{"title":"Additive effects of freshwater salinization on the predator-induced traits of larval amphibians","authors":"Bailey Tator, Mitchell Le Sage, Rick A. Relyea","doi":"10.1016/j.envpol.2025.126102","DOIUrl":null,"url":null,"abstract":"Freshwater salinization is occurring around the world and impacting a wide variety of freshwater species that have evolved under low-salt conditions. Salt pollution reduces the survival of many freshwater taxa, but we know less about the effects of salt on individual traits. Moreover, we know even less about how salt pollution may affect phenotypically plastic traits that have evolved in response to natural stressors. In this study, we examined wood frog tadpoles (<em>Rana sylvatica</em>), which are a model system for predator-induced plasticity, and determined how their growth, behavior, and morphology changed in the presence of chemical cues from dragonflies (<em>Anax junius</em>) under four concentrations of NaCl (16, 250, 500, and 1,000 mg Cl<sup>-</sup>/L). Early in the experiment, the tadpoles reduced their feeding activity in response to predator cues but did not respond to increasing salt concentrations. Tadpole mass increased with predator cues but decreased with increased salt concentrations. As expected, the predator cues induced relatively deeper tails and tail muscles, while inducing relatively shorter bodies and narrower mouths. However, we also discovered that salt induced relatively longer tails, longer bodies, and smaller eyes. Interestingly, the predator effects did not interact with salt effects for any of the traits. These results suggest that freshwater salinization has the potential to alter the traits of other freshwater species, but the effects may simply be additive. Future studies should examine salt-induced changes in a diversity of other freshwater species and investigate whether salt-induced changes in morphology have consequences to individual performance.","PeriodicalId":311,"journal":{"name":"Environmental Pollution","volume":"2 1","pages":""},"PeriodicalIF":7.6000,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Pollution","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1016/j.envpol.2025.126102","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Freshwater salinization is occurring around the world and impacting a wide variety of freshwater species that have evolved under low-salt conditions. Salt pollution reduces the survival of many freshwater taxa, but we know less about the effects of salt on individual traits. Moreover, we know even less about how salt pollution may affect phenotypically plastic traits that have evolved in response to natural stressors. In this study, we examined wood frog tadpoles (Rana sylvatica), which are a model system for predator-induced plasticity, and determined how their growth, behavior, and morphology changed in the presence of chemical cues from dragonflies (Anax junius) under four concentrations of NaCl (16, 250, 500, and 1,000 mg Cl-/L). Early in the experiment, the tadpoles reduced their feeding activity in response to predator cues but did not respond to increasing salt concentrations. Tadpole mass increased with predator cues but decreased with increased salt concentrations. As expected, the predator cues induced relatively deeper tails and tail muscles, while inducing relatively shorter bodies and narrower mouths. However, we also discovered that salt induced relatively longer tails, longer bodies, and smaller eyes. Interestingly, the predator effects did not interact with salt effects for any of the traits. These results suggest that freshwater salinization has the potential to alter the traits of other freshwater species, but the effects may simply be additive. Future studies should examine salt-induced changes in a diversity of other freshwater species and investigate whether salt-induced changes in morphology have consequences to individual performance.
期刊介绍:
Environmental Pollution is an international peer-reviewed journal that publishes high-quality research papers and review articles covering all aspects of environmental pollution and its impacts on ecosystems and human health.
Subject areas include, but are not limited to:
• Sources and occurrences of pollutants that are clearly defined and measured in environmental compartments, food and food-related items, and human bodies;
• Interlinks between contaminant exposure and biological, ecological, and human health effects, including those of climate change;
• Contaminants of emerging concerns (including but not limited to antibiotic resistant microorganisms or genes, microplastics/nanoplastics, electronic wastes, light, and noise) and/or their biological, ecological, or human health effects;
• Laboratory and field studies on the remediation/mitigation of environmental pollution via new techniques and with clear links to biological, ecological, or human health effects;
• Modeling of pollution processes, patterns, or trends that is of clear environmental and/or human health interest;
• New techniques that measure and examine environmental occurrences, transport, behavior, and effects of pollutants within the environment or the laboratory, provided that they can be clearly used to address problems within regional or global environmental compartments.