Ballan wrasse Labrus bergylta is the largest species of wrasse inhabiting European waters and one of the longest-living species within the family Labridae. A large specimen was caught off the coast of Skjerjehamn, western Norway (total length = 410 mm; weight = 1274 g). The age of the specimen was determined to be 34 years old based on the analysis of its opercula bones.
View Article and Find Full Text PDFLumpfish (Cyclopterus lumpus) is a transatlantic marine fish displaying large population sizes and a high potential for dispersal and gene-flow. These features are expected to result in weak population structure. Here, we investigated population genetic structure of lumpfish throughout its natural distribution in the North Atlantic using two approaches: I) 4,393 genome wide SNPs and 95 individuals from 10 locations, and II) 139 discriminatory SNPs and 1,669 individuals from 40 locations.
View Article and Find Full Text PDFHunting and fishing are often size-selective, which favours slow body growth. In addition, fast growth rate has been shown to be positively correlated with behavioural traits that increase encounter rates and catchability in passive fishing gears such as baited traps. This harvest-induced selection should be effectively eliminated in no-take marine-protected areas (MPAs) unless strong density dependence results in reduced growth rates.
View Article and Find Full Text PDFThe movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km ) on the west coast of Norway were analysed over a period of 21 months. The mean distance between capture and recapture locations varied between 10 and 187 m, and was species and season specific.
View Article and Find Full Text PDFMarine protected areas (MPAs) are increasingly implemented worldwide to maintain and restore depleted populations. However, despite our knowledge on the myriad of positive responses to protection, there are few empirical studies on the ability to conserve species' mating patterns and secondary sexual traits. In male European lobsters (), the size of claws relative to body size correlates positively with male mating success and is presumably under sexual selection.
View Article and Find Full Text PDFRemoving individuals from a wild population can affect the availability of prospective mates and the outcome of competitive interactions, with subsequent effects on mating patterns and sexual selection. Consequently, the rate of harvest-induced evolution is predicted to be strongly dependent on the strength and dynamics of sexual selection, yet there is limited empirical knowledge on the interplay between selective harvesting and the mating systems of exploited species. In this study, we used genetic parentage assignment to compare mating patterns of the highly valued and overexploited European lobster () in a designated lobster reserve and nearby fished area in southern Norway.
View Article and Find Full Text PDFThe genetic impact of farmed fish escaping aquaculture is a highly debated issue. However, non-target species, such as cleaner fish used to remove sea lice from farmed fish, are rarely considered. Here, we report that wild corkwing wrasse (), which are transported long distances to be used as cleaner fish in salmon farms, escape and hybridize with local populations.
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