Institute of Community Medicine, Faculty of Health Sciences, University of Tromsoe, Tromsoe, Norway; Department of Occupational and Environmental Medicine, University Hospital North Norway, Tromsoe, Norway. Olga.Shiryaeva@uit.no
Trawler fishermen and merchant seafarers have tough working conditions. While workers in both occupations are exposed to a challenging environment, trawler fishermen are also engaged in onboard fish processing, which is considered to be additional exposure. The aim of the present study was to characterize respiratory health status in both groups of seamen.
In total 127 trawler fishermen and 118 merchant seafarers were enrolled during their regular medical health examinations. The study protocol comprised a standardized questionnaire, lung function test and measurements of fractional nitric oxide concentrations (FE(NO) ) in exhaled air.
Doctor-diagnosed asthma was reported only by trawler fishermen (3.9%, P?
On the basis of some epidemiological criteria, the work gives grounds for distinguishing the category of "new settlers" among the whole number of "newcomers". The time necessary for the social adaptation of new settlers is estimated, which makes it possible to take them into account together with permanent residents. The scheme of the division of the population according to the duration of their residence in the endemic area is proposed.
Pacific Halibut (Hippoglossus stenolepis) support culturally and economically important fisheries in the Gulf of Alaska, though recent decreases in mean size-at-age have substantially reduced fishery yields, generating concerns among stakeholders and resource managers. Among the prevailing hypotheses for reduced size-at-age is intensified competition with Arrowtooth Flounder (Atheresthes stomias), a groundfish predator that exhibited nearly five-fold increases in biomass between the 1960s and mid-2010s. To assess the potential for competition between Pacific Halibut and Arrowtooth Flounder, we evaluated their degree of spatiotemporal and dietary overlap in the Gulf of Alaska using bottom trawl survey and food habits data provided by the Alaska Fisheries Science Center (NOAA; 1990 to 2017). We restricted analyses to fish measuring 30 to 69 cm fork length and used a delta modeling approach to quantify species-specific presence-absence and catch-per-unit-effort as a function of survey year, tow location, depth, and bottom temperature. We then calculated an index of spatial overlap across a uniform grid by multiplying standardized predictions of species' abundance. Dietary overlap was calculated across the same uniform grid using Schoener's similarity index. Finally, we assessed the relationship between spatial and dietary overlap as a measure of resource partitioning. We found increases in spatial overlap, moving from east to west in the Gulf of Alaska (eastern: 0.13 ± 0.20; central: 0.21 ± 0.11; western: 0.31 ± 0.13 SD). Dietary overlap was low throughout the study area (0.13 ± 0.20 SD). There was no correlation between spatial and dietary overlap, suggesting an absence of resource partitioning along the niche dimensions examined. This finding provides little indication that competition with Arrowtooth Flounder was responsible for changes in Pacific Halibut alHHsize-at-age in the Gulf of Alaska; however, it does not rule out competitive interactions that may have affected resource use prior to standardized data collection or at different spatiotemporal scales.
In the 1980s and 1990s, the Government of Canada closed and/or issued advisories for a number of shellfish fisheries in coastal areas of British Columbia because of dioxin contamination. Only the direct health risks (i.e., cancer) of consuming contaminated shellfish for the general population were considered by the Government in the formulation of risk management options. A focus on the direct risks does not provide an adequate basis for risk decisions as the countervailing risks which may be created from management measures may easily be overlooked. This study describes the potential health impacts of risk management options for aboriginal coastal peoples in the management of dioxin contamination. Gold River and Powell River in British Columbia, Canada, are the areas of focus. The cancer risks of consuming dioxin contaminated shellfish for these sites are estimated. To assess the countervailing risks of management decisions for comparison, a scenario was developed in which First Nations peoples substitute shellfish with store-bought foods in their diets in the event of a fishery closure or advisory. Increases in mortality due to coronary heart disease are estimated. The results suggest that the health risks of dietary changes among aboriginal peoples may be as significant as those related to eating dioxin contaminated shellfish.
Bottom trawlers land around 19 million tons of fish and invertebrates annually, almost one-quarter of wild marine landings. The extent of bottom trawling footprint (seabed area trawled at least once in a specified region and time period) is often contested but poorly described. We quantify footprints using high-resolution satellite vessel monitoring system (VMS) and logbook data on 24 continental shelves and slopes to 1,000-m depth over at least 2 years. Trawling footprint varied markedly among regions: from 50% in some European seas. Overall, 14% of the 7.8 million-km2 study area was trawled, and 86% was not trawled. Trawling activity was aggregated; the most intensively trawled areas accounting for 90% of activity comprised 77% of footprint on average. Regional swept area ratio (SAR; ratio of total swept area trawled annually to total area of region, a metric of trawling intensity) and footprint area were related, providing an approach to estimate regional trawling footprints when high-resolution spatial data are unavailable. If SAR was =0.1, as in 8 of 24 regions, there was >95% probability that >90% of seabed was not trawled. If SAR was 7.9, equal to the highest SAR recorded, there was >95% probability that >70% of seabed was trawled. Footprints were smaller and SAR was =0.25 in regions where fishing rates consistently met international sustainability benchmarks for fish stocks, implying collateral environmental benefits from sustainable fishing.
A 25% lower cancer mortality was found for 1360 Swedish fishermen who fished on the Baltic Sea than for the general population. The fishermen consumed twice as much fish as the population in the same county. In spite of the low overall cancer mortality, increased mortality from myeloma, as well as increased incidences of gastric carcinoma and squamous cell cancer of the skin and lips, was observed in the cohort. The decrease in risk for ischemic heart disease was not significant. Whether the dietary intake of fatty acids and selenium from fish contributed to the decreased risk was difficult to evaluate. Moreover, whether the consumption of fish from the Baltic Sea, contaminated with, for example, polychlorinated dioxins and dibenzofurans and other persistent organochlorine substances, contributed to the observed increased specific cancer risks is not known. However, the net health effect of high fish consumption from the Baltic Sea seems to be positive.
One common method for estimating total catch is to multiply an estimate for CPUE, the catch per unit effort, by an estimate of total effort obtained from an independent second survey. In general, estimating total effort requires that sample times are chosen at random over the full fishing period; however, in practice, this may not always be possible and the usual estimator may be severely biased. Such a restriction in randomization is likely when aircraft are used to make instantaneous counts of fishing activity. This article proposes alternate estimators for use with both access and roving designs in conjunction with effort surveys for which sample times are not random. Ratio type estimators based on activity counts are developed under various scenarios and their performance examined under simulation. In addition, optimizing strategies for use with multiple activity counts are explored. Finally, data from an in-river gill net fishery on the Fraser River is used to illustrate these results.
Many hope that ocean waves will be a source for clean, safe, reliable and affordable energy, yet wave energy conversion facilities may affect marine ecosystems through a variety of mechanisms, including competition with other human uses. We developed a decision-support tool to assist siting wave energy facilities, which allows the user to balance the need for profitability of the facilities with the need to minimize conflicts with other ocean uses. Our wave energy model quantifies harvestable wave energy and evaluates the net present value (NPV) of a wave energy facility based on a capital investment analysis. The model has a flexible framework and can be easily applied to wave energy projects at local, regional, and global scales. We applied the model and compatibility analysis on the west coast of Vancouver Island, British Columbia, Canada to provide information for ongoing marine spatial planning, including potential wave energy projects. In particular, we conducted a spatial overlap analysis with a variety of existing uses and ecological characteristics, and a quantitative compatibility analysis with commercial fisheries data. We found that wave power and harvestable wave energy gradually increase offshore as wave conditions intensify. However, areas with high economic potential for wave energy facilities were closer to cable landing points because of the cost of bringing energy ashore and thus in nearshore areas that support a number of different human uses. We show that the maximum combined economic benefit from wave energy and other uses is likely to be realized if wave energy facilities are sited in areas that maximize wave energy NPV and minimize conflict with existing ocean uses. Our tools will help decision-makers explore alternative locations for wave energy facilities by mapping expected wave energy NPV and helping to identify sites that provide maximal returns yet avoid spatial competition with existing ocean uses.
Cites: Mar Environ Res. 2010 Jun;69(5):374-8120138659
Cites: Mar Environ Res. 2009 Oct;68(4):151-719560811
Cites: Proc Natl Acad Sci U S A. 2012 Mar 20;109(12):4696-70122392996
Commercial fishing is an extremely dangerous economic activity. In order to more accurately describe the risks involved, a specific injury coding based on the working process was developed.
Observation on six different types of vessels was conducted and allowed a description and a classification of the principal working processes on all kinds of vessels and a detailed classification for industrial trawlers. In industrial trawling, fish are landed for processing purposes, for example, for the production of fish oil and fish meal. The classification was subsequently used to code the injuries reported to the Danish Maritime Authority over a 5-year period.
On industrial trawlers, 374 of 394 (95%) injuries were captured by the classification. Setting out and hauling in the gear and nets were the processes with the most injuries and accounted for 58.9% of all injuries. A relatively large number of injuries occurred when embarking and disembarking. Specific risks were identified in a number of other working processes.
Specific areas for risk prevention in fishery may be identified by using a detailed classification system that takes both the specific method of fishing and the working processes into consideration.
Commercial fishing is one of the most dangerous occupations in the United States. During 1992-2008, an annual average of 58 reported deaths occurred (128 deaths per 100,000 workers), compared with an average of 5,894 deaths (four per 100,000 workers) among all U.S. workers. During the 1990s, safety interventions addressing specific hazards identified in Alaska resulted in a significant decline in the state's commercial fishing fatality rate. During 2007-2010, CDC expanded surveillance of commercial fishing fatalities to the rest of the country's fishing areas. To review the hazards and risk factors for occupational mortality in the U.S. commercial fishing industry, and to explore how hazards and risk factors differ among fisheries and locations, CDC collected and analyzed data on each fatality reported during 2000-2009. This report summarizes the results, which showed that, among the 504 U.S. commercial fishing deaths, the majority occurred after a vessel disaster (261 deaths, 52%) or a fall overboard (155 deaths, 31%). By region, 133 (26%) deaths occurred off the coast of Alaska, 124 (25%) in the Northeast, 116 (23%) in the Gulf of Mexico, 83 (16%) off the West Coast, and 41 (8%) in the Mid- and South Atlantic. Type of fishing was known in 478 deaths; shellfish (226, 47%) was the most common, followed by groundfish (144, 30%) and pelagic fish (97, 20%). To reduce fatalities in this industry, additional prevention measures tailored to specific high-risk fisheries and focusing on prevention of vessel disasters and falls overboard are needed.