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Cormorants and other wildlife populations have come in real or perceived conflicts with humans over exploited fish stocks. From gut contents of cormorants, and using an extension of the Catch equation, we estimated the degree of short term competition between great cormorants and coastal fisheries in two areas along the Swedish Baltic Sea. Cormorants consumed 10 and 44%, in respective area, of the fish biomass of six fish species harvested by humans; eel, flounder, herring, perch, pike, and whitefish. On average, cormorants consumed smaller individuals than harvested in fisheries. But for perch, cod and flounder, cormorants consumed harvestable sized fish corresponding >20% of human catches. Our competition model estimated the direct decrease in fisheries catches due to cormorant predation to be <10% for all species except flounder (>30%) and perch (2–20%). When also including the indirect effects of cormorant predation on smaller fish that never reached harvestable size, the estimated decrease in fisheries catches at least doubled for perch (13–34%) and pike (8–19%). Despite large uncertainties, our model indicates that cormorants may locally have a direct impact on human catches of at least flounder, and when incorporating indirect effects also on perch and pike. The study indicates that the degree of competition between cormorants and humans varies substantially between areas. We also included economical values in the model and concluded that for the commercially most important species, eel and cod, the estimated economic impact of cormorants on fisheries was low.

BackgroundGood work ability is very important in young workers, but knowledge of work situations that influence work ability in this group is poor. The aim of this study was to assess whether changes in self-reported work factors are associated with self-reported work ability among young female and male workers.MethodsA sample of 1,311 (718 women and 593 men) was selected from a Swedish cohort of workers aged 21–25 years. At baseline and at 1-year follow-up, participants completed a self-administrated questionnaire including ratings of physical and psychosocial work factors and current work ability. Prevalence ratios were calculated to assess univariate and multivariate associations between changes in work factors and changes in work ability.ResultsDecreased job control (PR 1.7, 95% CI 1.49–2.12) and increased negative influence of job demands on private life (PR 1.5, 95% CI 1.25–1.69) were associated with reduced work ability for both female and male workers in the multivariate analyses. Among female workers, an association was found between improved work ability and increased social support at work (PR 2.4, CI 1.43–3.95). For male workers, increased job control (PR 2.3, 95% CI 1.21–4.54) and decreased negative influence of job demands on private life (PR 2.1, 95% CI 1.10–3.87) were associated with improved work ability in the multivariate analyses.ConclusionsDecreased job control and increased negative influence of job demands on private life over time seem to be the most important work factors associated with reduced work ability among young workers of both sexes. Increased social support at work, increased job control, and decreased negative influence of job demands on private life were also found to be the main work factors associated with improved work ability, although with possible gender differences.

Access to the published version may require journal subscription. Published with permission from: Springer Verlag.Standard set statement from the publisher:"The final publication is available at Springer via http://dx.doi.org/ 10.1007/s00436-014-4187-z" Epsilon Open Archive http://epsilon.slu.se or some other variable which correlates with salinity, limits the distribution in the northern part. Sealworm (Pseudoterranova decipiens) infection in grey seals (Halichoerus grypus), cod (Gadus 30Keywords: Baltic Sea, cod, grey seal, Pseudoterranova, sealworm, sculpin. 32 Introduction 33Infection by the larval stages of the parasitic sealworm, Pseudoterranova sp., in commercial fish 34 species has been of great concern in the North Atlantic fisheries (McClelland 2002). So far it has 35 not been raised as an urgent issue in the Baltic Sea area except in the southern parts (Myjak et 36 al., 1994, Szostakowska et al., 2005, Buchmann and Kania, 2012, Nadolna and Podolska, 2014. 37However, with an increasing population of seals, the parasite's final hosts, there are concerns of 38 an increasing problem. Data on the population of grey seals in the Baltic suggest an annual rate 39 of increase of 7.5% since 1990; (Harding et al. 2007) and in 2013 the counted population on 40 shore was 28,000 (www.rktl.fi). The highest density of grey seals in the Baltic is found between 41 latitudes 58° and 61°, which correspond with ICES subdivision 27 in the north to subdivision 31 42 in the south (Figure 1). There are also scattered colonies along the Swedish coast in the southern parasite, the increasing seal population is a problem. 47Pseudoterranova sp. are intestinal roundworms or nematodes belonging to the family Anisakidae 48 and can be considered a cosmopolitan genus, with a confusing taxonomy (Paggi et al. 2000). 49Genetic studies by Buchman and Kania (2012) determined that the nematodes found in cod flesh 50 from the southern Baltic are Pseudoterranova decipiens. The sealworm has a complex life cycle, 51 with a free-living stage and three obligate hosts required for the parasite to complete its life-52 cycle. The eggs are excreted in the faeces of a seal and sink to the sea floor where they hatch into 53 free-living larvae. A benthic invertebrate ingests the larvae. After the infected invertebrate is 54 eaten by a fish, the larvae migrate from the stomach of the fish into the muscle tissue. It is at this 80The spatial distribution in the Baltic Sea is of special interest because of its uniqueness in being a 81 brackish sea. Salinity has been shown to limit the survival of the sealworm larvae (Measures, lower range of salinity in the Baltic Sea, it is not known how well the sealworms survive. 89The aim of this study was to examine the relative presence and distribution of sealworms in the Materials and Methods 99Fish and parasite sampling 100 Fish were collected along the east coast of Sweden, using different types of gear, such as gill In order to support this consistency, the same light table was used throughout the st...

Boström, M. K., Östman, Ö., Bergenius, M. A. J., and Lunneryd, S-G. 2012. Cormorant diet in relation to temporal changes in fish communities. – ICES Journal of Marine Science, 69: 175–183. The stomach contents of 229 great cormorants (Phalacrocorax carbo sinensis) shot between March and October 2009 along the Swedish east coast were analysed for differences in diet between gender, age, and breeding phase. Sticklebacks (Gasterosteus aculeatus and Pungitius pungitius) were the most common prey, followed by eelpout (Zoarces viviparus), herring (Clupea harengus membras), and cyprinids (Cyprinidae). Diet did not differ between age and gender, but changed over the breeding season. The different phases explained around 10% of the total variation in stomach content between cormorants, suggesting no major shift in diet over the breeding season. The diet of cormorants in 2009 was compared with the results of a study conducted in the same area in 1992. There were evident changes in the diet between 1992 and 2009, with less perch (Perca fluviatilis) and cyprinids and more eelpout and herring in 2009. This change in diet could partly be related to changes in the fish community. The seasonal changes in diet composition of whole stomachs were less notable than in many previous studies, but long-term changes in the fish communities may induce changes in cormorant diet. It is clearly important to use stomach contents in areas with many small fish species for a comprehensive assessment of cormorant diet.