Ecology of Freshwater Fish最新文献

{"title":"Temporal Patterns and Drivers of Freshwater Fish Beta-Diversity of Gravel Pit Lakes","authors":"Flavien Garcia,&nbsp;Julien Cucherousset,&nbsp;Julian D. Olden","doi":"10.1111/eff.70024","DOIUrl":"https://doi.org/10.1111/eff.70024","url":null,"abstract":"<p>Freshwater ecosystems are in the midst of a biodiversity crisis marked by non-random and often dramatic shifts in fish community composition. Yet, the patterns and underlying ecological drivers of these community dynamics within gravel pit lakes—widespread artificial lakes with significant socioeconomic and ecological value—remain understudied. This study examines patterns and drivers of beta-diversity of fish communities across 16 gravel pit lakes in southwestern France over 10 years. Our results unveiled strong shifts in fish community composition, with lake maturity (older and more productive) emerging as the main driver. Immature lakes experienced substantial species turnover over one decade, harbouring more unique fish communities, whereas mature lakes showed little change, contributing less to overall beta-diversity. Highly invaded lakes displayed higher levels of species nestedness than species turnover compared with uninvaded lakes. The contributions of native and non-native species to beta-diversity remained relatively constant on average over the study period, although with some notable exceptions. Non-native species such as common carp (<i>Cyprinus carpio</i>) and Wels catfish (<i>Silurus glanis</i>) had increasing contributions to beta-diversity, whereas native European perch (<i>Perca fluviatilis</i>) and roach (<i>Rutilus rutilus</i>) were increasingly more common (i.e., widespread) despite declining biomass when present. A number of abiotic and biotic factors likely contributed to the diversity patterns observed. Eutrophication is associated with increasing turbidity and hypoxia/anoxia, promoting the dominance of more tolerant, largely non-native, fish species. The higher proportion of species nestedness in invaded communities may stem from reduced invasibility or local extinctions over time. Finally, European perch, a pioneer species, exhibited increasing homogenisation of its biomass across lakes over the 10-year period, resulting in similar small populations distributed throughout the study area. These findings highlight temporal changes in fish community composition within gravel pit lakes, revealing the complex interplay between lake maturity and non-native species dynamics as major drivers.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70024","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144929666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parasites Are Paramount: Vertical Trophic Positions of Parasitic Catfishes in a Tropical River Food Web","authors":"Carmen G. Montaña,&nbsp;Chase Nimee,&nbsp;Sophie Scott,&nbsp;Megan Beeksma,&nbsp;Kendall Hasting,&nbsp;Takiya Jackson,&nbsp;Leslie Kelso-Winemiller,&nbsp;Kirk O. Winemiller","doi":"10.1111/eff.70025","DOIUrl":"https://doi.org/10.1111/eff.70025","url":null,"abstract":"<p>The Neotropical catfish family Trichomycteridae contains parasitic fishes that include scale and mucus feeders (subfamily Stegophilinae) and blood feeders (i.e., ‘candirus’, subfamily Vandelliinae). The influence of parasitic catfishes on food web dynamics is unknown. Most ecological information on the feeding ecology of freshwater parasite catfishes has been based on visual observation of diets via stomach contents analysis, a method that does not provide information about the origin of ingested blood or mucus (interspecific interactions) or vertical trophic position of these parasites. We used stable isotope analysis of carbon (d¹³C) and nitrogen (d¹⁵N) to explore the role of parasitic catfishes in a river food web in Guyana, South America. We obtained tissue samples from over 100 fish species, including three genera of trichomycterid parasitic catfishes. Parasitic catfishes were estimated to have the highest trophic positions in the food web, which, given their small size (~5 cm total length), contributed to a weak relationship between trophic position and fish body size for the fish community. <i>Ochmacanthus</i>, a mucus-feeder, had higher d¹⁵N and estimated trophic position than the two blood feeders, <i>Paracanthopoma</i> and <i>Vandellia</i>. Results from stable isotope analysis indicate that parasitic catfishes should be considered among the top consumers in this hyperdiverse fish community.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70025","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144905416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Competition or Habitat: Co-Occurrence of Endemic and Cosmopolitan Black Bass Species in a Changing Landscape","authors":"Caroline Cooper,&nbsp;Kyle Barrett,&nbsp;Tanya L. Darden,&nbsp;Daniel J. Farrae,&nbsp;Kevin Kubach,&nbsp;Mark C. Scott,&nbsp;Brandon K. Peoples","doi":"10.1111/eff.70023","DOIUrl":"https://doi.org/10.1111/eff.70023","url":null,"abstract":"<p>The black basses of the southeastern United States are an excellent study group for investigating the relative roles of habitat and biotic interactions for determining species co-occurrence. This group is comprised of generalist species such as Largemouth Bass <i>Micropterus nigricans</i>, as well as specialist species such as those within the <i>M. coosae</i> complex. Bartram's Bass <i>M.</i> sp. cf. <i>coosae</i> is a provisional species of particular concern endemic to the upper Savannah River basin of Georgia, South Carolina and North Carolina, USA. Bartram's Bass and Largemouth Bass may occur in the same rivers, but do not necessarily co-occur in the same micro- or mesohabitats. Recent surveys in numerous Savannah River tributaries where Bartram's Bass was previously known to have existed have either detected only Largemouth Bass or no black basses at all. The apparent loss of endemic Bartram's Bass and frequent replacement with cosmopolitan Largemouth Bass is concerning from a conservation perspective because it could indicate either (a) ongoing biotic homogenisation via habitat shifts, (b) habitat-mediated asymmetric interspecific interactions resulting incompetitive exclusion, or (c) some combination of these processes. In this study, we assessed differences in landscape-level factors and proximity to reservoirs on the occurrence and co-occurrence of these species using a multispecies occupancy model developed for two or more potentially interacting species. This approach can be used to untangle the relative roles that biotic interactions or habitat covariates have on species distributions. The most compelling model evidence suggested that Bartram's Bass and Largemouth Bass were associated with land cover effects on instream habitat and provided less evidence that co-occurrence was driven by interspecific interactions. Human land use change and impoundment of free-flowing rivers have created new opportunities for Largemouth Bass to access upstream lotic habitats and are associated with the loss of lotic habitats and restricted the distribution of Bartram's Bass.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70023","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144767889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whole Lake Behaviour of Sea-Run Brown Trout During Pre-Spawning Months","authors":"Robert J. Lennox,&nbsp;Lotte Svengård Dahlmo,&nbsp;Cecilie Iden Nilsen,&nbsp;Henrik Baktoft,&nbsp;Knut Wiik Vollset","doi":"10.1111/eff.70021","DOIUrl":"https://doi.org/10.1111/eff.70021","url":null,"abstract":"<p>Sea-run brown trout use lake habitat extensively when it is available both before and after spawning. However, the ways in which brown trout actually use lakes remain poorly resolved. In Norway, some of these lakes are used as reservoirs for the effluent of high-head power stations that tunnel mountain water through turbines, discharging the water into the lakes that support migratory species like trout. In this study, we calculated the positions of tagged trout in Lake Vassbygdivatnet, western Norway from July–November 2021 using acoustic telemetry and YAPS software in the R programming environment. We fitted kernel density estimators to the positioning data to estimate core areas where the trout were found within the lake and identified hotspots close to shore near locations in the lake where cascades discharged from the surrounding mountains. However, a resource selection function type analysis identified no affinity of the trout for the area immediately adjacent to the high-head power station outlet. Finally, a hidden Markov model determined that the nearshore lake margin was mostly used by trout for more passive states (low directionality, short steps), whereas the middle of the lake was more frequently used for active states (high directionality, long steps). The findings demonstrate for the first time that mountain cascades discharging into lakes provide habitat that attracts trout and that there is no clear attraction towards the power station outlet during the pre-spawn period. Risk of entrainment in the power station tunnel therefore does not seem to be a major risk factor for migrating trout. However, fisheries managers may wish to use these findings when regulating fishing activities in lakes like Vassbygdivatnet where trout stage in preparation for spawning.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vulnerability of Early Life-Stage Lake Whitefish and Cisco to Invasive Nearshore Predators","authors":"Kelly A. Hoyer,&nbsp;Tracy L. Galarowicz,&nbsp;Jory L. Jonas,&nbsp;J. Ellen Marsden,&nbsp;Kevin L. Pangle,&nbsp;Jason B. Smith,&nbsp;A. Scott McNaught","doi":"10.1111/eff.70022","DOIUrl":"https://doi.org/10.1111/eff.70022","url":null,"abstract":"<div>\u0000 \u0000 <p>In recent years (post 2010), the recruitment of populations of cisco (<i>Coregonus artedi</i>) in the Great Lakes and surrounding inland lakes has generally increased. Conversely, recruitment of lake whitefish (<i>C. clupeaformis</i>) populations is declining, in some cases at alarming rates. Differential survival of the two species is likely set during early life stages and may be partially explained by differences in avoidance behaviours, particularly in the presence of more recently introduced nearshore predators, like round goby (<i>Neogobius melanostomus</i>) and rainbow smelt (<i>Osmerus mordax</i>). We evaluated the predation success of three sizes of round goby (small, 59–59 mm total length (TL)), medium, 82–92 mm TL and large, 111–132 mm TL) and one size of rainbow smelt (130–144 mm TL) consuming lake whitefish and cisco at various early life stages—larval, early juvenile and juvenile. Controlled predation trials were conducted and recorded for 30 min. to examine foraging behaviours of potential predators and avoidance patterns of the two coregonine species at the three early life stages. Round goby capture success and attacks per pursuit were primarily related to coregonine life stage (i.e., size), but medium and large round goby had higher success with captures and/or predation efficiency on early juvenile and juvenile lake whitefish than cisco. The number of attacks per pursuit by rainbow smelt was higher on juvenile lake whitefish than cisco, which did not lead to different capture rates. Juvenile cisco exhibited stronger anti-predator response (i.e., tighter group cohesion) than juvenile lake whitefish, which could contribute to lower predation success and/or lower efficiency by introduced predators. Our results suggest that round goby (&gt; 65 mm TL) may have an impact on survival of early juvenile and juvenile lake whitefish, and rainbow smelt may have a larger impact on juvenile lake whitefish than cisco during times of spatial overlap in late spring. Predation by these two invasive fish species in the Great Lakes has the potential to at least partially explain recruitment differences between lake whitefish and cisco.</p>\u0000 </div>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144688220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Movement Pattern and Habitat Use of the Endangered Brook Barbel (Barbus caninus) in a Mediterranean Stream","authors":"Alfredo Schiavon,&nbsp;Claudio Comoglio,&nbsp;Alessandro Candiotto,&nbsp;Michele Spairani,&nbsp;Franz Hölker,&nbsp;Johan Watz,&nbsp;Daniel Nyqvist","doi":"10.1111/eff.70017","DOIUrl":"https://doi.org/10.1111/eff.70017","url":null,"abstract":"<p>Understanding the ecology and behaviour of freshwater fish species is essential for effective management and conservation. Within the genus <i>Barbus</i>, small-sized mountain species remain understudied despite conservation concerns. In this study, we investigated the movement patterns, habitat use and flow preferences of the endangered species <i>Barbus caninus</i> in a Mediterranean mountain stream in northern Italy using passive integrated transponder telemetry. Over a 15-month period, 164 tagged fish were tracked between 2 and 30 times. Most individuals exhibited small home ranges, with a median linear range of 33.7 m, although a few fish moved over hundreds of metres. Fish size did not influence movement patterns. Movements were seasonally variable, with a significantly larger linear range observed during spring compared to other seasons. The barbel showed a weak preference for fast-flowing mesohabitats, and this preference was pronounced during winter. Despite this, <i>B. caninus</i> predominantly utilised low-velocity confined zones within hydromorphological units, potentially indicating energetically efficient microhabitat use. These findings shed light on the habitat requirements and movement patterns of an endangered species that inhabits small mountain streams and is subject to numerous anthropogenic threats.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144635322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Juvenile Convict Cichlids Prefer Shoals Over Potential Shelters","authors":"Karen O'Brien,&nbsp;Natalie A. van Breukelen","doi":"10.1111/eff.70019","DOIUrl":"https://doi.org/10.1111/eff.70019","url":null,"abstract":"<div>\u0000 \u0000 <p>Successful strategies of predator deterrence or avoidance are necessary for juvenile organisms to survive to adulthood. Individuals should balance the benefits and risks of any strategy they choose. One strategy used by many fish species is shoaling by forming a loose grouping of conspecifics. This may deter predators through dilution or confusion, though it also increases competition between shoal mates. Another strategy is hiding to avoid predation, though hiding spots are only effective to avoid visual predators and may also be used by predators. Juvenile convict cichlids (<i>Amatitlania nigrofasciata</i>) were given a choice between a shoal of juvenile conspecifics and a potential shelter (plants/rocks), in the presence and absence of a predator (<i>Parachromis dovii</i>). We predicted that the fish would prefer the shoal when the predator was present and would prefer the potential shelter when the predator was absent because while shoaling is a predator deterrent it increases competition for resources. We found that the juvenile convict cichlids preferred to spend more time with a shoal than the potential shelter and did not prefer the potential shelter alone, and this preference did not change with predator presence. This suggests that not only did they prefer the shoal, but that they may have been avoiding the potential shelters, indicating a flexible strategy.</p>\u0000 </div>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144558199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal and Ontogenetic Changes in Feeding Ecology of a Characid From Karst Dolines of the Neotropics","authors":"Amanda Menegante Caldatto,&nbsp;Rosa Maria Dias,&nbsp;Fernando César Paiva Dagosta,&nbsp;Anderson Ferreira","doi":"10.1111/eff.70018","DOIUrl":"https://doi.org/10.1111/eff.70018","url":null,"abstract":"<p>Environmental and biological factors strongly shape fish diets, yet little is known about such influences in flooded Karst Dolines of the Neotropical region. This study examined the diet of <i>Deuterodon luetkenii</i> and assessed its temporal and ontogenetic variation in Lagoa Misteriosa, a karstic lagoon. Fish were sampled bimonthly over 1 year and categorised into two hydrological periods: with algal blooms (WAB) and without algal blooms (AAB). A total of 540 stomachs from four body size classes were analysed, identifying 33 food items. Diet composition varied significantly between periods and among size classes. Filamentous algae and macrophytes were more consumed during the AAB period, while aquatic invertebrates predominated during the WAB period. Niche breadth remained consistent across periods but differed among size classes, indicating ontogenetic dietary shifts. Our findings underscore the ecological role of autochthonous resources and macrophytes in shaping feeding strategies and habitat use in karst ecosystems. Understanding these dynamics is crucial for conservation efforts and for anticipating the potential impacts of environmental changes on trophic interactions within karst environments.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 4","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144558198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Summer and Autumn Movement of Endemic Bartram's Bass, Invasive Alabama Bass and Hybrid Congeners in an Upper Savannah River Tributary","authors":"Tyler R. Zumwalt,&nbsp;Troy M. Farmer,&nbsp;Mark C. Scott,&nbsp;Daniel J. Farrae,&nbsp;Tanya L. Darden,&nbsp;Henry J. Hershey,&nbsp;Brandon K. Peoples","doi":"10.1111/eff.70014","DOIUrl":"https://doi.org/10.1111/eff.70014","url":null,"abstract":"<p>Bartram's Bass <i>Micropterus</i> sp. <i>cf. coosae</i> is endemic to the Upper Savannah River Basin of the southeastern United States, and is threatened by hybridization with invasive Alabama Bass <i>M. henshalli</i>. Quantifying movement of these species and their hybrids will improve understanding of how nonnative alleles spread among riverine fish populations. We quantified summer/autumn movement of Bartram's Bass, Alabama Bass and hybrid bass in Eastatoee Creek—a tributary experiencing ongoing invasion from Keowee Reservoir. To do this, we first quantified factors associated with the longitudinal distribution and weekly movement rates of each species, then estimated probabilities of species transitioning among key habitats at the river-reservoir interface. We tagged 291 fish with passive integrated transponder tags, sampling the entire stream length of Eastatoee Creek four times in both 2021 and 2022. We radio-tagged an additional 52 fish and tracked them from early May through mid-October each year. We used mixed effect models and a Bayesian multistate model to quantify movement, river position, movement probability and the effects of abiotic factors thereon. Alabama Bass and hybrid bass moved more than Bartram's Bass and remained in the lower reaches of Eastatoee Creek, apparently restricted by a reach of high-gradient habitat that functioned as a natural barrier. Alabama Bass made greater upstream movements during cooler spring temperatures when higher reservoir levels inundated the creek mouth. Bartram's Bass were distributed throughout Eastatoee Creek, making shorter weekly upstream movements associated with increasing temperature in late spring. Movement of hybrid bass from lower portions of tributaries is likely a primary source of nonnative allele spread in this system.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144472822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Body Size and Thermal Sensitivity of a Facultative Air-Breathing Fish Amidst Environmental Change","authors":"Erin K. Francispillai,&nbsp;Lauren J. Chapman","doi":"10.1111/eff.70015","DOIUrl":"https://doi.org/10.1111/eff.70015","url":null,"abstract":"<p>Many freshwater fish populations are increasingly required to respond to warming waters and low dissolved oxygen concentrations as a result of land-use change and climate change. In addition, the average size of fish in harvested populations can be drastically reduced due to heavy fishing pressure. These factors may be more pronounced in African countries due to current high rates of forest conversion and a greater dependency on local fish catch. To investigate the relationship between fish body size and heat tolerance, we compared the upper thermal tolerance limits (estimated as the Critical Thermal Maximum, CT_max) of the smooth-head catfish (<i>Clarias liocephalus</i>), a facultative air-breathing fish, sampled from Lwamunda Swamp, Uganda. We included additional CT_max trials under low dissolved oxygen concentrations (0.20–0.50 mg/L) to test for potential interactive effects between body size and hypoxia on upper thermal tolerance. Body size did not affect <i>C. liocephalus</i> upper thermal limits, as small and large individuals had similar CT_max values. CT_max values decreased under hypoxic conditions but were similar across a range of body sizes. The agitation temperature (temperature during the CT_max trials when individuals appeared to become agitated, likely avoidance behaviour) was positively related to body size. This suggests that smaller individuals may be more thermally sensitive than larger fish in terms of their behavioural response to acute temperature increase.</p>","PeriodicalId":11422,"journal":{"name":"Ecology of Freshwater Fish","volume":"34 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/eff.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144339626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}