| 1. |
- Turesson, Håkan, et al.
(author)
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Foraging behaviour and capture success in perch, pikeperch and pike and the effects of prey density
- 2004
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 65:2, s. 363-375
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Journal article (peer-reviewed)abstract
- The effect of school size on capture success in three different piscivores, perch Perca fluviatilis, pikeperch Stizostedion lucioperca and pike Esox lucius, was investigated. Roach Rutilus rutilus were used as prey in a pool experiment where individual predators were presented prey at densities of one, two, four, eight and 16 prey, respectively. Treatments were replicated seven times for each predator species. Perch was at first virtually unable to capture a prey from a school and suffered a significant confusion effect with increasing prey density. The effect, however, was limited in the long run, as the perch was a very effective predator in its hunting strategy where it singled out and repeatedly attacked single prey irrespective of prey density or school size. Pikeperch and pike were able to attack and capture prey at any prey density equally successfully and thus did not suffer from a confusion effect. Neither did these predators receive any apparent advantages from increasing prey density. (C) 2004 The Fisheries Society of the British Isles.
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| 2. |
- Ah-King, M., et al.
(author)
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Why is there no sperm competition in a pipefish with externally brooding males? Insights from sperm activation and morphology
- 2006
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 68:3, s. 958-962
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Journal article (peer-reviewed)abstract
- Nerophis ophidion sperm activation and morphology were investigated with the aim of explaining the apparent lack of sperm competition in this syngnathid with externally brooding males. Nerophis ophidion sperm were activated by a mixture of ovarian fluid and sea water, but not by sea water alone. This indicated that sperm were not shed into the water but needed to be released near the eggs, which probably restrained sperm competition. (c) 2006 The Fisheries Society of the British Isles.
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| 3. |
- Kolm, Niclas, et al.
(author)
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Do egg size and parental care coevolve in fish?
- 2005
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 66:6, s. 1499-1515
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Journal article (peer-reviewed)abstract
- A phenomenon that has attracted a substantial theoretical and empirical interest is the positive relationship between egg size and the extent of parental care in fishes. Interestingly, despite the effort put into solving the causality behind this relationship over the past two decades it remains largely unsolved. Moreover, how general the positive relationship between egg size and parental care is among fishes is also poorly understood. In order to stimulate research exploring egg size and parental care variation in fishes, the potential selective forces from both natural and sexual selection on egg size and parental care are discussed. Recent empirical findings on how oxygen requirements and developmental times may differ between differently sized eggs are incorporated into a critical view of the current theory of this field. Furthermore, it is suggested that the up to now neglected effects of sexual selection, through both mate choice and sexual conflict, can have strong effects on the relationship between egg size and parental care in fishes. In light of the recent developments of comparative and experimental methods, future approaches that may improve the understanding of the relationship between egg size and care in fishes are suggested.
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| 4. |
- Martin-Smith, K. M., et al.
(author)
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Growth hormone increases growth and dominance of wild juvenile Atlantic salmon without affecting space use
- 2004
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 65, s. 156-172
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Journal article (peer-reviewed)abstract
- Growth hormone (GH) was applied to Atlantic salmon Salmo salar parr (the pre-migratory freshwater life stage) to manipulate growth potential experimentally and to elucidate the effects on dominance status, actual growth, exploratory activity and home range. Experiments were conducted using seven groups of eight parr from May to September of two successive years. The fish were tagged with passive integrated transponders (PIT tags), tested for dominance, and then held in an enclosed section of a natural stream which was fitted with an array of PIT tag detectors to record space use at a definition of c. 2 m. Relationships between dominance rank, space use and growth were established over 2 weeks. The four lowest ranking fish in each group were then given a slow-release GH implant while the other fish received a placebo. The GH stimulated increase in fork length (L-F) and mass and decrease in condition factor due to the relatively greater increase in L-F. There was, however, an interaction between GH-stimulated increase in growth and season, with the hormone having an effect only during the early part of the summer. Regardless of treatment, fish that moved most around their home range grew fastest. Increased growth in GH-treated fish was associated with an increase in growth per unit movement, not increased total movement. This suggested that GH-treated fish increased their rate of short-distance (<2 m) foraging movements. Overall, space use, measured in terms of home range size and time allocation throughout the range, did not vary consistently in response to application of GH. There was a strong correlation between the weighted centre of the home range (a measure of position within the enclosure) before and after treatment, irrespective of whether fish were given GH or a placebo. The study shows that when density is low relative to carrying capacity, GH stimulates increased dominance and growth in a near-natural environment without having measurable effects on space use at a definition of e. 2 m. The results are interpreted as suggesting that high dominance status gives no significant growth advantage in a highly competitive situation, but increases foraging rate when food is abundant. Increased foraging appears to result from local changes in time budgeting rather than variations in the extent of home range and larger-scale movements within it. Thus, in areas with declining wild Atlantic salmon populations where the habitat is unsaturated and food is abundant, introduced domestic Atlantic salmon may be competitively superior. (C) 2004 Crown copyright.
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| 5. |
- Monteiro, N.M., et al.
(author)
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Reproductive migrations of the sex role reversed pipefish Nerophis lumbriciformis (Pisces;Syngnathidae)
- 2006
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 69:1, s. 66-74
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Journal article (peer-reviewed)abstract
- Using an individual identification technique, a population of worm pipefish Nerophis lumbriciformis was followed during 19 months, in order to determine the exact use of the intertidal and, considering the specific movement patterns of males and females, the mating system exhibited by this population. Field observations showed that the number of adults increased during the breeding season, with males arriving 1 month earlier than females. Furthermore, males and females presented distinct permanence periods, showing that the intertidal is used as a mating arena. It was also observed that both male and female worm pipefish mated repeatedly over the span of a reproductive season, but females exhibited shorter remating intervals. Also, females stayed for longer periods on the mating grounds, the intertidal zone, whereas males typically left for the subtidal after mating, usually returning within 2 months. These inter-sexual differences in the occupation of the intertidal suggest that females breed with different males but also that males accept eggs from various females since, on their return, a new group of mating partners was now available. Thus, N. lumbriciformis might be considered polygynandric. It is a clearly dimorphic species in spite of the observed polygynandry, suggesting that differences in remating intervals may be influential in determining the strength of sexual selection along with what may be expected from the polygynandrous mating system alone.
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| 6. |
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| 7. |
- Sundström, L. Fredrik, 1972, et al.
(author)
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Density-dependent growth in hatchery-reared brown trout released into a natural stream
- 2004
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 65:5, s. 1385-1391
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Journal article (peer-reviewed)abstract
- Hatchery-reared brown trout Salmo trutta stocked in a natural stream in addition to resident wild brown trout grew more slowly than those stocked with an experimentally reduced density of brown wild trout. In both cases, hatchery-reared brown trout grew more slowly than resident wild fish in control sections. Mortality and movements did not differ among the three categories of fish. The results showed that growth of stocked hatchery-reared brown trout parr was density-dependent, most likely as a consequence of increased competition. Thus, supplementary release of hatchery-reared fish did not necessarily increase biomass. (C) 2004 The Fisheries Society of the British Isles.
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| 8. |
- Svensson, Ola, 1971-, et al.
(author)
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Costly courtship or dishonest display? Intensely displaying sand goby males have lower lipid content
- 2004
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 64:5, s. 1425-1429
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Journal article (peer-reviewed)abstract
- Intensely displaying sand goby Pomatoschistus minutus males had lower lipid content, indicating that signalling increased energy expenditure, or that low condition males increased their signalling effort. Display intensity correlated positively with nest-defence and tended to correlate positively with filial cannibalism. (C) 2004 The Fisheries society of the British Isles.
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| 9. |
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| 10. |
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| 11. |
- Ahnesjö, Ingrid
(author)
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Behavioural temperature preference in a brooding male pipefish Syngnathus typhle
- 2008
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 73:4, s. 1039-1045
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Journal article (peer-reviewed)abstract
- In the broad-nosed pipefish Syngnathus typhle, brooding males positioned themselves significantly more often towards the warmer part (18 degrees C) of an aquarium. whereas females were indifferent in this respect. This behavioural temperature preference may increase male brooding rate and indirectly influence patterns of mating competition. (c) 2008 The Author Journal compilation (c) 2008 The Fisheries Society of the British Isles.
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| 12. |
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| 13. |
- Ahnesjö, Ingrid
(author)
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Seahorses and Their Relatives
- 2010
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 77:1, s. 308-309
-
Review (other academic/artistic)
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| 14. |
- Amcoff, Mirjam, et al.
(author)
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Does female feeding motivation affect the response to a food-mimicking male ornament in the swordtail characin Corynopoma riisei?
- 2013
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 83:2, s. 343-354
-
Journal article (peer-reviewed)abstract
- Female response to various aspects of male trait morphology and the effect of female feeding motivation were investigated in the swordtail characin Corynopoma riisei, a species where males are equipped with a flag-like food-mimicking ornament that grows from the operculum. Unfed females responded more strongly to the male ornament and showed a stronger preference for larger ornaments than did fed females. Females were shown not to discriminate between artificial male ornaments of either undamaged or damaged shape.
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| 15. |
- Amcoff, P., et al.
(author)
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Alterations of dopaminergic and serotonergic activity in the brain of sea-run Baltic salmon suffering a thiamine deficiency-related disorder
- 2002
-
In: Journal of Fish Biology. - : Elsevier. - 0022-1112 .- 1095-8649. ; 60:6, s. 1407-1416
-
Journal article (peer-reviewed)abstract
- Baltic salmon Salmo salar females displaying wiggling behaviour had significantly lower (P<0.05) hepatic and ovarian thiamine (vitamin B1) concentrations than the normal females, confirming that they suffered from a thiamine deficiency. A significantly (P<0.05) increased monoaminergic activity was found in the telencephalon and the hypothalamus of the wiggling individuals as indicated by [5-hydroxyindoleacetic acid (5-HIAA)]: [5-hydroxytryptamine (5-HT)] and [3,4-dihydroxyphenylacetic acid (DOPAC)]: [dopamine (DA)] ratios. The 5-HIAA concentrations of wiggling individuals were significantly (P<0.05) higher in the telencephalon and the hypothalamus compared to normal fish. Wiggling fish showed significantly (P<0.05) higher concentrations of the DA metabolite DOPAC in the hypothalamus and the brain stem compared to normal fish. Furthermore, the brain stem in wiggling fish contained significantly (P<0.05) less 5-HT than in normal individuals, which was also reflected in a significant (P<0.05) increase in the (5-HIAA): (5-HT) ratio. These results demonstrate an increased serotonergic and dopaminergic activity in wiggling compared to normal fish. The altered monoaminergic activity may be directly related to altered brain thiamine metabolism, but a general stress caused by thiamine deficiency and an inability to regulate swim bladder inflation may contribute. Furthermore, a changed brain monoaminergic activity may contribute to the behaviour characterizing wiggling fish.
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| 16. |
- Andersson, Matilda L., et al.
(author)
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Chasing away accurate results : exhaustive chase protocols underestimate maximum metabolic rate estimates in European perch Perca fluviatilis
- 2020
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 97:6, s. 1644-1650
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Journal article (peer-reviewed)abstract
- Metabolic rates are one of many measures that are used to explain species' response to environmental change. Static respirometry is used to calculate the standard metabolic rate (SMR) of fish, and when combined with exhaustive chase protocols it can be used to measure maximum metabolic rate (MMR) and aerobic scope (AS) as well. While these methods have been tested in comparison to swim tunnels and chambers with circular currents, they have not been tested in comparison with a no‐chase control. We used a repeated‐measures design to compare estimates of SMR, MMR and AS in European perch Perca fluviatilis following three protocols: (a) a no‐chase control; (b) a 3‐min exhaustive chase; and (c) a 3‐min exhaustive chase followed by 1‐min air exposure. We found that, contrary to expectations, exhaustive chase protocols underestimate MMR and AS at 18°C, compared to the no‐chase control. This suggests that metabolic rates of other species with similar locomotorty modes or lifestyles could be similarly underestimated using chase protocols. These underestimates have implications for studies examining metabolic performance and responses to climate change scenarios. To prevent underestimates, future experiments measuring metabolic rates should include a pilot with a no‐chase control or, when appropriate, an adjusted methodology in which trials end with the exhaustive chase instead of beginning with it.
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| 17. |
- Arnason, T., et al.
(author)
-
Long-term rearing of Arctic charr Salvelinus alpinus under different salinity regimes at constant temperature
- 2014
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112. ; 85:4, s. 1145-1162
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Journal article (peer-reviewed)abstract
- Arctic charr Salvelinus alpinus of the Holar strain (mean+/- s. e. body mass= 152.1+/-3.1g) were reared at four different salinity regimes at a constant temperature of 7.4 degrees C. Two groups were given a three-month acclimation in salinity 18 before the salinity was increased to either 25 or 29 (groups called A25 and A29), and two groups were reared in salinities 25 or 29 over the full experimental period of 409 days (groups called F25 and F29). In the first 3months, the A25 and A29 groups had the highest growth rates. By October 2011, there were no significant differences (two-way nested ANOVA, P> 0.05) in the mean body masses among A25, F25 and F29 (c. 1450 g), whereas A29 had a lower mean mass (1282 g). The growth in the last period from October 2011 to January 2012 was reduced by sexual maturation in the highest salinity regimes (A29 and F29), whereas fish in groups A25 and F25 showed high growth throughout the study. Males in all salinity groups had higher growth rates than females for the most part of the study, but the divergence between the sexes was most pronounced in the highest salinity regimes. All salinity groups showed distinct changes in Na+, K+-ATPase activity, with high activity in spring and summer, and lower activity in the autumn. Plasma sodium (Na+) levels were stable indicating that none of the experimental groups had problems in maintaining hydromineral balance during the study. While plasma leptin levels were not affected by salinity regimes, it was noted that these levels were 13-30% higher in fish with empty guts compared with those having food in their gut at the time of sampling. This suggests a link between leptin levels and food intake, indicating that this hormone may play a role in food intake and energy allocation in fishes.
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| 18. |
- Bakke-McKellep, A. M., et al.
(author)
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Effects of dietary soybean meal and photoperiod cycle on osmoregulation following seawater exposure in Atlantic salmon smolts
- 2006
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 69:5, s. 1396-1426
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Journal article (peer-reviewed)abstract
- Atlantic salmon Salmo salar juveniles were fed either fishmeal-based diets (FM) or diets in which soybean meal (SBM) partly replaced the FM from first feeding on. The fish were kept at continuous daylight during the juvenile stage. During the last 3 weeks before reaching 100 g body mass, all fish were subjected to 12L:12D. Starting at 100 g body mass, groups of 60 fish from each feeding background were subjected to continuous light for 12 weeks (short winter), or a square-wave photoperiod cycle to stimulate parr to smolt transformation with 8L:16D during the first 6 weeks, and then continuous light during the last 6 weeks (long winter). After the 12 weeks, 20 fish from each treatment were subjected to 0, 24 or 96 h seawater exposure at a water salinity of 34. Hypo-osmoregulatory ability at seawater exposure was assessed by mortality, intestinal pathology, plasma ion concentrations and osmolality, gill Na+/K+-ATPase activity and element concentrations in the cytoplasm of distal intestinal enterocytes using X-ray microanalysis. The hypo-osmoregulatory capacity was higher in fish kept at short winter than at long winter, apparently due to more rapid development of gill Na+/K+-ATPase activity. Fish fed SBM suffered typical soybean meal-induced histological alterations of the distal intestine and apparent reductions in digestive function in the more proximal gastrointestinal regions. The net osmoregulatory capacity of these fish was maintained, as indicated by higher gill Na+/K+-ATPase activity and lower plasma Na+, Ca2+ and osmolality compared to the FM-fed fish. Thus, feeding SBM did not impair the hypo-osmoregulatory ability of the Atlantic salmon following seawater exposure.
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| 19. |
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| 20. |
- Bass, Nathan Charles, et al.
(author)
-
Residency and movement patterns of adult Port Jackson sharks (Heterodontus portusjacksoni) at a breeding aggregation site
- 2021
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 99:4, s. 1455-1466
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Journal article (peer-reviewed)abstract
- Examining the movement ecology of mesopredators is fundamental to developing an understanding of their biology, ecology and behaviour, as well as the communities and ecosystems they influence. The limited research on the residency and movements of benthic marine mesopredators has primarily used visual tags, which do not allow for the efficient and accurate monitoring of individual space use. In this study, the authors investigated the residency and movement patterns of Port Jackson sharks Heterodontus portusjacksoni (Meyer 1793) at a breeding aggregation site in Jervis Bay, south-eastern Australia, using passive acoustic telemetry to further our understanding of the movement ecology of these important mesopredators. Between 2012 and 2014, individuals were tagged with acoustic transmitters, and their residency and movements within the bay were monitored for up to 4 years. H. portusjacksoni showed strong preferences for particular reefs within and between breeding seasons. Males had significantly higher residency indices at their favoured sites relative to females, suggesting that males may be engaging in territorial behaviour. Conversely, female H. portusjacksoni exhibited higher roaming indices relative to males indicating that females may move between sites to assess males. Finally, H. portusjacksoni showed temporal variation in movements between reefs with individuals typically visiting more reefs at night relative to the day, dusk and dawn corresponding with their nocturnal habits.
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| 21. |
- Behrens, J. W., et al.
(author)
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The parasitic copepod Lernaeocera branchialis negatively affects cardiorespiratory function in Gadus morhua
- 2014
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 84:5, s. 1599-1606
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Journal article (peer-reviewed)abstract
- The parasitic copepod Lernaeocera branchialis had a negative effect on cardiorespiratory function in Atlantic cod Gadus morhua such that it caused pronounced cardiac dysfunction with irregular rhythm and reduced stroke amplitude compared with uninfected fish. In addition, parasite infection depressed the postprandial cardiac output and oxygen consumption.
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| 22. |
- Bergek, Sara, et al.
(author)
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Panmixia in Zoarces viviparus: implications for environmental monitoring studies
- 2012
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 80, s. 2302-2316
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Journal article (peer-reviewed)abstract
- In this study, the genetic population structure of the eelpout Zoarces viviparus was investigated by using microsatellites. Samples were collected at 10 sites in the Baltic Sea, covering a distance of c. 90 km. Ten newly developed microsatellite loci were used to infer the population structure. No global spatial genetic differentiation was found (global F-ST = 0.0001; D-est = -0.0003), indicating strong gene flow at this scale, nor any clear pattern of isolation by distance. The results suggest that gene flow among the studied populations of Z. viviparus is stronger than usually thought, which might be caused by environmental homogeneity. This is important for planning and evaluating monitoring activities in this species and for the interpretation of ecotoxicological studies. Strong migration might lead to wrong conclusions concerning the pollution in a given area. Therefore, reference stations should be placed at a larger distance than presently practiced.
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| 23. |
- Bergek, Sara, 1979-, et al.
(author)
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Population differentiation in perch Perca fluviatilis : environmental effects on gene flow?
- 2010
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 76:5, s. 1159-1172
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Journal article (peer-reviewed)abstract
- Environmental parameters were used to investigate barriers to gene flow and genetic differentiation in the Eurasian perch (Perca fluviatilis L.) at a small geographical scale in an archipelago system. Significant genetic differentiation was found among locations. Distance per se did not play a major role in the reduction of gene flow. Instead, the largest genetic differences between populations correlated with major changes in environmental conditions, such as temperature at time of spawning. The results show that genetic divergence can arise between populations in habitats thought to be highly connected, and that environmental variables can influence the level of gene flow between populations, including those that are at small spatial scales (tens of kilometres). The importance of a landscape approach when investigating genetic differentiation and defining barriers to gene flow is highlighted.
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| 24. |
- Bergendahl, I. Ahlbeck, et al.
(author)
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Feeding range of age 1+year Eurasian perch Perca fluviatilis in the Baltic Sea
- 2017
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 90:5, s. 2060-2072
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Journal article (peer-reviewed)abstract
- Using the widespread Eurasian perch Perca fluviatilis as a model organism, feeding ranges were investigated using stable-isotope ratios (N-15 and C-13) and body condition. Differences were found between closely located sampling sites in a littoral area without obvious migration barriers, indicating that individual fish had small feeding ranges. Body condition differences between sampled stations were consistent over 4 years. Such sedentary behaviour is important to consider in, e.g. fisheries management and environmental monitoring, as local catch regulations may be meaningful or geographic stability in sampling locations may reduce noise in data.
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| 25. |
- Beveridge, M. C. M., et al.
(author)
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Meeting the food and nutrition needs of the poor : the role of fish and the opportunities and challenges emerging from the rise of aquaculture
- 2013
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 83:4, s. 1067-1084
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Journal article (peer-reviewed)abstract
- People who are food and nutrition insecure largely reside in Asia and Sub-Saharan Africa and for many, fish represents a rich source of protein, micronutrients and essential fatty acids. The contribution of fish to household food and nutrition security depends upon availability, access and cultural and personal preferences. Access is largely determined by location, seasonality and price but at the individual level it also depends upon a person's physiological and health status and how fish is prepared, cooked and shared among household members. The sustained and rapid expansion of aquaculture over the past 30years has resulted in >40% of all fish now consumed being derived from farming. While aquaculture produce increasingly features in the diets of many Asians, it is much less apparent among those living in Sub-Saharan Africa. Here, per capita fish consumption has grown little and despite the apparently strong markets and adequate biophysical conditions, aquaculture has yet to develop. The contribution of aquaculture to food and nutrition security is not only just an issue of where aquaculture occurs but also of what is being produced and how and whether the produce is as accessible as that from capture fisheries. The range of fish species produced by an increasingly globalized aquaculture industry differs from that derived from capture fisheries. Farmed fishes are also different in terms of their nutrient content, a result of the species being grown and of rearing methods. Farmed fish price affects access by poor consumers while the size at which fish is harvested influences both access and use. This paper explores these issues with particular reference to Asia and Africa and the technical and policy innovations needed to ensure that fish farming is able to fulfil its potential to meet the global population's food and nutrition needs.
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| 26. |
- Björklund, Mats, et al.
(author)
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Genetic differentiation in pikeperch (Sander lucioperca): the relative importance of gene flow, drift and common history
- 2007
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In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 71:Suppl B, s. 264-278
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Journal article (peer-reviewed)abstract
- To investigate the relative importance of homogenizing factors, such as gene flow, and diversifying factors, such as drift, genetic variation in pikeperch (Sander lucioperca) in two Fennoscandian regions (North and South) was analysed with microsatellites. Allelic richness and the degree of differentiation were significantly higher in the North (FST = 0·20) than in the South (FST = 0·064). In northern areas, assignments of genotypes were almost exclusively to the population of origin, but in southern areas, the proportion of correct assignments was significantly lower. Most samples exhibited significant heterozygote deficits, and the level of relatedness was higher than expected from randomness. These combined results suggest that there has been more gene flow between populations in southern areas than in northern areas, where the importance of genetic drift has been greater. Effective population sizes were small (c. 100) and did not differ between areas. The effect of a common history appears minor, and thus processes such as genetic drift and gene flow have been more influential in shaping the patterns of genetic diversity in this species.
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| 27. |
- Blyth, Samuel, et al.
(author)
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After the spawn and on the hook : Sea trout Salmo trutta biophysical responses to different components of catch and release in a coastal fishery
- 2022
-
In: Journal of Fish Biology. - : John Wiley & Sons. - 0022-1112 .- 1095-8649. ; 101:3, s. 464-477
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Journal article (peer-reviewed)abstract
- This study investigated the biophysical responses of sea run brown trout Salmo trutta to catch-and-release in the coastal fishery around Gotland, Sweden. It used information recorded on individual angled S. trutta (n = 162), including fight time, handling time, total air exposure time, injury, bleeding, fish length, body condition, spawning status, water temperature, hook location and difficulty of hook removal. Reflex action mortality predictors (equilibrium, operculum beats, tail grab response, body flex response and vestibular-ocular response), tests of blood glucose and lactate, and observation of hooking injury were used to measure the relative impact of the angling event on the fish's physical state and stress experienced. The results of this study suggest low rates of post-release mortality and generally limited stress responses to angling events, and relatively high post-release survival supported by the recapture of many tagged S. trutta. However, a number of scenarios were identified in which stress responses are likely to be compounded and where anglers should take additional action to reduce sublethal physiological disturbances and the risk of delayed mortality. Particular care should be taken to limit cumulative total air exposure to <10 s, and to reduce handling time and risk of additional injury in angling events with extended fight times, when water temperatures >10 degrees C, or where S. trutta show evidence of being physically compromised by injury or having recently spawned. The results also indicate the importance of using appropriately sized single hooks rather than larger treble hooks to reduce hooking injury and handling time during unhooking.
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| 28. |
- Brännäs, Eva, et al.
(author)
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Behaviour, physiology and carotenoid pigmentation in Arctic charr Salvelinus alpinus
- 2014
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 84, s. 1-9
-
Journal article (peer-reviewed)abstract
- The behaviour during an exploration task and the response to a confinement stress of Arctic charr Salvelinus alpinus were evaluated. Behaviour of individuals during 90 min of exploration was classified into high and low activity. High-activity individuals had higher plasma cortisol levels following stress compared to low-activity individuals. This indicates that high- and low-activity individuals correspond to reactive and proactive stress-coping styles. Further, a pigmentation analysis showed that high-activity individuals had a higher number of carotenoid spots cm(-2) than low-activity individuals. Thus, carotenoid pigmentation, as melanin pigmentation in other salmonids, could be linked to stress-coping style in S. alpinus. (C) 2013 The Fisheries Society of the British Isles
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| 29. |
- Brännäs, Eva, et al.
(author)
-
Proof of concept: visual categorization of carotenoid pigmentation in Arctic charr (Salvelinus alpinus L) can predict stress response
- 2021
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 98, s. 1192-1195
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Journal article (peer-reviewed)abstract
- Carotenoid pigmentation in Salvelinus alpinus has been connected to stress responsiveness in earlier studies. This has, however, only been tested with time-consuming image analysis from photos. Here, we used quick visual categorization of carotenoid pigmentation to investigate the stress responsiveness of the extreme groups. The visually selected charr were then exposed to a net restraint stressor. Arctic charr with few spots also had a lower stress responsiveness compared to charr with many spots. Thus, visual selection could be used as a simple method within aquaculture.
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| 30. |
- Brännäs, Eva
(author)
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Time-place learning and leader-follower relationships in Arctic charr Salvelinus alpinus
- 2014
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 84, s. 133-144
-
Journal article (peer-reviewed)abstract
- Feeding activity from a larger refuge site into two visually separated feeding sites with temporally restricted food availability, one in the morning and one in the evening were studied in duplicate groups of Arctic charr (Salvelinus alpinus L.). A pit-tag system enabled continuous monitoring of individual movements between the sites. Both groups synchronised their diel pattern of visit activity to the two feeding sites when food was available. One group showed a significant anticipatory visit activity into both feeding sites during the hours before the feed was available, suggesting a time and place learning of resource availability. The anticipatory activity of the other group was, however, less pronounced and only occurred into one of the feeding sites. Individual S. alpinus entered the feeding sites independently and no obvious patterns of leaders and followers were identified. All S. alpinus gained mass and moved between a refuge and the feeding sites. Different strategies of how individual S. alpinus utilized the feeding sites were not correlated with growth.
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| 31. |
- Carlsson, J., et al.
(author)
-
Microsatellites reveal fine-scale genetic structure in stream-living brown trout
- 1999
-
In: Journal of Fish Biology. - : John Wiley & Sons. - 0022-1112 .- 1095-8649. ; 55:6, s. 1290-1303
-
Journal article (peer-reviewed)abstract
- Multilocus F(ST) estimates revealed a pronounced genetic structure at six microsatellite loci in brown trout Salmo trutta in Nordre Finnvikelv, with at least three breeding units that remained stable over time. Significant differences in allele frequencies were found between five sections within a 3-km range, even when no physical barriers prevented fish from migrating between sections. It is argued that geological structures may rise to patterns resembling isolation by distance. Seemingly, the most important factor causing genetic differentiation in Nordre Finnvikelv is genetic drift in small populations that are geologically subdivided by a tributary and by impassable waterfalls. Some correlation between previous behavioural observations and genetic structures were found.
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| 32. |
- Chapman, Ben, et al.
(author)
-
Partial migration in fishes: causes and consequences.
- 2012
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 81:2, s. 456-478
-
Journal article (peer-reviewed)abstract
- Partial migration, where only some individuals from a population migrate, has been widely reported in a diverse range of animals. In this paper, what is known about the causes and consequences of partial migration in fishes is reviewed. Firstly, the ultimate and proximate drivers of partial migration are reflected upon: what ecological factors can shape the evolution of migratory dimorphism? How is partial migration maintained over evolutionary timescales? What proximate mechanisms determine whether an individual is migratory or remains resident? Following this, the consequences of partial migration are considered, in an ecological and evolutionary context, and also in an applied sense. Here it is argued that understanding the concept of partial migration is crucial for fisheries and ecosystem managers, and can provide information for conservation strategies. The review concludes with a reflection on the future opportunities in this field, and the avenues of research that are likely to be fruitful to shed light on the enduring puzzle of partial migration in fishes.
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| 33. |
- Chapman, Ben, et al.
(author)
-
Partial migration in fishes: definitions, methodologies and taxonomic distribution.
- 2012
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 81:2, s. 479-499
-
Journal article (peer-reviewed)abstract
- Partial migration, where populations are composed of both migratory and resident individuals, is extremely widespread across the animal kingdom. Researchers studying fish movements have long recognized that many fishes are partial migrants, however, no detailed taxonomic review has ever been published. In addition, previous work and synthesis has been hampered by a varied lexicon associated with this phenomenon in fishes. In this review, definitions and important concepts in partial migration research are discussed, and a classification system of the different forms of partial migration in fishes introduced. Next, a detailed taxonomic overview of partial migration in this group is considered. Finally, methodological approaches that ichthyologists can use to study this fascinating phenomenon are reviewed. Partial migration is more widespread amongst fishes than previously thought, and given the array of techniques available to fish biologists to study migratory variation the future of the field looks promising.
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| 34. |
- Charlier, Johan, et al.
(author)
-
Census (NC) and genetically effective (Ne) population size in a lake-resident population of brown trout Salmo trutta
- 2011
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 79:7, s. 2074-2082
-
Journal article (peer-reviewed)abstract
- Census (NC) and effective population size (Ne) were estimated for a lake-resident population of brown trout Salmo trutta as 576 and 63, respectively. The point estimate of the ratio of effective to census population size (Ne:NC) for this population is 0·11 with a range of 0·06–0·26, suggesting that Ne:NC ratio for lake-resident populations agree more with estimates for fishes with anadromous life histories than the small ratios observed in many marine fishes
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| 35. |
- Clark, T.D., et al.
(author)
-
Calibration of a hand-held haemoglobin analyser for use on fish blood
- 2008
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 73:10, s. 2587-2595
-
Journal article (peer-reviewed)abstract
- The HemoCue haemoglobin analyser consistently overestimated haemoglobin concentration ([Hb]) in the blood of all fish species (sockeye salmon Oncorhynchus nerka, Chinook salmon Oncorhynchus tshawytscha, Pacific bluefin tuna Thunnus orientalis and chub mackerel Scomber japonicus) by 22–50% (9·9–36·0 g l−1) over a [Hb] range of 20–160 g l−1. The systematic nature of the overestimation, however, allowed the formulation of an accurate calibration equation that can be used to correct values of [Hb] measured by the HemoCue in field studies.
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| 36. |
- Clevestam, P. D., et al.
(author)
-
Too short to spawn? : Implications of small body size and swimming distance on successful migration and maturation of the European eel Anguilla anguilla
- 2011
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 78:4, s. 1073-1089
-
Journal article (peer-reviewed)abstract
- Individual net fat reserves after migration and reproductive investments were calculated for migrating female silver eels Anguilla anguilla (n = 387) collected in the outlet region of the Baltic Sea during the autumn run. It is estimated that 20 center dot 4% of the A. anguilla had completely exhausted all initial fat reserves and that 45 center dot 0% of A. anguilla were within 90% of complete energy depletion after migration and reproduction. This study concludes that a combination of body size and distance (6900 km) to the spawning area in the Sargasso Sea explains the results. An increase in the costs of migration due to heavy infection with Anguillicoloides crassus was also evaluated in an additional scenario with results showing that 26 center dot 4% of the A. anguilla had completely depleted all fat reserves. It is hypothesized that a large proportion of female silver A. anguilla from the Baltic Sea catchment area will have inadequate or suboptimal reserves for successful migration and reproduction.
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| 37. |
- Conrad, J L, et al.
(author)
-
Behavioural syndromes in fishes : a review with implications for ecology and fisheries management
- 2011
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 78:2, s. 395-435
-
Journal article (peer-reviewed)abstract
- This review examines the contribution of research on fishes to the growing field of behavioural syndromes. Current knowledge of behavioural syndromes in fishes is reviewed with respect to five main axes of animal personality: (1) shyness-boldness, (2) exploration-avoidance, (3) activity, (4) aggressiveness and (5) sociability. Compared with other taxa, research on fishes has played a leading role in describing the shy-bold personality axis and has made innovative contributions to the study of the sociability dimension by incorporating social network theory. Fishes are virtually the only major taxon in which behavioural correlations have been compared between populations. This research has guided the field in examining how variation in selection regime may shape personality. Recent research on fishes has also made important strides in understanding genetic and neuroendocrine bases for behavioural syndromes using approaches involving artificial selection, genetic mapping, candidate gene and functional genomics. This work has illustrated consistent individual variation in highly complex neuroendocrine and gene expression pathways. In contrast, relatively little work on fishes has examined the ontogenetic stability of behavioural syndromes or their fitness consequences. Finally, adopting a behavioural syndrome framework in fisheries management issues including artificial propagation, habitat restoration and invasive species, may promote restoration success. Few studies, however, have examined the ecological relevance of behavioural syndromes in the field. Knowledge of how behavioural syndromes play out in the wild will be crucial to incorporating such a framework into management practices.
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| 38. |
- Cooke, Steven J., et al.
(author)
-
Searching for responsible and sustainable recreational fisheries in the Anthropocene
- 2019
-
In: Journal of Fish Biology. - : John Wiley & Sons. - 0022-1112 .- 1095-8649. ; 94:6, s. 845-856
-
Journal article (peer-reviewed)abstract
- Recreational fisheries that use rod and reel (i.e., angling) operate around the globe in diverse freshwater and marine habitats, targeting many different gamefish species and engaging at least 220 million participants. The motivations for fishing vary extensively; whether anglers engage in catch-and-release or are harvest-oriented, there is strong potential for recreational fisheries to be conducted in a manner that is both responsible and sustainable. There are many examples of recreational fisheries that are well-managed where anglers, the angling industry and managers engage in responsible behaviours that both contribute to long-term sustainability of fish populations and the sector. Yet, recreational fisheries do not operate in a vacuum; fish populations face threats and stressors including harvest from other sectors as well as environmental change, a defining characteristic of the Anthropocene. We argue that the future of recreational fisheries and indeed many wild fish populations and aquatic ecosystems depends on having responsible and sustainable (R&S) recreational fisheries whilst, where possible, addressing, or at least lobbying for increased awareness about the threats to recreational fisheries emanating from outside the sector (e.g., climate change). Here, we first consider how the concepts of R&S intersect in the recreational fishing sector in an increasingly complex socio-cultural context. Next, we explore the role of the angler, angling industry and decision-makers in achieving R&S fisheries. We extend this idea further by considering the consequences of a future without recreational fisheries (either because of failures related to R&S) and explore a pertinent case study situated in Uttarakahand, India. Unlike other fisheries sectors where the number of participants is relatively small, recreational angling participants are numerous and widespread, such that if their actions are responsible, they have the potential to be a key voice for conservation and serve as a major force for good in the Anthropocene. What remains to be seen is whether this will be achieved, or if failure will occur to the point that recreational fisheries face increasing pressure to cease, as a result of external environmental threats, the environmental effects of recreational fishing and emerging ethical concerns about the welfare of angled fish.
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| 39. |
- Cucherousset, J., et al.
(author)
-
Growth-enhanced salmon modify stream ecosystem functioning
- 2021
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 99:6, s. 1978-1989
-
Journal article (peer-reviewed)abstract
- Use of fast-growing domesticated and/or genetically modified strains of fish is becoming increasingly common in aquaculture, increasing the likelihood of deliberate or accidental introductions into the wild. To date, their ecological impacts on ecosystems remain to be quantified. Here, using a controlled phenotype manipulation by implanting growth hormone in juvenile Atlantic salmon (Salmo salar), we found that growth-enhanced fish display changes in several phenotypic traits known to be important for ecosystem functioning, such as habitat use, morphology and excretion rate. Furthermore, these phenotypic changes were associated with significant impacts on the invertebrate community and key stream ecosystem functions such as primary production and leaf-litter decomposition. These findings provide novel evidence that introductions of growth-enhanced fish into the wild can affect the functioning of natural ecosystems and represent a form of intraspecific invasion. Consequently, environmental impact assessments of growth-enhanced organisms need to explicitly consider ecosystem-level effects.
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| 40. |
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| 41. |
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| 42. |
- Delling, Bo, et al.
(author)
-
Museomics reveals the phylogenetic position of the extinct Moroccan trout Salmo pallaryi
- 2023
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 102:3, s. 619-627
-
Journal article (peer-reviewed)abstract
- The authors used museomics to reconstruct the mitochondrial genome from two individuals of the Moroccan, endemic and extinct trout, Salmo pallaryi. They further obtained partial data from 21 nuclear genes previously used for trout phylogenetic analyses. Phylogenetic analyses, including publicly available data from the mitochondrial control region and the cytochrome b gene, and the 21 nuclear genes, place S. pallaryi among other North African trouts. mtDNA places S. pallaryi close to Salmo macrostigma within a single North African clade. Although the nuclear coverage of the genome was low, both specimens were independently positioned as sisters to one of two distantly related North African clades, viz. the Atlas clade with the Dades trout, Salmo multipunctatus. Phylogenetic discordance between mtDNA and nuclear DNA phylogenies is briefly discussed. As several specimens that were extracted failed to produce DNA of sufficient quality, the authors discuss potential reasons for the failure. They suggest that museum specimens in poor physical condition may be better for DNA extraction compared to better-preserved ones, possibly related to the innovation of formalin as a fixative before ethanol storage in the early 20th century.
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| 43. |
- Demandt, Marnie, et al.
(author)
-
Loss of genetic variability in reintroduced roach (Rutilus rutilus) populations
- 2007
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 70:Suppl.B, s. 255-261
-
Journal article (peer-reviewed)abstract
- Genetic variation at five microsatellite loci and in mtDNA was surveyed in reintroduced and 'control' populations of roach (Rutilus rutilus) in Sweden. Microsatellite allelic richness and allele size ranges were significantly reduced in reintroduced populations, and mtDNA diversity was nearly significantly reduced in reintroduced populations. These measures of genetic variability were strongly correlated with lake characteristics that influence population size and food availability.
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| 44. |
- Desforges, Jessica E., et al.
(author)
-
The ecological relevance of critical thermal maxima methodology for fishes
- 2023
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649.
-
Journal article (peer-reviewed)abstract
- Critical thermal maxima methodology (CTM) has been used to infer acute upper thermal tolerance in fishes since the 1950s, yet its ecological relevance remains debated. In this study, the authors synthesize evidence to identify methodological concerns and common misconceptions that have limited the interpretation of critical thermal maximum (CTmax; value for an individual fish during one trial) in ecological and evolutionary studies of fishes. They identified limitations of, and opportunities for, using CTmax as a metric in experiments, focusing on rates of thermal ramping, acclimation regimes, thermal safety margins, methodological endpoints, links to performance traits and repeatability. Care must be taken when interpreting CTM in ecological contexts, because the protocol was originally designed for ecotoxicological research with standardized methods to facilitate comparisons within study individuals, across species and contexts. CTM can, however, be used in ecological contexts to predict impacts of environmental warming, but only if parameters influencing thermal limits, such as acclimation temperature or rate of thermal ramping, are taken into account. Applications can include mitigating the effects of climate change, informing infrastructure planning or modelling species distribution, adaptation and/or performance in response to climate-related temperature change. The authors’ synthesis points to several key directions for future research that will further aid the application and interpretation of CTM data in ecological contexts.
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| 45. |
- Duan, M., et al.
(author)
-
Risk-taking behaviour may explain high predation mortality of GH-transgenic common carp Cyprinus carpio
- 2013
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 83:5, s. 1183-1196
-
Journal article (peer-reviewed)abstract
- The competitive ability and habitat selection of juvenile all-fish GH-transgenic common carp Cyprinus carpio and their size-matched non-transgenic conspecifics, in the absence and presence of predation risk, under different food distributions, were compared. Unequal-competitor ideal-free-distribution analysis showed that a larger proportion of transgenic C. carpio fed within the system, although they were not overrepresented at a higher-quantity food source. Moreover, the analysis showed that transgenic C. carpio maintained a faster growth rate, and were more willing to risk exposure to a predator when foraging, thereby supporting the hypothesis that predation selects against maximal growth rates by removing individuals that display increased foraging effort. Without compensatory behaviours that could mitigate the effects of predation risk, the escaped or released transgenic C. carpio with high-gain and high-risk performance would grow well but probably suffer high predation mortality in nature.
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| 46. |
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| 47. |
- Einarsdottir, Ingibjörg, 1951, et al.
(author)
-
Plasma growth hormone-binding protein levels in Atlantic salmon Salmo salar during smoltification and seawater transfer
- 2014
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112. ; 85:4, s. 1279-1296
-
Journal article (peer-reviewed)abstract
- Specific growth hormone (GH)-binding protein (Ghbp) was purified from Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss plasma with immunoprecipitation and characterized in cross-linking studies using autoradiography and western blots. The size of the Ghbp was estimated to be c. 53 kDa. A radioimmunoassay was established to measure Ghbp in salmonids, using antibodies specific against the extracellular segment of the S. salar growth hormone receptor 1 (grh1; GenBank AY462105). Plasma Ghbp levels were measured in S. salar smolts in fresh water and after transfer to seawater (SW; experiments 1 and 2), and in post-smolts kept at different salinities (0, 12, 22 and 34) for 3 months (experiment 3). A transient increase in plasma Ghbp, which lasted for 1 month or less, was noted in smolts after transfer to SW. Concomitantly, plasma GH and gill Na+-K+-ATPase activity increased during smoltification (in experiment 2). No difference in plasma Ghbp was evident between post-smolts kept at different salinities, although the fish kept at salinity 34 had higher plasma GH than the group kept at salinity 22 and higher hepatic ghr1 expression than post-smolts kept at salinity 12. This suggests that plasma Ghbp regulation may respond to salinity changes in the short term. The lack of correlation between Ghbp, plasma GH and hepatic ghr1 expression in the long-term post-smolt experiment indicates that Ghbp levels may be regulated independently of other components of the endocrine GH system in salmonids.
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| 48. |
- Eklöv, Peter, et al.
(author)
-
Pike predators induce morphological changes in young perch and roach
- 2007
-
In: Journal of Fish Biology. - : Wiley. - 0022-1112 .- 1095-8649. ; 70:1, s. 155-164
-
Journal article (peer-reviewed)abstract
- The morphological response of two 1 year-old prey species, perch Perca fluviatilis and roach Rutilus rutilus to the presence of predatory pike Esox lucius, was tested in a 6 week aquarium experiment. The growth of perch was higher than that of roach but there was no difference in growth of prey between predator and control treatments. The presence of pike caused morphological changes in both perch and roach. Perch showed an increase in body depth during the experiment whereas the morphological response of roach to pike was more related to a displacement of the dorsal and pelvic fins and width of the anal fin. Differences in morphological responses of perch and roach to pike can be interpreted by their overall differences in antipredator strategies.
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| 49. |
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| 50. |
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