dentatus from hatching (day 0) until day 44. Specimens for this study were hatched from artificially spawned broodstock and maintained in the laboratory (20 1 C). During the first 3 days after hatching, the formation of the oral jaw apparatus, lengthening of the digestive tube, yolk resorption, and mucosae differentiation are the most conspicuous elements of development. The larval digestive system is morphologically ready to process external food at the time of mouth opening (3-4 days after hatching). Epithelial cells of the anteromedian and the posterior intestine show evidence of lipid and protein absorption, respectively, after first feeding. The most noticeable events occurring during the next month of independent life are an increase in mucosal folding, cellular differentiation in the luminal epithelia, gut segmentation and looping, and liver growth. Gastric glands and pyloric caeca appear by day 31 and complete the morphological digestive features characteristic of the juvenile stage. 1995 The Fisheries Society of the British Isles

Abstract-The U.S. Environmental Protection Agency (EPA) is reevaluating the risks associated with 2,3,7,8-tetrachlorodibenzop-dioxin and related chlorinated hydrocarbons (CHCs). Most information currently available concerning CHC toxic action and biological effects focuses on the responses of individual organisms, as opposed to the potential impacts of CHCs on populations, communities, or ecosystems. In support of EPA's reevaluation, survivorship and reproduction data from two previous studies involving the estuarine fish, Fundulus heteroclitus (Linnaeus), exposed as adults to either dioxin or polychlorinated biphenyls (PCBs), were interpreted at the population level using a stage-classified model of F. heteroclitus population dynamics. The studies differed with respect to the route of exposure of the parental stock: dietary exposure to dioxin in the laboratory and natural exposure to PCBs at the New Bedford Harbor, Massachusetts marine Superfund site. The CHC effects documented in these studies were used to modify fertility and survivorship in the population model. The finite population multiplication (growth) rate, estimated using the model, was used as the measure of population-level effect. In both cases, a negative relationship was observed between CHC dose (quantified as dioxin whole-body burden and liver burden of non-ortho-and mono-ortho-substituted PCB congeners) and population growth rate. The dose-response relationships developed in this study provide useful information for assessing the ecological risks of CHCs to estuarine fish populations.