Ecotype variation in species exhibiting different life history strategies may reflect heritable adaptations to optimize reproductive success, and potential for speciation. Traditionally, ecotypes have, however, been defined by morphometrics and life history characteristics, which may be confounded with individual plasticity. Here, we use the widely distributed and polytypic freshwater fish spec...

We explored potential negative effects of exotic brown trout (Salmo trutta) on native sculpin (Cottus sp.) on the Logan River, Utah, USA by (i) examining factors most strongly correlated with sculpin abundance (e.g., abiotic conditions or piscivory?), (ii) contrasting the extent of brown trout predation on sculpin with that by native cutthroat trout (Oncorhynchus clarkii utah) and (iii) estimat...

Headwater species and peripheral populations that occupy habitat at the edge of a species range may hold an increased conservation value to managers due to their potential to maximize intraspecies diversity and species' adaptive capabilities in the context of rapid environmental change. The southern Appalachian Mountains are the southern extent of the geographic range of native Salvelinus fonti...

In this study, the use of chitosan prepared in different solvents (acetic acid, lactic acid) as a coating material was researched. The lowest mean pH, TBARS and TVB-N values among the treatment groups were observed in the acetic acid group. Similarly, the lowest growth of aerobic, lactic acid and Pseudomonas bacteria was recorded in this group. The growth of aerobic bacteria in the fillets that...

The diel partitioning of juvenile brown trout Salmo trutta foraging behaviour is controlled by a number of factors including predation risk, competition, temperature and food availability. The present study uses PIT-tagging and visual observation to asses the use of shelter and foraging behaviour of Danish wild juvenile brown trout (13.5–15.6 cm). The experiment was conducted in a fluvarium and...

For semi-anadromous brown trout, the decision whether or not to smoltify and migrate to the sea is believed to be made at the end of the preceding summer in response to both local environmental conditions and individual physiological status. Stressors experienced during the fall may therefore influence their propensity to migrate as well as carry over into the winter resulting in mortality when...

A strategy for species to survive climate change will be to change adaptively their way of life. Understanding rapid adaptation to climate change is therefore a priority for current research. In this issue, Turrero et al. (2012) use an original approach to unravel life history trait responses to climate change in two fish species (Salmo trutta and S. salar). Going against the flow, the authors ...

Phylogeographic, nested clade, and mismatch analyses of mitochondrial DNA (mtDNA) variation were used to infer the temporal dynamics of distributional and demographic history of brown trout (Salmo trutta). Both new and previously published data were analyzed for 1,794 trout from 174 populations. This combined analysis improved our knowledge of the complex evolutionary history of brown trout thr...

Brown trout (Salmo trutta) broodstock from a single population were separated prior to spawning and exposed to two different holding environments: a ‘raceway system’ and a ‘tank system’. Eggs were stripped from females and 13 measures of egg quality were collected, analysed individually, combined by principle components analysis into an integrated egg quality score which was validated against e...

the main objective of this study was to assess genetic comparison of two migratory forms of caspian trout salmo trutta caspius namely fall-run and spring-run. owing to the lack of information on its genetic differences, 5 microsatellite loci were used for 58 sample analyses. genomic dna was extracted from caudal fin using roche dna extraction kit and each pcr reaction was performed in a 25 ?l r...