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1
Wedderburn, S. D., C. M. Bice i T. C. Barnes. "Prey selection and diet overlap of native golden perch and alien redfin perch under contrasting hydrological conditions". Australian Journal of Zoology 62, nr 5 (2014): 374. http://dx.doi.org/10.1071/zo14018.
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Many freshwater fishes have been introduced outside their natural range. The consequences have included the decline or extinction of native fishes, principally due to competition and predation. Redfin perch (Perca fluviatilis) is a highly efficient predatory fish species that was introduced to Australia in the 1800s. It now has a broad distribution in the Murray–Darling Basin, but its impacts on native fishes are largely unstudied. It often cohabits with native golden perch (Macquaria ambigua ambigua), which is similar from a trophic ecomorphology perspective. We examine prey selection and diet overlap of adult redfin perch and golden perch under contrasting hydrological conditions in terminating lakes of the Murray–Darling Basin. Prey selection by both species varied substantially between drought and flood conditions. Diet overlap of redfin perch and golden perch was significant only during flood, and was apparently related to pelagic prey availability. There were dietary differences during drought that imply that resource partitioning occurred between the perches, possibly because competitive interactions were intensified. Conversely, the promotion of pelagic prey fishes during flooding apparently facilitated resource sharing. The findings suggest that redfin perch can directly compete with native piscivores for prey. The potential impacts on native piscivores and small-bodied fish populations warrant further experimental and field investigations.
2
Hrabik, Thomas R., John J. Magnuson i Ann S. McLain. "Predicting the effects of rainbow smelt on native fishes in small lakes: evidence from long-term research on two lakes". Canadian Journal of Fisheries and Aquatic Sciences 55, nr 6 (1.06.1998): 1364–71. http://dx.doi.org/10.1139/f98-032.
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We assessed predictability of negative interactions between native fishes and exotic rainbow smelt (Osmerus mordax) through field experiments and long-term data analysis for two lakes in Wisconsin. Predictions were made based on thermal preferences, diet characteristics, and published accounts of interactions between smelt and yellow perch (Perca flavescens) and smelt and cisco (Coregonus artedii). Our results indicate predation is the most likely cause for the extirpation of cisco from Sparkling Lake in 1990. In Crystal Lake, native yellow perch experienced significant overlap in distribution and diet with smelt. The condition of adult perch was negatively correlated with smelt abundance indicating competition was occurring. Smelt feed on a wide size range of prey items making this species a threat to native fishes, especially when spatial overlap is high. Information on spatial and temporal overlap and diet enable useful predictions about the effect of smelt invasions on native fishes.
3
Crowder, Larry B., Michael E. McDonald i James A. Rice. "Understanding Recruitment of Lake Michigan Fishes: The Importance of Size-Based Interactions Between Fish and Zoopiankton". Canadian Journal of Fisheries and Aquatic Sciences 44, S2 (19.12.1987): s141—s147. http://dx.doi.org/10.1139/f87-317.
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Mechanisms controlling recruitment of fishes appear to be strongly size dependent. It is now established that size-selective predators can dramatically reduce zooplankton size, but little is known about the effects of zooplankton size on growth and recruitment of fish through the post-larval stage. As fish grow, their optimal prey size increases; if large zooplankton are uncommon, growth rates may be reduced, prolonging vulnerability to predation or other size-dependent mortality sources and thus reducing recruitment. Most Lake Michigan fishes, including offshore species such as bloater (Coregonus hoyi) and nearshore species such as yellow perch (Perca flavescens), shift from feeding on zooplankton in their early years to feeding on benthic prey or to piscivory. Predation mortality on many larval and juvenile fishes including bloater and yellow perch has been shown to be size or growth rate dependent. As alewife (Alosa pseudoharengus) increased in abundance in Lake Michigan in the 1960s, large zooplankton declined and both bloater and perch recruitment was poor. In the late 1970s and early 1980s, alewife declined, large zooplankton increased, and strong year classes of bloater and perch were formed. Based on these dynamics and recent research on resource use, foraging behavior, and recruitment dynamics of larval and juvenile fishes, we suggest two hypotheses. First, young-of-year and juvenile pelagic fishes may have the major size-structuring effects on epilimnial zooplankton in Lake Michigan. And second, if large zooplankton are uncommon, as they were in Lake Michigan in the 1960s, growth rates and recruitment of native fishes will be reduced. Size-based interactions between fish and zooplankton appear to have important implications for growth and recruitment success of fishes.
4
Hilling, Corbin D., Nate D. Taylor, Stuart A. Welsh i Dustin M. Smith. "Population Characteristics of Yellow Perch in a Central Appalachia Hydropower Reservoir". Journal of Fish and Wildlife Management 9, nr 2 (17.08.2018): 486–95. http://dx.doi.org/10.3996/012018-jfwm-007.
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Abstract Estimates of population characteristics of sport fishes inform fisheries management decisions and provide feedback on management strategies. Cheat Lake provides an unusual fishery in West Virginia because the hydropower reservoir supports a Yellow Perch Perca flavescens population. We estimated age structure, size structure, condition, total instantaneous mortality, growth, and summer diet for Cheat Lake Yellow Perch based on electrofishing collections in 2012. From 302 individuals, we observed a maximum age of 9 y. Maximum age, average size, and growth of females in the sample exceeded those of males. Cheat Lake Yellow Perch scored low on the relative weight index, but generally exhibited faster growth than other populations, even when compared by sex. Estimated annual survival was 0.63 (95% CI = 0.51–0.78), which is comparable to other exploited populations. These data support the presence of an ontogenetic diet shift from consumption of zooplankton to macroinvertebrates and fishes as Yellow Perch age. This study is the first evaluation we are aware of on Yellow Perch population characteristics in West Virginia, providing baseline data to enhance management decisions and direct future studies.
5
Dembkowski, Daniel J., David W. Willis i Melissa R. Wuellner. "Synchrony in larval yellow perch abundance: the influence of the Moran Effect during early life history". Canadian Journal of Fisheries and Aquatic Sciences 73, nr 10 (październik 2016): 1567–74. http://dx.doi.org/10.1139/cjfas-2015-0310.
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Recruitment may vary substantially in fish populations, which can drive not only adult population characteristics but also the dynamics of fishes dependent on the species of interest and recreational fisheries for these species. However, spatiotemporal trends in population fluctuations and potential drivers of recruitment variability are poorly understood. Therefore, we used a long-term (2000–2014) data set to estimate the extent of spatial synchrony in larval abundance and factors influencing variability in recruitment of yellow perch (Perca flavescens). Contrary to the prevailing paradigm that spatial synchrony in population fluctuations (i.e., recruitment) is typically absent or occurs at small spatial scales (<50 km) for freshwater species, abundance of larval yellow perch was synchronous among spatially segregated systems across a geographic scale of at least 180 km. Additionally, variation in larval yellow perch density was influenced by spatially-correlated climatic and hydrological variables (indicative of the Moran Effect). Results ultimately broaden the scale at which factors were previously thought to influence recruitment of freshwater fishes and provide important insight to patterns and processes that structure yellow perch populations.
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Hanson, John Mark, i William C. Leggett. "Effect of Competition Between Two Freshwater Fishes on Prey Consumption and Abundance". Canadian Journal of Fisheries and Aquatic Sciences 43, nr 7 (1.07.1986): 1363–72. http://dx.doi.org/10.1139/f86-170.
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The effect of inter- and intraspecific competition on the type and quantity of food consumed by fish, and on the abundance of macroinvertebrate prey, was examined by manipulating densities of yellow perch (Perca flavescens) and pumpkinseed (Lepomis gibbosus) stocked into littoral zone enclosures at levels approximating 0.5, 1.0, and 2.0 times the measured total fish biomass on the littoral zone. In intraspecific competition experiments, neither species showed a change in the type of prey eaten (principally macroinvertebrates). The amount of food eaten by yellow perch reared at high (26 g/m2) densities was significantly depressed relative to that of perch reared at low (6.5 g/m2) and natural (13 g/m2) densities. There were no significant differences in the amount of food eaten by pumpkinseed at the three fish densities. The gut fullness of pumpkinseed reared at high densities, however, was biased to a significant but unknown degree by the inclusion of a nonfood item, macrophyte fragments, in the estimates. No other fish consumed macrophytes. In interspecific competition experiments, the gut fullness of yellow perch and pumpkinseed reared together (combined density 13 g/m2) did not differ from that of fish reared alone at low or natural densities. The diet (principally macroinvertebrates) of the superior competitor, pumpkinseed, did not change relative to that of pumpkinseed reared alone. The inferior competitor, yellow perch, exhibited a significant change in diet. Microcrustaceans (an energetically inferior food) comprised 30–53% of the diet (by weight) of yellow perch reared with pumpkinseed compared with < 1% of the diet of perch reared alone. Total macroinvertebrate biomass and abundance were unaffected by differences in fish biomass in the enclosures.
7
Confer, John L., i Linda M. O'Bryan. "Changes in Prey Rank and Preference by Young Planktivores for Short-Term and Long-Term Ingestion Periods". Canadian Journal of Fisheries and Aquatic Sciences 46, nr 6 (1.06.1989): 1026–32. http://dx.doi.org/10.1139/f89-133.
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Feeding by young planktivorous fishes (yellow perch, Perca flavescens, rainbow trout, Oncorhynchus mykiss, and lake trout, Salvelinus namaycush) was examined. Prey rank was determined by offering a swarm of one prey type and observing ingestion rates. During the initial feeding burst, larger prey generally ranked higher. During long-term feeding the largest prey, large Daphnia magna, generally declined in rank while the smallest prey, Diaptomus sicilis, increased to the highest or second highest rank. Prey preference was measured with fishes feeding in a swarm of mixed prey. Initially small rainbow trout and yellow perch selected for large Daphnia then switched to Diaptomus. For small rainbow trout this switch in prey preference paralleled the change in prey rank. For yellow perch, large Daphnia and Diaptomus provided essentially the same long-term ingestion rates. The nearly exclusive selection for Diaptomus during long-term feeding did not agree with prey rank based on caloric ingestion rates. Previous work has shown that yellow perch have a high growth efficiency on a diet of Diaptomus. Selection for Diaptomus suggests that fish can rank prey by nutritional quality as well as caloric ingestion rates.
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Hanson, John Mark, i William C. Leggett. "Experimental and Field Evidence for Inter- and Intraspecific Competition in Two Freshwater Fishes". Canadian Journal of Fisheries and Aquatic Sciences 42, nr 2 (1.02.1985): 280–86. http://dx.doi.org/10.1139/f85-035.
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Direct evidence for intra- and interspecific competition in fishes was obtained by manipulating populations of yellow perch (Perca flavescens) and pumpkinseed (Lepomis gibbosus) stocked into littoral zone enclosures. Stocking densities were above, below, and equal to measured littoral zone fish biomass. There were no significant differences in mean percent weight change at given densities among repeated experiments (each of 14-d duration). In experiments testing for intraspecific competition, all fish reared at low density gained weight, all fish reared at high density lost weight, and mean weight change at natural density did not differ from 0.0. In experiments testing for interspecific competition, growth of pumpkinseed did not differ from growth of pumpkinseed reared alone at equivalent densities whereas growth of yellow perch was depressed relative to growth of yellow perch reared alone at equivalent densities. These growth changes did not result from behavioural interactions. We conclude that (a) inter- and intraspecific competition for food is significant at natural fish densities and (b) pumpkinseed are superior to perch when competing for food. A marked reduction in yellow perch growth in Lake Memphremagog between 1972 and 1983, coincident with a major increase in pumpkinseed abundance, is consistent with these findings and our interpretations.
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Mirza, Reehan, i Douglas Chivers. "DO JUVENILE YELLOW PERCH USE DIET CUES TO ASSESS THE LEVEL OF THREAT POSED BY INTRASPECIFIC PREDATORS?" Behaviour 138, nr 10 (2001): 1249–58. http://dx.doi.org/10.1163/15685390152822201.
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AbstractThe mechanisms that drive the evolution of intraspecifc predation (cannibalism) are unclear. Many authors speculate that predators can make substantial gains in nutrition and reproductive output by consuming conspecifics. However, by consuming conspecifics, predators may risk decreasing their inclusive fitness by consuming kin or increasing the chances of pathogen transmission. In fishes intraspecific predation is typically observed when resource levels are low. During these periods it is important for prey fishes to be able to accurately assess their level of predation risk from cannibalistic conspecifics. Prey animals may be able to do this by using chemical cues available in the predator's diet. The last meal consumed by the predator may give important information for prey animals to assess predation risk. We exposed juvenile yellow perch, Perca flavescens, to chemical cues of adult perch fed a diet of either juvenile perch, spot tail shiners, Notropis hudsonius, swordtails, Xiphophorus helleri, or a control of distilled water. Spot tail shiners and juvenile perch commonly form mixed species shoals and are vulnerable to the same suite of predators. Swordtails do not co-occur with yellow perch or spot tail shiners. We found that juvenile perch increased shelter use significantly more when exposed to chemical cues of adult perch fed juvenile perch or spot tails, compared to adult perch fed swordtails or those exposed to distilled water. This suggests that the level of chemosensory assessment used by juvenile perch is quite sophisticated and that the antipredator response can be mediated by specific cues in the predator's diet. This study is the first to demonstrate a response of a fish to chemical cues from intraspecific predators. Future studies should examine the importance of predator diet cues in responses to chemical cues from intraspecific predators.
10
Parrish, Donna L., i F. Joseph Margraf. "Prey Selectivity by Age 0 White Perch (Morone americana) and Yellow Perch (Perca flavescens) in Laboratory Experiments". Canadian Journal of Fisheries and Aquatic Sciences 48, nr 4 (1.04.1991): 607–10. http://dx.doi.org/10.1139/f91-077.
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We conducted prey selectivity experiments by age 0 white perch (Morone americana) and yellow perch (Perca flavescens) in the laboratory. Lake Erie zooplankters were introduced into tanks where both fishes were in single and combined species assemblages. We identified and counted the introduced plankton samples and the contents of fish stomachs after the feeding period. Our results showed no differences in prey consumed within a fish species, whether in single or combined assemblages (ANOVA, p > 0.05). There were a few differences between white perch and yellow perch consumption of each prey taxa (ANOVA); however, the arrays of organisms eaten were not different (MANOVA, p > 0.01). We note that the majority of prey consumed were smaller taxa, which is counter to optimal foraging predictions in relation to prey size, but is consistent with other research on young planktivore prey selectivities.
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Boisclair, D., i W. C. Leggett. "The Importance of Activity in Bioenergetics Models Applied to Actively Foraging Fishes". Canadian Journal of Fisheries and Aquatic Sciences 46, nr 11 (1.11.1989): 1859–67. http://dx.doi.org/10.1139/f89-234.
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We used the Kitchell et al. (J. Fish. Res. Board Can. 34: 1922–1935) bioenergetics model and field derived estimates of growth and consumption rates to estimate the quantity of energy allocated to activity by 28 combinations of yellow perch (Perca flavescens) age class and population. Activity costs among populations ranged from 0 to 40% of the perch bioenergetics budget. We further evaluated the influence of activity rates on the food consumption estimates predicted by the Kitchell et al. model and the model proposed by Kerr (Can. J. Fish. Aquat. Sci. 39: 371–379). As suggested by Kerr, activity costs increased as food consumption increased. However, we found no significant relationship between predicted and observed food consumption estimates for either model. The magnitude of, and the among-population variance in, the quantity of energy allocated to activity is consistent with our hypothesis that this component of the bioenergetics budget of fishes has the potential to contribute meaningfully to the explanation of inter-population differences in perch growth and, by extension, to the variance in growth of other actively foraging fish species.
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Benoît, Pierre-Olivier, Beatrix E. Beisner i Christopher T. Solomon. "Growth rate and abundance of common fishes is negatively related to dissolved organic carbon concentration in lakes". Canadian Journal of Fisheries and Aquatic Sciences 73, nr 8 (sierpień 2016): 1230–36. http://dx.doi.org/10.1139/cjfas-2015-0340.
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Dissolved organic carbon (DOC) can limit food web productivity in lakes, potentially imposing resource limitation on fishes. We asked whether the abundance or early growth rate of three fish species was negatively related to DOC in 59 lakes in southern Quebec, Canada, where DOC concentrations ranged from 4 to 16 mg·L−1 for lakes containing walleye (Sander vitreum) and yellow perch (Perca flavescens) and from 2.6 to 9 mg·L−1 for lakes containing lake trout (Salvelinus namaycush). Estimates of abundance and growth rate were more precise for walleye and lake trout than for yellow perch because of differences in sample size. Abundance was negatively related to DOC for walleye and perhaps also for lake trout and yellow perch. Early growth rate was negatively related to DOC for walleye and lake trout, but not for yellow perch. These results support a growing body of literature suggesting that the productivity of fish populations may be negatively related to DOC concentrations in lakes.
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Clermont, Jason J., i Anthony S. Overton. "Tracking Ontogenentic Food Habits of Early Life Stages of White and Yellow Perch in Albemarle Sound, North Carolina". Journal of North Carolina Academy of Science 131, nr 1 (1.12.2015): 2–12. http://dx.doi.org/10.7572/2167-5872-131.1.2.
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Abstract White Perch (Morone americana) and Yellow Perch (Perca flavescens) are percid fishes common to the Albemarle Estuarine System (AES) in North Carolina. Both species have well established recreational and commercial fisheries in the AES. The juvenile stages of these two species commonly occur in the same areas and likely share food resources. We investigated the feeding habits of juvenile White Perch and Yellow Perch in the AES from June through October 2005. The diets of both species were made up entirely of aquatic invertebrates, with copepods and cladocerans contributing (>90% by number) to the diet of juvenile White Perch. Mysid shrimp and amphipods were the primary source of White Perch dietary weight. Juvenile White Perch exhibited a marked change in prey with increased size, switching from smaller pelagic prey (e.g., copepods and cladocerans) to larger epibenthic prey (e.g., mysid shrimp and amphipods). Amphipods also were the primary prey of juvenile Yellow Perch, which differs from the majority of published data on the diet of juvenile Yellow Perch. The results of this study also provide evidence of little dietary overlap between the species, which was primarily explained by the timing of spawning and the size differences between the two species.
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Guerrero III, Rafael. "Commercially Caught Freshwater Fishes in the Philippines: Status, Issues, and Recommendations". Transactions of the National Academy of Science and Technology 44, nr 2022 (styczeń 2023): 1–15. http://dx.doi.org/10.57043/transnastphl.2022.2568.
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The Philippines is endowed with 406,328 hectares of inland waters consisting of lakes, marshes, and reservoirs. In 2018, the production of inland fisheries in the country was 164,835 metric tons (3.8% of total fisheries production) with a value of PHP 5.8 billion. This study was conducted to determine the status of commercially caught freshwater fishes in major inland waters based on available data, literature, and information from key informants and personal observations, and identify issues and recommend strategies for the sustainability of such fishes. Results of the analyses showed that the top 10 commercially caught freshwater fishes in 2017 were tilapia (50%), carp (16.4%), mudfish (11.0%), Asiatic catfish (6.6%), gourami (5.0%), white goby (3.8%), Manila catfish (2.6%), climbing perch (2.4%), silver perch (1.7%), and freshwater sardine (1.5%). Between 2005 and 2017, the highest increases in production were for the freshwater sardine (+49.7%), Asiatic catfish (+41.6%), and carp (+32.5%) while the highest decreases were for the silver perch (-69.8%), white goby (-39.5%), and Manila catfish (-26.6%). There was an average annual increase of 4.2% in the production of the 10 fishes for 2005-2017. The tilapia, mudfish, Asiatic catfish, and climbing perch were found in all regions of the country while the carp, gourami, white goby, Manila catfish, and silver perch were found in most regions. The freshwater sardine, on the other hand, was only found in the Lake Taal of Region IV-A (CALABARZON). The major issues threatening the sustainability of freshwater fishes were identified as overfishing, water pollution, invasive fishes, and environmental degradation. Recommendations for addressing such issues include the imposition of a closed fishing season, strict implementation of water quality standards, firm enforcement of rules and regulations for foreign/exotic fishes, and the reforestation of denuded forests.
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Morozinska-Gogol, J. "A check-list of parasites of percid fishes (Actinopterygii: Percidae) from the estuaries of the Polish coastal zone". Helminthologia 45, nr 4 (1.12.2008): 196–203. http://dx.doi.org/10.2478/s11687-008-0039-7.
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AbstractThe present paper summarized data on parasites of percid fishes (Actinopterygii: Percidae), such as pike-perch, European perch and ruffe from estuaries of the Polish coastal zone are listed, based on published records and long-term surveys carried out by the author. Parasites are listed alphabetically, separately for each host and for each parasite group with notes on their location on the host and geographical distribution (with references). A total of 41 species (taxa) of parasites were recorded on pike-perch Sander lucioperca (6 Ciliophora, 1 Myxozoa, 1 Monogenea, 11 Digenea, 4 Cestoda, 6 Nematoda, 5 Acanthocephala, 1 Mollusca, 1 Hirudinea, 4 Copepoda and 1 Branchiura). European perch, Perca fluviatilis, harboured 60 parasites (6 Ciliophora, 4 Myxozoa, 1 Monogenea, 18 Digenea, 9 Cestoda, 10 Nematoda, 5 Acanthocephala, 1 Mollusca, 1 Hirudinea, 4 Copepoda and 1 Branchiura). Ruffe Gymnocephalus cernuus featured 43 parasites (1 Microsporidia, 7 Ciliophora, 3 Myxozoa, 1 Monogenea, 13 Digenea, 5 Cestoda, 8 Nematoda, 2 Acanthocephala, 1 Mollusca and 2 Copepoda).
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D’Arco, Brett D., Jeremy L. Farrell, Sandra A. Nierzwicki-Bauer i Charles W. Boylen. "Are the Condition, Growth and Diet of Yellow Perch (Perca flavescens) Different between the Three Major Basins of Lake George, New York?" Open Fish Science Journal 8, nr 1 (17.11.2015): 30–36. http://dx.doi.org/10.2174/1874401x01508010030.
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Gill netting was carried out at 25 sites in Lake George, New York to determine if interbasin differences of yellow perch (Perca flavescens) exist. Fish relative weight, growth and diet were analyzed for 267 yellow perch. Yellow perch are known to be omnivorous in the lake eating zooplankton, benthos and small fishes in both the littoral and pelagic waters. The length-weight relationship exhibited a significant difference amongst the Narrows, North and South basins for condition constants (p < 0.05). Relative weights were consistently found to be below the general target range and had significant differences between the basins. Growth models of fish caught in the three basins showed variation in growth of yellow perch. The yellow perch from the North basin exhibited allometric growth, while those in the South and Narrows displayed isometric growth. The diets of yellow perch between the basins also were found to be different. Previous studies have noted differences between the basins with respect to chlorophyll a, chemistry, and biota. This study provides evidence of differences in the fishery amongst the basins that follow similar, previously defined, differences in chemistry.
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Graeb, Brian DS, Tracy Galarowicz, David H. Wahl, John M. Dettmers i Mathew J. Simpson. "Foraging behavior, morphology, and life history variation determine the ontogeny of piscivory in two closely related predators". Canadian Journal of Fisheries and Aquatic Sciences 62, nr 9 (1.09.2005): 2010–20. http://dx.doi.org/10.1139/f05-112.
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The ontogeny of piscivory is an important process during the early life history of many fishes, and why ontogenetic patterns of closely related species vary is unclear. We experimentally evaluated the importance of several factors that can determine the switch to piscivory in two predators with different dietary ontogenies: walleye (Sander vitreus), a specialist piscivore, and yellow perch (Perca flavescens), a dietary generalist. We conducted growth and prey selection experiments across several sizes of both predators using fish, zooplankton, and benthic invertebrates as prey. Walleye exhibited piscivorous feeding behavior throughout all size classes (2080 mm), whereas yellow perch were generalist predators, showing negative to neutral selection for fish prey and lower growth than walleye when feeding on fish. Walleye foraged more efficiently than yellow perch on all prey types, in part because gape widths of walleye increased more quickly with size. Bioenergetic model simulations showed that walleye grew slower than yellow perch when the proportion of fish was low in diets, but walleye growth was faster than yellow perch on a diet dominated by fish. Feeding behavior, morphology, and life history patterns likely work in combination, allowing walleye to switch to piscivory earlier than yellow perch.
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Searle, Peter C., Joshua A. Verde i Mark C. Belk. "Food Web Structure Informs Potential Causes of Bimodal Size Structure in a Top Predator". Open Fish Science Journal 11, nr 1 (18.09.2018): 36–45. http://dx.doi.org/10.2174/1874401x01811010036.
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Background: Assemblages of fishes in lakes and reservoirs in the western USA are dominated by non-native, large-bodied, piscivorous fishes that lack a shared evolutionary history. Top predators in these crowded systems are often characterized by unstable population dynamics and poor somatic growth rates. One such assemblage is in Fish Lake, located in southern Utah, USA, in which introduced lake trout (Salvelinus namaycush, Walbaum) exhibit a bimodal growth pattern. A few lake trout in Fish Lake grow rapidly to large size typical of the species; whereas, most never grow beyond 600 mm total length. Objective: To inform competitive interactions in this evolutionarily novel fish assemblage that might cause the low recruitment to large body size in lake trout, we characterized trophic niche (from stable isotope analysis of C and N) of all fishes in the lake. Methods: We used a Bayesian mixing model to describe the trophic niche and infer diet of lake trout and their potential prey, and we used Bayesian ellipse analysis to identify potential areas of high competition within the food web. Large lake trout feed mostly on small lake trout and splake (Salvelinus namaycush, Walbaum x Salvelinus fontinalis, Mitchill) despite availability of abundant yellow perch. (Perca flavescens, Mitchill). Small lake trout and splake feed mostly on zooplankton and exhibit substantial overlap of their trophic niche implying competition for food. Yellow perch and Utah chub (Gila atraria, Girard; formerly an important food item for lake trout in Fish Lake) exhibit extreme overlap of their trophic niche implying strong competitive interactions. Results: Our data suggest that lack of recruitment to large body size in lake trout may result from a reduction in availability of Utah chub resulting from competitive interactions with yellow perch, and increased competition from introduced splake for available prey. Conclusion: Management actions that may help ameliorate the poor somatic growth rates of most lake trout include efforts to reduce perch populations or increase vulnerability of perch to predation by lake trout, and removal of splake as a competitor of small lake trout.
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Kurtul, Irmak, Ali Serhan Tarkan i J. Robert Britton. "Inter-tissue variability in the stable isotope values of European perch (Perca fluviatilis) and pumpkinseed (Lepomis gibbosus)". Knowledge & Management of Aquatic Ecosystems, nr 424 (2023): 22. http://dx.doi.org/10.1051/kmae/2023018.
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Ecological studies on native and invasive populations of European perch Perca fluviatilis and pumpkinseed Lepomis gibbosus are often based on stable isotope (SI) analysis based on dorsal muscle, where samples are usually taken from sacrificed fishes. However, other tissues, such as scale and fin tissue, can be used as non-lethal alternatives, where their SI values can be standardised to dorsal muscle values for comparative purposes. In both perch and pumpkinseed, there was a pattern of δ13C enrichment and δ15N depletion from muscle to fin and scale. As comparative studies must account for these inter-tissue differences prior to analyses, conversion equations for SI data from scale and fin tissue to standardised muscle values are provided.
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Dettmers, John M., John Janssen, Bernard Pientka, Richard S. Fulford i David J. Jude. "Evidence across multiple scales for offshore transport of yellow perch (Perca flavescens) larvae in Lake Michigan". Canadian Journal of Fisheries and Aquatic Sciences 62, nr 12 (1.12.2005): 2683–93. http://dx.doi.org/10.1139/f05-173.
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Most freshwater fishes have short pelagic early life stages. Lake Michigan presents an interesting scenario for yellow perch (Perca flavescens), a species with a long pelagic larval stage that may not be well adapted to lakes with an expansive pelagic environment and extensive offshore transport. We investigated the possibility that early life stages of yellow perch were transported well offshore from their nearshore spawning grounds and explored whether food resources were more or less favorable offshore. To determine the extent to which pelagic age-0 yellow perch moved offshore, we sampled at multiple scales ranging from local (<2 km) to across the lake (>120 km). Evidence of offshore movement by fish larvae occurred at each scale. Yellow perch larvae were quickly transported offshore from nearshore spawning sites and remained in the offshore pelagia to sizes of at least 30 mm. Zooplankton density was greater offshore than nearshore, suggesting that pelagic age-0 yellow perch find improved food resources offshore compared with their nearshore spawning sites. Currents operating at oceanographic scales likely influenced the offshore movement of pelagic age-0 yellow perch in Lake Michigan. These currents, coupled with prey availability for pelagic age-0 individuals, may influence the recruitment success of this species.
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Wedderburn, S. D., i T. C. Barnes. "Piscivory by alien redfin perch (Perca fluviatilis) begins earlier than anticipated in two contrasting habitats of Lake Alexandrina, South Australia". Australian Journal of Zoology 64, nr 1 (2016): 1. http://dx.doi.org/10.1071/zo15083.
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Redfin perch (Perca fluviatilis) introduced to the Southern Hemisphere has contributed to the decline or localised extirpations of native fishes, principally due to predation. It has been widely recorded in the Murray–Darling Basin, south-eastern Australia, since the 1920s but the ecological consequences are largely undetermined. The purpose of this study was to examine the diet of juvenile redfin perch in Lake Alexandrina to assess its potential impacts on native biota in two distinct habitats (channel and lake). We proposed that the broad dietary composition of juvenile redfin perch matches that of its natural range (small decapods and insects). Most juvenile redfin perch with prey items in their guts, however, had consumed native fish. There was variability in the diet of redfin perch between the channel and lake where gudgeons and gobies, respectively, were targeted. Unexpectedly, otolith ageing revealed that the redfin perch were larger and shifted to piscivory at a much younger age compared with populations in its native range. Among other ecological issues, the findings are pertinent to threatened small-bodied fish populations in the Murray–Darling Basin. More broadly, they suggest that a generalist feeding behaviour can lead to the early onset of piscivory in alien fish populations.
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Magee, Madeline R., Peter B. McIntyre i Chin H. Wu. "Modeling oxythermal stress for cool-water fishes in lakes using a cumulative dosage approach". Canadian Journal of Fisheries and Aquatic Sciences 75, nr 8 (sierpień 2018): 1303–12. http://dx.doi.org/10.1139/cjfas-2017-0260.
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Lake warming can negatively impact cool-water fishes through both temperature and oxygen stress. We modeled the joint dynamics of water column temperature and oxygen to quantify oxythermal habitat for yellow perch (Perca flavescens) in Fish Lake, Wisconsin, USA. To estimate annual oxythermal stress, we developed a novel metric (cumulative oxythermal stress dosage; COSD) that integrates both stress duration and stress magnitude. We find that COSD better predicts observed perch declines than the published TDO3 metric (temperature at depth where dissolved oxygen is 3 mg·L−1), which was developed for cold-water fish. Simulations show increases in COSD between 1911 and 2014, punctuated by a sharp rise since 1989. Extreme COSD years result from the intersection of high maximum daily dosage and prolonged duration exceeding the tolerance threshold. Temperature perturbation experiments to explore future climate scenarios reveal that COSD would increase greatly if the atmosphere warms by >3 °C. Applying the COSD metric broadly to temperate lakes could help direct management efforts toward the ecosystems most likely to serve as climate refugia for cold- and cool-water fishes in the future.
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Wisenden, Brian D., Josh Klitzke, Ryan Nelson, David Friedl i Peter C. Jacobson. "Predator-recognition training of hatchery-reared walleye (Stizostedion vitreum) and a field test of a training method using yellow perch (Perca flavescens)". Canadian Journal of Fisheries and Aquatic Sciences 61, nr 11 (1.11.2004): 2144–50. http://dx.doi.org/10.1139/f04-164.
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Fishes reared in captivity are predator-naïve and suffer large predation mortality when stocked into lakes with a full complement of predators. We tested the potential of predator training to enhance post-stocking survival of hatchery-reared walleye (Stizostedion vitreum). In the first part of the study, we found that walleye (i) use chemical cues for assessing predation risk, (ii) do not have innate recognition of the odor of northern pike (Esox lucius) as an indicator of predation, and (iii) associate predation risk with pike odor after a single simultaneous encounter with pike odor and chemical alarm cues from walleye skin. In the second part of the study, we attempted to mass-train yellow perch, Perca flavescens (as a surrogate for walleye), to fear pike odor. Perch response to pike odor was not changed by placing sponge blocks containing pike odor and perch alarm cues around the perimeter of a pond. On pre- and post-training assays, perch avoided traps scented with perch alarm cues, but did not avoid traps labeled with pike odor or water. We conclude that recognition training offers potential as a management tool for walleye, but significant logistic challenges must be solved before it can be implemented.
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Coble, Daniel W., Gordon B. Farabee i Richard O. Anderson. "Comparative Learning Ability of Selected Fishes". Canadian Journal of Fisheries and Aquatic Sciences 42, nr 4 (1.04.1985): 791–96. http://dx.doi.org/10.1139/f85-101.
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Fourteen species of freshwater fish were trained to execute a simple conditioned response in a shuttle box – to move in response to light to avoid an electrical shock. There was no relation between learning ability and phylogenetic position. Better learners included striped bass (Morone saxatilis), bigmouth buffalo (Ictiohus cyprinellus), common carp (Cyprinus carpio), and channel catfish (Ictalurus punctatus). Bluegill (Lepomis macrochirus) and northern pike (Esoxlucius) were poor learners. Yellow perch (Perca flavescens) and redbelly tilapia (Tilapia zilli) could not be trained. Some fish retained their learned behavior for months, although performance deteriorated with time. Older channel catfish learned better than juveniles, but there was no difference between juvenile and older largemouth bass (Micropterus salmoides). Temperature (18–28 °C) and feeding level (ranging from starvation for 25 d to ad libitum) did not affect learning of channel catfish, but the protozoan disease, ichthyophthiriasis, and perhaps our treatment of fish for the disease retarded it.
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Scharnweber, Kristin, Fernando Chaguaceda i Peter Eklöv. "Fatty acid accumulation in feeding types of a natural freshwater fish population". Oecologia 196, nr 1 (25.04.2021): 53–63. http://dx.doi.org/10.1007/s00442-021-04913-y.
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AbstractFatty acids are widely used to study trophic interactions in food web assemblages. Generally, it is assumed that there is a very small modification of fatty acids from one trophic step to another, making them suitable as trophic biomarkers. However, recent literature provides evidence that many fishes possess genes encoding enzymes with a role in bioconversion, thus the capability for bioconversion might be more widespread than previously assumed. Nonetheless, empirical evidence for biosynthesis occurring in natural populations remains scarce. In this study, we investigated different feeding types of perch (Perca fluviatilis) that are specialized on specific resources with different levels of highly unsaturated fatty acids (HUFAs), and analyzed the change between HUFA proportions in perch muscle tissue compared to their resources. Perch showed matching levels to their resources for EPA, but ARA and especially DHA were accumulated. Compound-specific stable isotope analyses helped us to identify the origin of HUFA carbon. Our results suggest that perch obtain a substantial amount of DHA via bioconversion when feeding on DHA-poor benthic resources. Thus, our data indicate the capability of bioconversion of HUFAs in a natural freshwater fish population.
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Schael, Denise M., Lars G. Rudstam i John R. Post. "Gape Limitation and Prey Selection in Larval Yellow Perch (Perca flavescens), Freshwater Drum (Aplodinotus grunniens), and Black Crappie (Pomoxis nigromaculatus)". Canadian Journal of Fisheries and Aquatic Sciences 48, nr 10 (1.10.1991): 1919–25. http://dx.doi.org/10.1139/f91-228.
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We compared prey selection of larval yellow perch (Perca flavescens), freshwater drum (Aplodinotus grunniens), and black crappie (Pomoxis nigromaculatus) in Lake Mendota, Wisconsin. All three species had a diet dominated by copepods and selected progressively larger prey as fish length increased. For a given fish length, freshwater drum selected larger prey and black crappie selected smaller prey than yellow perch. These differences in prey selectivity were partly explainable from differences in gape to length relationships. Freshwater drum did have the largest gape for a given length of the three species, but gape size for black crappie and yellow perch were similar. Gape size predicted 67% of the variability in mean prey size ingested by yellow perch but only 15% for freshwater drum and 8% for black crappie. Although gape size did predict the upper limit of ingestible prey sizes and explained some of the differences in prey selectivity among the three species, both the degree to which the different fishes can ingest prey close to their gape limit and the degree to which gape predicted mean size of ingested prey varied among the three fish species.
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Leuskyy, M., O. Buzevich, N. Rudyk-Leuska, G. Kotovska i D. Khrystenko. "Structural indices of the European perch (Perca fluviatilis Linnaeus, 1758) population in the Kremenchuk reservoir". Ribogospodarsʹka nauka Ukraïni., nr 3(61) (29.06.2022): 3–16. http://dx.doi.org/10.15407/fsu2022.03.003.
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Objective. Analysis of the structural parameters of the perch (Perca fluviatilis L.) population in the Kremenchuk Reservoir in the world of the development of the program of stocking large flat reservoirs of the Dnipro with juveniles of Far Eastern herbivorous fish, there was a need for methodical approaches to reduce the negative impact of small predators on the efficiency of planned stocking. Methodology. Primary materials related to the biology and fishing of perch were collected at the monitoring points of the Institute of Fisheries of the National Academy of Sciences. The basis of this article is the results of our own field research, which was carried out in the entire water area of the Kremenchuk Reservoir during 2016–2021. To determine the composition of catches in nets with different mesh sizes, the refined coefficient of annual commercial mortality was used. Results. The article establishes the general basic population indices of the perch (Perca fluviatilis L.) population in the Kremenchuk Reservoir. Acceptable indices of the perch population and the probability of its negative impact on the stocking of big-headed Chinese carps this year have been established. The scientific novelty of the work is due to the fact that effective stocking is currently possible only in the presence of scientifically based data, which can significantly affect the cost of planting material, and, as a result, the volume of work carried out. These basic principles are able to ensure the sustainable use of aquatic biological resources in natural reservoirs. Practical significance: the biological indices of the P. fluviatilis population presented in this work can be used to calculate the limits for perch commercial fishing in Kremenchuk Reservoir and to assess its negative impact on the stocked young fishes. Key words: perch, Kremenchuk Reservoir, length structure, catch per unit effort, commercial harvest.
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Shams, Foyez, Fiona Dyer, Ross Thompson, Richard P. Duncan, Jason D. Thiem, Zuzana Majtánová i Tariq Ezaz. "Karyotypes and Sex Chromosomes in Two Australian Native Freshwater Fishes, Golden Perch (Macquaria ambigua) and Murray Cod (Maccullochella peelii) (Percichthyidae)". International Journal of Molecular Sciences 20, nr 17 (30.08.2019): 4244. http://dx.doi.org/10.3390/ijms20174244.
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Karyotypic data from Australian native freshwater fishes are scarce, having been described from relatively few species. Golden perch (Macquaria ambigua) and Murray cod (Maccullochella peelii) are two large-bodied freshwater fish species native to Australia with significant indigenous, cultural, recreational and commercial value. The arid landscape over much of these fishes’ range, coupled with the boom and bust hydrology of their habitat, means that these species have potential to provide useful evolutionary insights, such as karyotypes and sex chromosome evolution in vertebrates. Here we applied standard and molecular cytogenetic techniques to characterise karyotypes for golden perch and Murray cod. Both species have a diploid chromosome number 2n = 48 and a male heterogametic sex chromosome system (XX/XY). While the karyotype of golden perch is composed exclusively of acrocentric chromosomes, the karyotype of Murray cod consists of two submetacentric and 46 subtelocentric/acrocentric chromosomes. We have identified variable accumulation of repetitive sequences (AAT)10 and (CGG)10 along with diverse methylation patterns, especially on the sex chromosomes in both species. Our study provides a baseline for future cytogenetic analyses of other Australian freshwater fishes, especially species from the family Percichthyidae, to better understand their genome and sex chromosome evolution.
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Turschak, Benjamin A., Sergiusz Czesny, Jason C. Doll, Brice K. Grunert, Tomas O. Höök, John Janssen i Harvey A. Bootsma. "Spatial variation in trophic structure of nearshore fishes in Lake Michigan as it relates to water clarity". Canadian Journal of Fisheries and Aquatic Sciences 76, nr 3 (marzec 2019): 364–77. http://dx.doi.org/10.1139/cjfas-2017-0390.
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Nearshore water clarity, as measured by remotely sensed Kd(490), and stable C and N isotopes of several nearshore fishes differed across the Lake Michigan basin. Values of δ13C of round goby (Neogobius melanstomus), yellow perch (Perca flavescens), and spottail shiner (Notropis hudsonis) were depleted in the southeast where water clarity was low relative to the southwest where water clarity was greater. Bayesian analyses were used to evaluate spatial variation in diet composition and quantify the relationship between water clarity and the proportional importance of pelagic energy in fish diets. Water clarity in nearshore areas is likely related to variable riverine inputs, resuspension, and upwelling processes. While these processes may not directly impact δ13C or δ15N of nearshore fishes, we hypothesize that water clarity differentially affects benthic and pelagic algal production. Lower water clarity in the benthos and subsequently lower benthic productivity may be related to regional diet differences and increased reliance on pelagic energy sources. Mobile fishes such as alewife (Alosa pseudoharengus) may not be in isotopic equilibrium with regional prey sources and depart from spatial patterns observed in other nearshore fishes.
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BEHRMANN-GODEL, JASMINCA. "Parasite identification, succession and infection pathways in perch fry (Perca fluviatilis): new insights through a combined morphological and genetic approach". Parasitology 140, nr 4 (2.01.2013): 509–20. http://dx.doi.org/10.1017/s0031182012001989.
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SUMMARYIdentification of parasite species is particularly challenging in larval and juvenile hosts, and this hampers the understanding of parasite acquisition in early life. The work described here employs a new combination of methods to identify parasite species and study parasite succession in fry of perch (Perca fluviatilis) from Lake Constance, Germany. Classical morphological diagnostics are combined with sequence comparisons between parasite life-stages collected from various hosts within the same ecosystem. In perch fry at different stages of development, 13 different parasite species were found. Incomplete morphological identifications of cestodes of the order Proteocephalidea, and trematodes of the family Diplostomatidae were complemented with sequences of mitochondrial DNA (cytochrome oxidase 1) and/or nuclear (28 s rDNA) genes. Sequences were compared to published data and used to link the parasites in perch to stages from molluscs, arthropods and more easily identifiable developmental stages from other fishes collected in Lake Constance, which both aided parasite identification and clarified transmission pathways. There were distinct changes in parasite community composition and abundance associated with perch fry age and habitat shifts. Some parasites became more abundant in older fish, whereas the composition of parasite communities was more strongly affected by the ontogenetic shifts from the pelagic to the littoral zone.
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Brown, Grant E., James C. Adrian, Jr., Todd Patton i Douglas P. Chivers. "Fathead minnows learn to recognize predator odour when exposed to concentrations of artificial alarm pheromone below their behavioural-response threshold". Canadian Journal of Zoology 79, nr 12 (1.12.2001): 2239–45. http://dx.doi.org/10.1139/z01-194.
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Hypoxanthine-3-N-oxide (H3NO) has been identified as the putative alarm pheromone of ostariophysan fishes. Previously we demonstrated a population-specific minimum behavioural-response threshold in fathead minnows (Pimephales promelas) to a H3NO concentration of approximately 0.4 nM. Minnows may, however, perceive low concentrations of H3NO as a predation threat, even though they do not exhibit an overt behavioural response. We conducted a series of laboratory trials to test the hypothesis that minnows can detect the alarm pheromone at concentrations below the minimum behavioural-response threshold. We exposed predator-naïve fathead minnows to H3NO at concentrations ranging from 0.4 to 0.05 nM paired with the odour of a novel predator (yellow perch, Perca flavescens) or distilled water paired with perch odour. We observed significant increases in antipredator behaviour (increased shoal cohesion, movement towards the substrate, a reduction in feeding, and an increase in the occurrence of dashing and freezing behaviour) in shoals of minnows exposed to a combined cue of 0.4 nM H3NO and perch odour (compared with a distilled-water control), but not by shoals exposed to lower concentrations of H3NO paired with perch odour or those exposed to distilled water paired with perch odour. When exposed to perch odour alone 4 days later, minnows initially conditioned to H3NO at concentrations of 0.40.1 nM exhibited significant increases in antipredator behaviour. These data demonstrate that minnows attend to the alarm pheromone at concentrations below the minimum behavioural-response threshold and are able to acquire the ability to recognize a novel predator even though they do not exhibit an overt behavioural response.
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Székely, Csaba, Réka Borzák i Kálmán Molnár. "Description of Henneguya jaczoi sp. n. (myxosporea, myxobolidae) from Perca fluviatilis (L.) (pisces, percidae) with some remarks on the systematics of Henneguya spp. of european fishes". Acta Veterinaria Hungarica 66, nr 3 (wrzesień 2018): 426–43. http://dx.doi.org/10.1556/004.2018.038.
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A new Henneguya species, H. jaczoi sp. n., is described from perch (Perca fluviatilis) from Lake Balaton, Hungary. This species infects the palatal region of the fish, forming large plasmodia in the thickened caudal part of the buccal cavity and at the dorsal ends of the cartilaginous gill arches. The species differs from the gill-dwelling Henneguya species of perch and pike (Esox lucius) both morphologically and in molecular aspects. The authors conclude that the type species H. psorospermica Thélohan is a specific parasite of pike, while the species forming plasmodia in the gills of perch corresponds to H. texta Cohn, which was hitherto regarded as a synonym of H. psorospermica. Besides the above-mentioned species, H. creplini was frequently found in pikeperch (Sander lucioperca) and Volga pikeperch (Sander volgensis), but no Henneguya infection has been recorded in ruffe (Gymnocephalus cernua), which is a common percid fish of the lake and is known to be the type host species for H. creplini.
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Vermeij, G. "How Victoria's fishes were knocked from their perch". Science 350, nr 6264 (26.11.2015): 1038. http://dx.doi.org/10.1126/science.aad7032.
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Schwalme, Karl, William C. Mackay i Dieter Lindner. "Suitability of Vertical Slot and Denil Fishways for Passing North-Temperate, Nonsalmonid Fish". Canadian Journal of Fisheries and Aquatic Sciences 42, nr 11 (1.11.1985): 1815–22. http://dx.doi.org/10.1139/f85-227.
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A vertical slot fishway and two Denil fishways (of 10 and 20% slope) built into a weir on the Lesser Slave River (55°18′N, 115°45′W) were studied from May 12 to June 25, 1984, to determine how effectively these designs pass north-temperate, nonsalmonid fishes. Thousands of spottail shiner (Notropis hudsonius), substantial numbers (> 100) of northern pike (Esox lucius), longnose sucker (Catostomus catostomus), white sucker (Catostomus commersoni), immature yellow perch (Perca flavescens), and lesser numbers of burbot (Lota lota), adult yellow perch, lake whitefish (Coregonus clupeaformis), and trout-perch (Percopsis omiscomaycus) ascended the fishways. Walleye (Stizostedion vitreum) and goldeye (Hiodon alosoides), although probably moving extensively through the river, did not use the fishways. Although high water levels allowed most fish to surmount the weir, of those that chose the fishway, pike strongly preferred to ascend the Denil fishways and the two sucker species preferred to ascend the vertical slot. Therefore, a combination of several different fishways may be required for the most efficient passage of a wide variety of species. Plasma glucose and lactate measurements on pike revealed that ascending the Denil fishways was only moderately stressful for these fish.
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Bjelić-Čabrilo, O., N. Novakov, M. Ćirković, D. Kostić, E. Popović, N. Aleksić i J. Lujić. "The first determination of Eustrongylides excisus Jägerskiöld, 1909 — larvae (Nematoda: Dioctophymatidae) in the pike-perch Sander lucioperca in Vojvodina (Serbia)". Helminthologia 50, nr 4 (1.12.2013): 291–94. http://dx.doi.org/10.2478/s11687-013-0143-1.
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AbstractTwenty-one specimens of pike-perch (Sander lucioperca) were caught in the Danube-Tisa-Danube Canal in the city area of Novi Sad for parasitological examination. The presence of nematodes in the muscles was revealed in three fish. The parasites were identified to belong to the species Eustrongylides excisus, for which the pike-perch is a paratenic host. This finding represents the first determination of the larvae in the pike-perch in Serbia. The pike-perch is infected by ingestion of benthos- or plankton-eating fishes, the second intermediate hosts harbouring the fourth-stage nematode larvae. E. excisus is pathogenic to humans, who may be infected by consuming raw or undercooked fish.
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Sandström, O., E. Neuman i P. Karås. "Effects of a Bleached Pulp Mill Effluent on Growth and Gonad Function in Baltic Coastal Fish". Water Science and Technology 20, nr 2 (1.02.1988): 107–18. http://dx.doi.org/10.2166/wst.1988.0051.
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Growth and reproductive capacity in perch (Percafluviatilia L.) and roach (Rutilusrutilus (L.)) were studied during 1983, 1984 and 1985 in a coastal area of the Bothnian Sea affected by bleached pulp mill effluents. Comparative investigations were made at a mill producing unbleached pulp. In perch exposed to bleachery effluents effects were observed on length increase rates, somatic condition factors and on gonad development. The fraction of fishes displaying inhibited gonadal recrudescence was high close to the mill, and the size of developing gonads was comparatively small. Growth was faster in exposed fishes, in young-of-the-year as well as in older fish. Effects on length growth could be distinguished as far back as in 1975. Energy storage, expressed as the condition factor, was highest in exposed fishes. The effect pattern was more diffuse in roach, but examples of reduced gonad growth were noted. In conclusion, these studies provided evidence for changes in the energy allocation system in fish exposed to a bleached pulp mill effluent.
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Lu, Yuehan, Stuart A. Ludsin, David L. Fanslow i Steven A. Pothoven. "Comparison of three microquantity techniques for measuring total lipids in fish". Canadian Journal of Fisheries and Aquatic Sciences 65, nr 10 (październik 2008): 2233–41. http://dx.doi.org/10.1139/f08-135.
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To measure lipids in juvenile and adult fishes, we refined three microquantity approaches (microgravimetric, microcolorimetric sulfophosphovanillan (SPV), and Iatroscan thin layer chromatography – flame ionization detection (TLC–FID)) that were originally developed to measure lipids in small aquatic invertebrates. We also evaluated their precision and comparability by quantifying the total lipid content of age-1+ walleye ( Sander vitreus ), yellow perch ( Perca flavescens ), and lake whitefish ( Coregonus clupeaformis ) collected in Lake Erie (US–Canada), Lake Michigan (USA), and Muskegon Lake (Michigan, USA). Our findings demonstrate that (i) microquantity approaches provide estimates of total lipids in juvenile and adult fishes similar to those of more traditional macroquantity approaches, (ii) the microcolorimetric SPV and microgravimetric approaches produce near identical estimates of total lipid content, and (iii) the Iatroscan TLC–FID approach underestimates total lipids relative to the other approaches for individuals with high lipid levels. Ultimately, our research makes available additional techniques for measuring total lipid content of fishes that are less expensive than traditional techniques, owing to a reduced need for large quantities of samples and solvents.
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Miller, Thomas J., Larry B. Crowder, James A. Rice i Fred P. Binkowski. "Body Size and the Ontogeny of the Functional Response in Fishes". Canadian Journal of Fisheries and Aquatic Sciences 49, nr 4 (1.04.1992): 805–12. http://dx.doi.org/10.1139/f92-091.
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The development of foraging abilities is crucial to the survival and subsequent recruitment of young fishes. We examined experimentally the notion that the foraging abilities of species are so different that useful generalizations across taxa are impossible. We investigated the ontogeny of feeding, reflected in their functional responses, in three Great Lakes' fishes, alewife (Alosa pseudoharengus), yellow perch (Perca flavescens), and bloater (Coregonus hoyi). No strong evidence of species-specific differences in the ontogeny of feeding ability was found. A single size-based relationship explained 52–88% of the variation in the parameters of the functional response equation. We conclude that interspecific differences in feeding abilities of larval fishes may have been overemphasized, and we suggest that interspecific differences should only be addressed within a size-based framework. This approach appears to provide an acceptable basis for first-order predictions of foraging abilities across taxa, for the identification of exceptional abilities which may lead to advances in the understanding of foraging ability, and for estimating foraging rates for important species for which data are now lacking.
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Thiel, R., T. Mehner, B. Kopcke i R. Kafemann. "Diet Niche Relationships among Early Life Stages of Fish in German Estuaries." Marine and Freshwater Research 47, nr 2 (1996): 123. http://dx.doi.org/10.1071/mf9960123.
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Diet composition, selectivity, food niche width and food niche overlap of early life stages of fishes were studied in the Barther Bodden system and in the Weser and Elbe estuaries during spring and summer from 1987 to 1991 and from 1993 to 1994. Larvae of perch (Perca fluviatilis) and roach (Rutilus rutilus) dominated in the Barther Bodden. Herring (Clupea harengus) and perch were the dominant species in the Barther Strom. Smelt (Osmerus eperlanus) was the most common species in the Elbe estuary. Sprat (Sprattus sprattus) was of most importance in the Weser estuary. The dominant prey of fish larvae were copepodids, nauplii and eggs of Eurytemora afinis. The highest food niche width was observed for nine-spined stickleback (Pungitius pungitius), ruffe (Gymnocephalus cernuus), three-spined stickleback (Gasterosteus aculeatus) and perch in the Barther Bodden. Negative selectivity indices indicated that populations of rotifers were scarcely influenced by predation by fish larvae. In contrast, E. affinis was preferred by early life stages of fish. Positive relationships were estimated between maximum prey lengths and predator lengths of different fish species. Key species with regard to niche overlap were nine-spined stickleback, roach, three-spined stickleback and perch in the Barther Bodden, perch and herring in the Barther Strom, herring and three-spined stickleback in the Elbe estuary, and sprat and common goby (Pomatoschisrus microps) in the Weser estuary. High geographical overlap between fish species occurred in the Elbe estuary and Barther Bodden, whereas high diet overlap was estimated for both the Weser estuary and Barther Strom.
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Goncharov, S. L., N. M. Soroka, I. Y. Pashkevich, A. I. Dubovyi i A. O. Bondar. "Infection of Predatory Fish with Larvae of Eustrongylides excisus (Nematoda, Dioctophymatidae) in the Delta of the Dnipro River and the Dnipro-Buh Estuary in Southern Ukraine". Vestnik Zoologii 52, nr 2 (1.04.2018): 137–44. http://dx.doi.org/10.2478/vzoo-2018-0015.
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Abstract The article describes occurrence and distribution of Eustrongylides trematodes in fish in the waters of the Dnipro-Buh estuary and the delta of Dnipro River in Mykolaiv and Kherson Region. Study was conducted in 2015–2016. This parasite was found in natural water reservoirs in Mykolaiv and Kherson region in following fish species: Sander lucioperca (Linnaeus, 1758), Perca fluviatilis (Linnaeus, 1758) and Esox lucius (Linnaeus, 1758). Ichtyopathological investigation of 346 fishes was conducted. Parasites were observed in abdominal cavity, muscle tissue, wall of gastro-intestinal tract, gonads and hepatopancreas. P. fluviatilis was the most affected species, prevalence of infection was 85.1 %. Less infected were S. lucioperca and E. lucius, with the prevalence of infection 58.1 % and 58.9 % respectively. Mean prevalence of infection of predatory fish in studied reservoirs was 70.5 %. The intensity of infection was the highest in perch (1–14 nematodes per fish). The lowest intensity of infection was found in pike-perch (1–9 nematodes per fish).
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Čepanko, Violeta, Raimondas Leopoldas Idzelis, Vytautas Kesminas i Rima Ladygienė. "RADIOLOGICAL INVESTIGATION OF ROACH AND PERCH FROM SOME LAKES IN LITHUANIA". JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 14, nr 4 (31.12.2006): 199–205. http://dx.doi.org/10.3846/16486897.2006.9636898.
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From the point of view of biological toxicity the most toxic radionuclides are man‐made 90Sr and 137Cs because the behavoir of both of them is similar to stable calcium and potassium in the body. Fish is the last part of the hydrosystem chain which accumulates pollutants. The aim of this study was to analyse the distribution of these two radionuclides in the muscle and other organs of perch and roach that differ by age and living conditions. Measurements were performed for 137Cs and 90Sr activity concentrations in fishes from the lakes of Drūkšiai, Lūkstas and Dusia. Radioecological investigation was carried out for different age groups of roach and perch analysing samples of muscle and spine bones (including the head of fish). Radioecological investigation of fishes from the lakes of Drūkšiai, Lūkstas and Dusia show that the activity concentrations of 137Cs and 90Sr are low. Anyway, the accumulated radioactivity by food chain reaches the human body. Nowadays a lot of investigations are related to the lakes in the vicinity of Ignalina NPP. The investigation shows that the activity concentrations of 137Cs and 90Sr in fishes from the Drūkšiai lake are the same as in fishes from other lakes in other locations of Lithuania.
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Matveev, A. N., V. P. Samusenok, A. L. Yuriev, A. I. Vokin, I. V. Samusenok i S. S. Alekseyev. "Biology of Fishes of Lake Frolikha (Northern Baikal Region, East Siberia)". Bulletin of Irkutsk State University. Series Biology. Ecology 32 (2020): 50–82. http://dx.doi.org/10.26516/2073-3372.2020.32.50.
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The fish fauna of Lake Frolikha comprises 12 species confirmed by our recent studies: roach Rutilus rutilus (L.), minnow Phoxinus phonixus (L.), stone loach Barbatula toni (Dyb.), spine loach Cobitis melanoleuca Nichols, pike Esox lucius L. lenok Brachymystax lenok (Pallas), Arctic charr Salvelinus alpinus (L.), Baikal black grayling Thymallus baicalensis (Dyb.), burbot Lota lota (L.), sand sculpin Leocottus kesslerii (Dyb.), stone sculpin Paracottus knerii (Dyb.) and perch Perca fluviatilis L. Biological peculiarities of these fishes are determined by unique geographical position and limnic characteristics of Lake Frolikha. Being a typical glacial lake it is located at rather low altitude a.s.l. and is adjacent to the unparalleled ecosystem of Lake Baikal. An underdeveloped shallow coastal zone with sparse aquatic vegetation, which is characteristic of glacial lakes, determines some biological traits of Lake Frolikha cyprinids. As compared with other mountain lakes of Baikal Rift Zone (BRZ), roach and minnow have lower rates of linear and weight growth as well as unusual population sex ratios. Male to female ratio in roach is 2:1 and in minnow it is 1:1 whereas in other lakes it reaches 1:4 and 1:10 respectively. The presence of native Baikal species in Lake Frolikha provided abundant food for piscivores: sand sculpins are the dominant food item of lenok, Arctic charr and perch. Lenok and perch demonstrate prominent linear and weight growth rate in the lake. In other lakes of BRZ with less abundant prey fish species Arctic charr typically diverge into several trophic forms, but in Lake Frolikha they established a monomorphic mostly piscivorous population. Charr from Lake Frolikha are relatively small and short-lived representatives of the large form of Transbaikalian charr. Their unique feature is river spawning, which is not observed in any other charr population within BRZ. Due to special protection regime of the territory, which minimizes catch losses, several fish species maintain natural unaffected structure of their populations evidenced by the abundance of old fish. The population of lenok is represented by 19 age groups, the population of roach – by 15 groups and that of burbot – by 12 groups. Alternatively, populations of small-sized prey species such as minnow and sand sculpin, which are heavily influenced by numerous predators include fewer age groups than in other mountain lakes of BRZ.
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Saddlier, Stephen, John D. Koehn i Michael P. Hammer. "Let’s not forget the small fishes – conservation of two threatened species of pygmy perch in south-eastern Australia". Marine and Freshwater Research 64, nr 9 (2013): 874. http://dx.doi.org/10.1071/mf12260.
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Small species without commercial value are often overlooked in conservation management. Pygmy perches are minature percichthyid fishes from temperate southern Australia of significant conservation concern, with five of the seven described species being threatened nationally. The present paper examines the plight of Yarra pygmy perch Nannoperca obscura, and variegated pygmy perch N. variegata, and discusses the progress of national (and State) recovery-plan actions. Threats and risks to these species are considerable; however, overall, few recovery actions have been completed and the status of many populations is unknown following the recent ‘millenium drought’. Habitat restoration, fish rescues, environmental water delivery and research into distribution, ecology and population dynamics are largely driven by individuals within singular local management authorities. Like many small fishes, they receive less attention than do larger ones and a cross-jurisdictional national recovery team is required to prioritise, coordinate and implement conservation efforts before the continued persistence of these species can be assured. These two small fishes are representative of many similar species and the lessons from the present case study may be applied elsewhere throughout the world.
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Raymond, Charles, Alfred Hugo i Monica Kung’aro. "Modeling Dynamics of Prey-Predator Fishery Model with Harvesting: A Bioeconomic Model". Journal of Applied Mathematics 2019 (2.06.2019): 1–13. http://dx.doi.org/10.1155/2019/2601648.
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A mathematical model is proposed and analysed to study the dynamics of two-prey one predator system of fishery model with Holling type II function response. The effect of harvesting was incorporated to both populations and thoroughly analysed. We study the ecological dynamics of the Nile perch, cichlid, and tilapia fishes as prey-predator system of lake Victoria fishery in Tanzania. In both cases, by nondimensionalization of the system, the equilibrium points are computed and conditions for local and global stability of the system are obtained. Condition for local stability was obtained by eigenvalue approach and Routh-Hurwitz Criterion. Moreover, the global stability of the coexistence equilibrium point is proved by defining appropriate Lyapunov function. Bioeconomic equilibrium is analysed and numerical simulations are also carried out to verify the analytical results. The numerical results indicate that the three species would coexist if cichlid and tilapia fishes will not be overharvested as these populations contribute to the growth rates of Nile perch population. The fishery control management should be exercised to avoid overharvesting of cichlid and tilapia fishes.
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Kotegov, B. G. "Variability of the countable features of head seismosensory system in different species of freshwater fishes and their dependence on hydrochemical factors". Marine Biological Journal 3, nr 3 (28.09.2018): 22–34. http://dx.doi.org/10.21072/mbj.2018.03.3.03.
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Countable morphological features in individuals of three mass species of fishes – roach, perch and crucian carp, living in small ponds of the Central-Eastern part of Udmurtia – were studied. The number of holes of seismosensory channels in some paired cover bones of the head skeleton of the caught fishes was counted and the sum of the values of these countable features (ΣSS) was calculated with averaging for the left and right sides. The total mineralization of water was also measured in the investigated reservoirs and the content of calcium and magnesium ions was estimated in the water. For all three fish species, one trend of interpopulation variability was revealed: with an increase of the concentration of Mg2+ in fresh water, the average value of ΣSS decreased in fish individuals from the studied populations. Statistically significant differences in mean values and frequency distributions of discrete variants of this seismosensory feature were observed for populations of roach, perch and crucian carp, living in water bodies with the greatest differences in the content of magnesium. In addition to full-scale research, laboratory experiments on aquarium cultivation of juvenile perch and roach in various hydrochemical conditions were carried out. Formed in fresh water with a high content of Mg2+, perch and roach juveniles had a smaller number of holes of seismosensory channels in some head bones in comparison with juveniles from the control groups and adult individuals of these fish species in reservoirs, where fertilized fish eggs for incubation were taken. Increased concentrations of Na+ did not have a similar effect on the formation of the studied signs. To explain the observed ontogenetic effects, we consider the possibility of direct influence of magnesium ions on the rate of larvae development of the freshwater fishes, as well as indirect influence on their morphogenesis of the competitive biochemical relations of this element with calcium.
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Hossain, MN, MGM Jamil, MM Mia, MN Uddin i MA Mansur. "Studies on the Proximate Composition, Quality and Heavy Metal Concentration of two Sun-Dried Marine Fish (Sun-Dried Silver Pomfret and Sun-Dried Perch) of Cox’s Bazar District of Bangladesh". Journal of Environmental Science and Natural Resources 10, nr 1 (28.11.2017): 25–32. http://dx.doi.org/10.3329/jesnr.v10i1.34690.
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This research was conducted on the proximate composition, quality aspect and heavy metal concentration of sun-dried Silver Pomfret (Stromateus cinereus) and sun-dried Perch (Lates calcarifer) which were collected from local market of Cox‟s Bazar town. These sun-dried marine fishes were collected from the stock after first drying procedure. Organoleptically most of these sun-dried fishes were in „excellent‟ grade some were in „Good‟ grade. Crude Protein, Lipid, Moisture, Ash, TVB-N and TMA-N content (%) of sun-dried Silver Pomfret (Stromateus cinereus) was 32.25±1.50, 7.75±0.20, 39.59±0.34, 15.75±0.39, 85.68±1.60 and 8.41±0.37 respectively. Whereas in sun-dried Perch (Lates calcarifer) the content (%) of Crude Protein, Lipid, Moisture, Ash, TVB-N and TMA-N was 40.31±2.13, 5.03±0.55, 26.74±0.47, 11.50±0.26, 46.97±1.00 and 8.21±0.12 respectively. Heavy metal concentration i.e. Cd, Cr, Pb, Cu and Zn concentration (ppm) in sun-dried Silver Pomfret (Stromateus cinereus) was 0.68, 5.85, 8.43, 1.15, 24.93 ppm. Whereas heavy metal concentration (ppm) in sun-dried Perch (Lates calcarifer) was Cd 0.65 ppm, Cr 5.6 ppm, Pb 6.28 ppm, Cu 1.04 ppm, Zn 23.8 ppm.J. Environ. Sci. & Natural Resources, 10(1): 25-32 2017
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Trifonova, Oxana P., Dmitry L. Maslov, Anton N. Mikhailov, Konstantin V. Zolotarev, Kirill V. Nakhod, Valeriya I. Nakhod, Nataliya F. Belyaeva, Marina V. Mikhailova, Petr G. Lokhov i Alexander I. Archakov. "Comparative Analysis of the Blood Plasma Metabolome of Negligible, Gradual and Rapidly Ageing Fishes". Fishes 3, nr 4 (4.12.2018): 46. http://dx.doi.org/10.3390/fishes3040046.
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There are a number of different animals that belong to long- and short-lived species and show a various rate of ageing, providing an ideal model to investigate mechanisms of longevity. In this work, a metabolome profiling of blood plasma from fishes with various ageing rates—negligible (Pike Esox Lucius and Sterlet Acipenser ruthenus), gradual (Zander Sander lucioperca and Perch Perca fluviatilis) and rapid (Chum Salmon Oncorhynchus keta and Pink Salmon Oncorhynchus gorbuscha)—was assessed by means of direct infusion to quadrupole time-of-flight mass spectrometry. Of the 2056 distinct m/z features detected by a mass spectrometry metabolic profiling of blood plasma samples, fifteen metabolites in the classes of dipeptides, fatty acids, glycerolipids, phosphoethanolamines and phosphatidylcholines were significantly associated with ageing rate, independent of species differences. This is the first study of the metabolome of fishes with various ageing rate, and this untargeted approach highlighted the metabolic conditions that may serve to assess the ageing process.
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Martseniuk, V. M., M. V. Prychepa i O. M. Marenkov. "Changes of Activity of Energy and Ion Exchange Enzymes and the Energy Substrates Content in Tissues of Perca fluviatilis and Rutilus rutilus under Toxic Water Pollution". Hydrobiological Journal 59, nr 3 (2023): 66–77. http://dx.doi.org/10.1615/hydrobj.v59.i3.50.
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The paper deals with impact of toxic pollution on activity of energy and ion exchange enzymes in roach and perch. Significant changes in content of energy substrates in liver, gills and muscles of perch and roach were established depending on season and toxic load. The glycogen content in liver of perch specimens from the polluted lake (Kyrilivske) was lower than in specimens from the control lake (Babyne). Also, lower activity of SDH in muscles and gills of roach has been established. It should be noted that roach was characterized by higher variability of the studied enzymes' activity. This indicates the species specificity of the metabolic reactions of the studied fishes to counteract toxic pollution.
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Koel, Todd M., i John J. Peterka. "Survival to hatching of fishes in sulfate-saline waters, Devils Lake, North Dakota". Canadian Journal of Fisheries and Aquatic Sciences 52, nr 3 (1.03.1995): 464–69. http://dx.doi.org/10.1139/f95-047.
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Laboratory-based bioassays were conducted to determine concentrations of sodium-sulfate type salinities that limit the hatching success of several fish species. Survival to hatching (SH) was significantly lower (P < 0.05) in sodium-sulfate type waters from Devils Lake, North Dakota, of ≥ 2400 mg/L total dissolved solids (TDS) than in fresh water of 200 mg/L. In waters of 200, 1150, 2400, 4250, and 6350 mg/L TDS, walleye (Stizostedion vitreum) SH was 41, 38, 7, 1, and 0%; northern pike (Esox lucius) SH was 92, 68, 33, 2, and 0%; yellow perch (Perca flavescens) SH was 88, 70, 73, 0, and 0%; white sucker (Catostomus commersoni) SH was 87, 95, 66, 0, and 0%; common carp (Cyprinus carpio) SH was 71, 69, 49, 63, and 25%.
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Dub, Joshua D., Rebecca A. Redman, David H. Wahl i Sergiusz J. Czesny. "Utilizing random forest analysis with otolith mass and total fish length to obtain rapid and objective estimates of fish age". Canadian Journal of Fisheries and Aquatic Sciences 70, nr 9 (wrzesień 2013): 1396–401. http://dx.doi.org/10.1139/cjfas-2013-0169.
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Age estimates from otolith morphometrics represent a rapid and objective alternative to traditional ageing techniques though use has been limited to marine and short-lived freshwater species. We utilized random forest analysis with otolith mass, total length, and several temporal and spatial predictor variables to assess variable importance and accuracy of age estimates for age-0 through age-11 yellow perch (Perca flavescens) in southwestern Lake Michigan. Accuracy of age predictions decreased with increasing age as 95% of juvenile (age-0 through age-2) ages were predicted correctly compared with 55% for adults (age-3 through age-11). Precision of age estimates within 1 year of reader-assigned age were high for both juvenile and adult yellow perch at 100% and 86%, respectively. Otolith mass was the most important predictor variable; however, substantial overlap existed among adult ages. Random forest analysis utilizing otolith mass, total length, and other pertinent predictor variables represents an applicable tool to reduce subjectivity and resource expenditure while providing accurate age estimates for juvenile and short-lived fishes.