Is the ballan wrasse (Labrus bergylta) two species? Genetic analysis reveals within-species divergence associated with plain and spotted morphotype frequencies
Abstract The ballan wrasse (Labrus bergylta) is a marine fish belonging to the family Labridae characterized by 2 main morphotypes that occur in sympatry: spotty and plain. Previous studies have revealed differences in their life‐history traits, such as growth and maturation; however, the genetic relationship between forms is presently unknown. Using 20 recently developed microsatellite markers, we conducted a genetic analysis of 41 and 48 spotty and plain ballan wrasse collected in Galicia (northwest Spain). The 2 morphotypes displayed highly significant genetic differences to each other (F ST = 0.018, P < 0.0001). A similar degree of genetic differentiation (F ST = 0.025, P < 0.0001) was …
Movement patterns of temperate wrasses (Labridae) within a small marine protected area
The movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km2 ) 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. The extent of movement was not related to body size or sex. These results imply that a network of small strategically located marine protected areas can be used as management tools to protect wrasses from size- and sex-selective fishing mortality.
Sex- and size-selective harvesting of corkwing wrasse (Symphodus melops)—a cleaner fish used in salmonid aquaculture
Fishery-induced changes in sex ratios can have negative effects on reproductive rates and affect sexual selection and evolutionary trajectories. Here, we investigate sex- and size-selectivity of the fishery for corkwing wrasse (Symphodus melops) in Western Norway. The males that build and guard nests (nesting males) grow faster than females and sneaker males. Corkwing wrasse were tagged (n = 1057) during (May–June) and after (July) the spawning period in 2014 within a no-take site and in a nearby site open for fishing. We monitored the fishery within and nearby the tagging sites from June to October and sampled recaptures on all commercial fishing trips. Fishing mortality was higher for nes…
Isolation and characterization of twenty microsatellite loci for the ballan wrasse, Labrus bergylta
Published version of an article in the journal: Conservation Genetics Resources. Also available from the publisher at: http://dx.doi.org/10.1007/s12686-013-0114-3 Open Access We developed 20 nuclear microsatellite DNA markers from tri- and tetra-nucleotide enriched libraries in the ballan wrasse. In our dataset (N = 241), the detected number of alleles per locus ranged from 2 to 12, and the observed and expected heterozygosity varied from 0.251 to 0.778 and from 0.286 to 0.804, respectively. Cross amplification with the goldsinny wrasse resulted in two usable loci whereas the corkwing wrasse amplified in one locus. The ballan wrasse is an important resource for aquaculture as it delouses fa…
Effects of UV Radiation and Diet on Polyunsaturated Fatty Acids in the Skin, Ocular Tissue and Dorsal Muscle of Atlantic Salmon (Salmo salar) Held in Outdoor Rearing Tanks
Article published in Photochemistry and Photobiology, 86 (4): 909-919 JUL-AUG 2010 The effect of UV radiation (UVR) on juvenile Atlantic salmon (Salmo salar) was assessed by measuring the fatty acid (FA) profiles of muscle, dorsal and ventral skin, and ocular tissues following 4-month long exposures to four different UVR treatments in outdoor rearing tanks. Fish were fed two different diets (Anchovy- and Herring-oil based) that differed in polyunsaturated fatty acid (PUFA) concentrations. Anchovy-fed salmon had higher concentrations of ALA (alpha-linoleic acid; 18:3n-3), EPA (eicosapentaenoic acid; 20:5n-3) and DPA (docosapentaenoic acid, 22:5n-3) in their muscle tissues than fish fed the H…
Mind the depth: The vertical dimension of a small-scale coastal fishery shapes selection on species, size, and sex in wrasses
Small‐scale fisheries (SSFs) tend to target shallow waters, but the depth distributions of coastal fish can vary depending on species, size, and sex. This creates a scope for a form of fishing selectivity that has received limited attention but can have considerable implications for monitoring and management of these fisheries. We conducted a case study on the Norwegian wrasse fishery, a developing SSF in which multiple species are caught in shallow waters (mean depth = 4.5 m) to be used as cleaner fish in aquaculture. Several of these wrasses have life histories and behaviors that are sensitive to selective fishing mortality, such as sexual size dimorphism, paternal care, and sex change. A…