In many developed countries fish and shellfish are increasingly promoted as healthy alternatives to other animal protein. We analysed how much fish was available to UK and global populations after accounting for processing losses, and compared this to recommended levels of fish consumption. In 2012, UK domestic fish landings per capita fell 81% below the recommended intake, although declines were masked by increased imports and aquaculture from the 1970s onwards. Global wild fish supply per capita declined by 32% from its peak in 1970. However, overall fish supplies per capita increased by 10% over the same period due to rapidly expanding aquaculture production. Whilst aquaculture has so far prevented a downturn in global fish supplies, many developed nations continue to aspire to consume more fish than they produce. Until demand is balanced with sustainable methods of production governments should consider carefully the social and environmental implications of greater fish consumption.

Interactions between open-net pen finfish aquaculture and lobster catches in a sheltered bay in Nova Scotia, Canada, were investigated using fishermen’s participatory research in annual lobster trap surveys over seven years.Fishermen recorded lobster catches during the last two weeks of May from 2007 to 2013. Catches for each trap haul were recorded separately for ovigerous and market-sized lobsters. Catch trends within the bay were compared to regional trends. Results of correlation analyses indicated that ovigerous catch trends were strongly affected by the fish farm’s feeding/fallow periods. There was no significant correlation between trends for bay and LFA lobster landings.Patterns of lobster catch per unit effort extending over considerable distance in Port Mouton Bay appear to be influenced by proximity to the fish farm regardless of year-to-year variation in water temperatures and weather conditions. Odours and habitat changes surrounding open-net pen finfish operations are potential factors affecting lobster displacement.

Organochlorine contaminants in upper trophic-level consumers inhabiting Puget Sound are consistently higher than in those species inhabiting other west coast locations. We analyzed persistent organic pollutants (POPs) in the six most common fish prey of rhinoceros auklets breeding on Protection Island (Puget Sound), Tatoosh Island (WA coast), and Destruction Island (WA coast). Wet-weight concentrations of POPs ranged widely (PCBs: 1.6–25.0ng/g; DDTs: 0.2–56.0ng/g; PBDEs:<LOQ-49.0ng/g), but overall patterns showed fish from Puget Sound were 2–4 times more contaminated and had similar contaminant profiles compared to fish from the outer coast. Unexpectedly elevated PCB and PBDE concentrations in Chinook salmon from the outer coast likely reflected Columbia River. Calculating contaminant loads for auklet nestlings magnified differences observed between inland and outer coast fish prey. Monitoring of breeding auklets, their prey and other resident marine birds is needed to assess biomagnification impacts in the Puget Sound marine ecosystem.

Marine debris remains a global challenge, with significant impacts on wildlife. Despite this, there is a paucity of research examining public understanding about marine wildlife entanglement [MWE], particularly within an Australian context. The present study surveyed two hundred and thirteen participants across three coastal sites to assess familiarity with MWE and the effectiveness of a new community education initiative ‘Seal the Loop’ [STL]. Results revealed attitudes toward marine wildlife were very positive (M 40.5, SD 4.12); however 32% of participants were unable to correctly explain what MWE is and risks to wildlife were under-estimated. STL may be one method to enhance public understanding and engagement-if community familiarity with the program can be increased. For those aware of STL (<13% of the sample at the time of the study), findings revealed this was having a positive impact (e.g. learning something new, changed waste disposal behaviours).

The current study aimed to examine the relationship between metals in sediments and metal bioaccumulation in oyster tissue in a highly-modified estuary (Sydney estuary, Australia). While extensive metal contamination was observed in surficial sediments, suspended particulate matter and oyster tissue, a significant relationship between these media could not be established. No relationship was determined between sediment quality guidelines and oyster size or weight, nor with human consumption levels for metals in oyster tissue. Moreover, oyster tissue metal concentrations varied greatly at a single locality over temporal scales of years. Oyster tissue at all 19 study sites exceeded consumptions levels for Cu. Bioaccumulation of metals in oyster tissue is a useful dynamic indicator of anthropogenic influence within estuaries, however oysters cannot be used in Sydney estuary as a valid biomonitor due to overriding internal regulation (homoestasis) by the animal, or by external natural (sediment resuspension) and anthropogenic (sewer/stormwater discharges) pressures, or both.

Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712±780gDWm−2 and 1511±555gDWm−2, respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31±4.45, 402.82±130.25, and 28.12±2.08, respectively. The δ15N values (11.09±0.91‰ for C. linum; 9.27±2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms.

Ballast water exchange (BWE) is the most efficient measure to control the invasion of exotic species from ships. This procedure is being used for merchant ships in national and international voyages. The ballast water (BW) salinity is the main parameter to evaluate the efficacy of the mid-ocean ballast water exchange. The vessels must report to the Port State Control (PSC), via ballast water report (BWR), where and how the mid-ocean BWE was performed. This measure allows the PSC to analyze this information before the ship arrives at the port, and to decide whether or not it should berth.Ship BW reporting forms were collected from the Captaincy of Santana and some ships were visited near the Port of Santana, located in Macapá (Amazon River), to evaluate the BW quality onboard. We evaluated data submitted in these BWR forms and concluded that the BWE efficacy might be compromised, because data contained in these BWR indicate that some ships did not change their BW. We found mistakes in filling the BWR forms and lack of information. Moreover, these ships had discharged BW with high level of salinity, Escherichia coli and total coliforms into the Amazon River. We concluded that the authorities of the Amazon Region need to develop more efficient proceedings to evaluate the ballast water reporting forms and BW quality, as there is potential risk of future invasion of exotic species in Brazilian ports.

With increasing recognition that maximum oxygen demand is the unifying limit in tolerance, the first line of thermal sensitivity is, as a corollary, due to capacity limitations at a high level of organisational complexity before individual, molecular or membrane functions become disturbed. In this study the tropical mussel Perna viridis were subjected to temperature change of 0.4°C per hour from ambient to 8–36°C. By comparing thermal mortality against biochemical indices (hsp70, gluthathione), physiological indices (glycogen, FRAP, NRRT) and behavioural indices (clearance rate), a hierarchy of thermal tolerance was therein elucidated, ranging from systemic to cellular to molecular levels. Generally, while biochemical indices indicated a stress signal much earlier than the more integrated behavioural indices, failure of the latter (indicating a tolerance limit and transition to pejus state) occurred much earlier than the other indices tending towards thermal extremities at both ends of the thermal spectrum.

Superficial sediments from Lenga estuary in the VIII region of central Chile were analysed for Polychlorinated Biphenyls (PCBs) and Hexachlorobenzene (HCB). Organic carbon (OC) analysis was also performed and the statistical correlations (Pearson correlations) between compounds were also tested. Results showed the total PCB concentrations (ngg−1d.w.) fluctuated from ∼20 to 10,000. These levels are higher than those reported in other coastal sediments of the world. The PCB profile was dominated by middle to highly chlorinated congeners (6-Cl=40% and 7-Cl=30%). HCB concentrations (ngg−1d.w.), were lower than the PCBs and, fluctuated between 1 (at L1) and 870 (at L4). OC values ranged from 1% (L1) to 7% (L4) showing a significant positive correlations between OC% and PCBs (r=0.86; p<0.05) and for HCB (r=0.71). These results are an important contribution to knowledge of levels of POPs levels in coastal Chilean environments.

Twelve marine fish species collected from a thick-billed murre (Uria lomvia) breeding colony in northern Hudson Bay in the Canadian Arctic during 2007–2009 were analyzed for legacy organochlorines (e.g. PCBs, DDT), polybrominated diphenyl ethers (PBDEs), perfluorinated carboxylates (PFCAs) and sulfonates (PFSAs), and total mercury (Hg). No one species of prey fish had the highest levels across all contaminant groups analyzed. For the two pelagic fish species sampled, concentrations of the major organochlorine groups (e.g. Σ21PCB, ΣDDT, ΣCHL, ΣCBz), ΣPBDE, ΣPFCA and Hg were consistently higher in Arctic cod (Boreogadus saida) than in capelin (Mallotus villosus). Biomagnification factors from whole fish to thick-billed murre liver across all species were generally higher for Σ21PCB and ΣDDT. ΣPBDE did not biomagnify.