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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Predicting habitat functionality using habitat network models in urban planning</title>
      <link>https://trid.trb.org/View/2567198</link>
      <description><![CDATA[Recently, the European Union adopted a Nature restoration law that aims to stop the ongoing decline of biodiversity and even bring back nature to cities. This is challenging as urbanization is an ongoing process that thrives for more land and densification. In this paper the authors describe a new Open-Source GIS-tool that automates habitat network analyses and simultaneously generates several maps that can be used for assessments, targeting species survival in urban environments. One result of particular interest is the habitat functionality map that combines values of habitat quality and connectivity. The authors tested the tool’s ability to predict habitat functionality using amphibian occurrence data observed from the city of Gothenburg in Sweden. The authors' evaluation shows that habitat functionality was generally a good predictor of amphibian distribution. However, the predictability was sensitive to the cartographic representativity of the input biotope map used. Also, predictions of habitat functionality improved when estimating dispersal probabilities using the Cost-distance algorithm, compared to when using Euclidean distance from reproductive habitats. This finding supports the need to use connectivity models that are responsive to variation and changes in roads, traffic volumes and buildings when performing effect analyses on biodiversity in cities. Finally, the authors demonstrate how the tool can be used to easily identify areas where restoration measures can effectively increase habitat functionality for target species. This can help planners to find efficient solutions for increasing biodiversity within urban areas.]]></description>
      <pubDate>Fri, 22 Aug 2025 17:24:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2567198</guid>
    </item>
    <item>
      <title>Improved Non-Invasive Detection of Cryptobranchus Allegeniensis using Multiplexed Total Nucleic Acid eDNA/eRNA Comparisons</title>
      <link>https://trid.trb.org/View/2561922</link>
      <description><![CDATA[The Eastern Hellbender (Cryptobranchus alleganiensis) is a scarce and reclusive aquatic salamander that resides in swiftly flowing streams within isolated regions of Appalachia. Hellbender populations have been decreasing for decades and Hurricane Helene's recent devastation of Western North Carolina further disrupted population strongholds with reports of the animals displaced and killed due to flash floods in the Hurricane's wake. The recent U.S. Fish and Wildlife request for federal protection under the Endangered Species Act has emphasized the importance of ongoing conservation efforts for the animal, including monitoring and preserving the existing population. Traditional field surveys (TFS) make up the bulk of Hellbender detection efforts although multiple, non-invasive environmental DNA (eDNA) assays have been developed in recent years. Adoption of any eDNA method requires meticulous testing and verification, as some published primer sets for Hellbender have been shown to produce off-target amplification.

The goal of this research is to increase the sensitivity and accuracy of eDNA detection methods for the Eastern Hellbender, and to provide an additional molecular target for Ohio stream conservation assessments. This work will consist of developing an RNA molecular marker to examine Eastern Hellbender in conjunction with a DNA marker for Spotted Darter populations through environmental nucleic acids-thus, widening the scope of past Hellbender eDNA assays and providing additional information and confidence in results through eRNA. Both primer sets will be validated by rigorous testing on diverse nucleic acid extractions as performed previously                ]]></description>
      <pubDate>Thu, 05 Jun 2025 15:01:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2561922</guid>
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    <item>
      <title>Tell me where you go, and I’ll tell you where you die: landscape connectivity as a tool to predict amphibian roadkill risk</title>
      <link>https://trid.trb.org/View/2534862</link>
      <description><![CDATA[Human overpopulation, development, and consequent activities such as land conversion and linear infrastructure expansion, are currently some of the main threats to biodiversity. Amphibians are especially affected because they depend on both aquatic and terrestrial habitats to complete their life cycles, which can be negatively impacted by roads, due to reduced landscape connectivity. Understanding animal movement across the landscape may improve the prioritisation of sites to implementing mitigation measures. The authors assessed landscape connectivity using circuit theory, for two amphibian species (the Iberian spadefoot toad and the Iberian ribbed newt) on a Mediterranean landscape in Southern Portugal. The authors addressed the following question: Can landscape connectivity predict amphibian roadkill risk? The authors' connectivity models assigned higher current movement corridors to heterogeneous habitats composed of sparse forests combined with low-management agricultural areas and good networks of higher-density water bodies. The authors found a positive correlation between high-connectivity road segments and roadkill for both species, proving that landscape connectivity can be a valuable tool to predict locations with higher roadkill probability. The authors acknowledge that maintaining a heterogeneous landscape, with a higher density of short-distance water bodies that connect highly suitable habitats is important for amphibians. The identification of corridors with increased amphibian movement probability provides useful insights for road agencies to implement amphibian-oriented roadkill mitigation measures.]]></description>
      <pubDate>Tue, 27 May 2025 09:33:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2534862</guid>
    </item>
    <item>
      <title>Roadway Crossings for Sensitive Amphibians and Reptiles: Phase II</title>
      <link>https://trid.trb.org/View/2487568</link>
      <description><![CDATA[Many migratory amphibians make annual population-level migrations among breeding wetlands and over-wintering and/or summer foraging upland terrestrial habitats. To reduce the negative impacts from road mortality on these vulnerable populations, it has been standard practice to build safe crossings in the form of small passages connected by barrier fencing as mitigation. The permeability of crossing structures is dependent upon the proportion of migrating animals that even reach the passages. In Phase 1 of this project, California tiger salamanders (Ambystoma californiense; CTS) were shown to move an average of approximately 40m along a barrier fence before giving up (90% tolerance interval of 12.5m). CTS that came in contact with fencing and initially moved the ‘wrong’ way (away from a passage) had a very low probability of reaching the passage system. In another study, turnarounds, often placed at fence ends, were shown to be effective in changing the trajectory of amphibians and reptiles. In this Phase 2 study, the authors tested if multiple turnarounds along the length of barrier fencing would increase the probability reaching the passage system. At the study site in Stanford, CA, the authors installed turnarounds every 25m, with an additional turnaround 12.5m from the passage system. Individual CTS movements were monitored using active-trigger cameras, documenting speed, direction, use of turnarounds, and success at reaching the passage system for 3 years prior and 2 years after the multiple turnarounds were in place. The results showed that an average of 36% of CTS initially turned in the ‘wrong’ direction. Prior to installation of multiple turnarounds, 5% of CTS that initially turned in the ‘wrong’ direction made it to the passage system. After installation of the turnarounds, 96% of CTS that initially turned in the ‘wrong’ direction interacted with one or more turnarounds and their probability of reaching the passage system increased to that of CTS that initially moved in the ‘right’ direction (mean 66% success rate); with probabilities increasing in relation to initial distance from passage. To the authors' best knowledge, this is the first study of multiple turnarounds and their impacts on passage system permeability. In addition to increasing the number and quality of passages along migratory pathways, the authors believe this is promising and cost-effective method to increase overall permeability of passage-barrier systems to migrating amphibians.]]></description>
      <pubDate>Tue, 14 Jan 2025 13:43:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2487568</guid>
    </item>
    <item>
      <title>Amphibian roadkill patterns in an Asian tropical rainforest</title>
      <link>https://trid.trb.org/View/2427933</link>
      <description><![CDATA[Wildlife roadkills have emerged as one of the most adverse impacts of road networks on biodiversity. Knowledge regarding amphibian roadkill patterns in Asian tropical rainforests is limited. Herein, the authors present the first assessment of roadkill patterns of amphibians in the Hainan tropical rainforest of southern China, based on extensive field surveys covering 58 road transects in 2021 and 2022. The authors investigated the effects of species characteristics, seasons, and environmental factors on amphibian roadkill patterns. The authors recorded 503 amphibian carcasses and identified 13 amphibian species. Abundant species are more likely to be killed. There were no significant differences in the roadkill observations between the dry and wet seasons. The number of roadkill observations correlated positively with the percentage of area with buildings. The authors' findings provide new insights into the ecological effects of roads and transportation in Asian tropical rainforests, which will help design and implement conservation actions. The authors suggest prioritizing permanent mitigation measures to reduce roadkill risk for abundant species on roads with a relatively high percentage of area with buildings in the Hainan tropical rainforest.]]></description>
      <pubDate>Mon, 23 Sep 2024 09:06:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2427933</guid>
    </item>
    <item>
      <title>Effectiveness of permanent drift fences in reducing roadkill risk of amphibians</title>
      <link>https://trid.trb.org/View/2418235</link>
      <description><![CDATA[Roads are an important source of human economic progress, but also a threat to wildlife populations and natural habitats. Roads are responsible for the direct mortality of hundreds of millions of animals worldwide, with special negative effects for amphibians. Since the middle of the twentieth century, various types of mitigation measures have been constructed to reduce the negative effects of roads. However, despite the large availability of potential solutions designed for this purpose, there is still a knowledge gap about their effectiveness for amphibians. This study analysed whether permanent concrete drift fences reduced the roadkill risk for amphibians. The authors applied a before-after-control-impact (BACI) design in two road segments with concrete drift fences for amphibians. The authors recorded amphibians on these road segments three years before and three years after the fence installation. The authors further tested whether the presence of these mitigation measures transferred the animals to sites adjacent to the drift fences, creating new potential mortality aggregation sites (fence-end effect). The authors' results show a significant reduction in the number of amphibians reaching the sites with the drift fences. The authors were, however, unable to demonstrate the potential movement route transference, as the authors' results were inconclusive. Despite the increase in amphibian numbers at the control sites in the first year after fence installation, the following two years presented similar amphibian numbers as the pre-fence years. The authors recognise the importance of permanent drift fences in reducing the mortality of amphibian populations; however, the authors encourage future studies to include tunnel-crossing data as well, to truly unveil the roadkill reduction power of amphibian mitigation measures, while maintaining or increasing connectivity between roadside habitats.]]></description>
      <pubDate>Thu, 22 Aug 2024 15:09:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2418235</guid>
    </item>
    <item>
      <title>Using the dead to infer about the living: Amphibian roadkill spatiotemporal dynamics suggest local populations' reduction</title>
      <link>https://trid.trb.org/View/2376442</link>
      <description><![CDATA[Roads represent one of the main sources of wildlife mortality, population decline, and isolation, especially for low-vagility animal groups. It is still not clearly understood how wildlife populations respond to these negative effects over space and time. Most studies on wildlife road mortality do not consider the spatial and temporal components simultaneously, or the imperfect roadkill detection, both of which could lead to inaccurate assumptions and unreliable mitigation actions. In this study, the authors applied a multi-season occupancy model to a 14-year amphibian mortality dataset collected along 120 km of roads, combined with freely available landscape and remote sensing metrics, to identify the spatiotemporal patterns of amphibian roadkill in a Mediterranean landscape in Southern Portugal. The models showed an explicit general decrease in amphibian roadkill. The Iberian painted frog (Discoglossus galganoi) experienced roadkill declines over time of ∼70 %, while the spiny common toad (Bufo spinosus) and the fire salamander (Salamandra salamandra) had a loss of nearly 50 %, and the Southern marbled newt (Triturus pygmaeus) had 40 %. Despite the decreasing trend in roadkill, spatial patterns seem to be rather stable from year to year. Multi-season occupancy models, when combined with relevant landscape and remote sensing predictors, as well as long-term monitoring data, can describe dynamic changes in roadkill over space and time. These patterns are valuable tools for understanding roadkill patterns and drivers in Mediterranean landscapes, enabling the differentiation of road sections with varying roadkill over time. Ultimately, this information may contribute to the development of effective conservation measures.]]></description>
      <pubDate>Mon, 17 Jun 2024 09:38:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2376442</guid>
    </item>
    <item>
      <title>Phenotypically plastic responses to freshwater salinization in larval amphibians: Induced tolerance and induced sensitivity</title>
      <link>https://trid.trb.org/View/2251566</link>
      <description><![CDATA[Contamination of aquatic ecosystems is pervasive around the world and there has been a growing interest in understanding the ecological and evolutionary impacts. For contaminants such as pesticides, researchers are discovering widespread evolution of increased tolerance in target and non-target species and the role of phenotypic plasticity in facilitating this evolution. In contrast, the authors know much less about the evolution of tolerance in response to the increasing problem of freshwater salinization. In amphibians, recent studies have discovered that some populations from ponds with high salt pollution (from deicing road salts) have evolved higher tolerance. In this study, the authors examined whether populations of wood frog tadpoles (Rana sylvatica) possess rapid, inducible tolerance to salinity in a manner similar to their inducible tolerance to pesticides. Using newly hatched tadpoles from nine populations, the authors discovered that eight of the populations were able to alter their tolerance to salt. However, seven of the eight inducible populations experienced a higher sensitivity to salt while the eighth population experienced a higher tolerance to salt. Such inducible responses likely reflect the interplay of salt dynamics in the ponds, combined with the available genetic variation and selection intensity of each pond. This appears to be the first example of inducible salt tolerance in any animal and future studies should examine the generality of the response and how it may affect the evolution of tolerance to the global issue of freshwater salinization.]]></description>
      <pubDate>Mon, 13 Nov 2023 09:01:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2251566</guid>
    </item>
    <item>
      <title>Potential hotspots of amphibian roadkill risk in Spain</title>
      <link>https://trid.trb.org/View/2197090</link>
      <description><![CDATA[The authors test a forecasting strategy to identify potential hotspots of amphibian roadkill, combining the spatial distribution of amphibians, their relative risk of collision with vehicles and data on road density in Spain. The authors extracted a large dataset from studies reporting road casualties of 39 European amphibian species and then estimated the ‘relative roadkill risk’ of species as the frequency of occurrence of casualties for each amphibian and standardized by the range of distribution of the species in Europe. Using a map with the spatial distribution of Spanish amphibians at a spatial resolution of 10 × 10 Km squares, the authors estimated the ‘cumulative relative risk of roadkill’ for each amphibian assemblage as the sum of risk estimates previously calculated for each species. The authors also calculated the total length of roads in each square (road density). Finally, combining all layers of information, the authors elaborated a forecasting map highlighting the potential amphibian roadkill risk across Spain. Our findings are relevant to suggest areas that should be focused on at more detailed spatial scales. Additionally, the authors found that the frequency of roadkill was unrelated to the evolutionary distinctiveness score and conservation status of amphibian species, while was positively correlated with their distribution range.]]></description>
      <pubDate>Tue, 29 Aug 2023 16:46:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2197090</guid>
    </item>
    <item>
      <title>Statewide prioritization of vernal pools for pond-breeding amphibians in New Jersey</title>
      <link>https://trid.trb.org/View/2166620</link>
      <description><![CDATA[Vernal pools are required habitat of pond-breeding amphibians, yet their legal protections in the United States are not established, leaving vernal pools vulnerable to development and habitat fragmentation. Seasonally, amphibians migrate to breed in vernal pools. Roads and upland forest loss can jeopardize that migration, resulting in mortality. Vernal pools surrounded by fewer roads and more upland forest are of greater preservation priority in the management of amphibian populations. This study presents a statewide preservation prioritization of New Jersey's 13,594 vernal pools mapped in a previous work. The prioritization builds on that work by calculating a preservation score based on a combination of six characteristics regarding habitat fragmentation in the migratory area surrounding a vernal pool. The scores are calculated at a range of migration distances to account for a variety of amphibian species, and it is found that the different distances make little difference to preservation scores because of the overall small scale at which amphibians migrate. Results are presented that show clear parts of the state that should be prioritized for vernal pool preservation, mainly in areas where fewer roads lead to less development and habitat fragmentation. Areas of preservation priority are further refined using geographic clusters which show assemblages of vernal pools with favorable migratory areas. A special class of vernal pools has migratory areas that are uninterrupted by roads. These vernal pools and the assemblages of favorable migratory areas are often in preserved lands, but those that are not should receive special attention in both the field confirmation of amphibian habitat and subsequent protective measures, which can vary from conservation easements to citizen science interventions in sustaining local amphibian populations. Furthermore, surrounding states that also have a significant amount of vernal pools may be able to use this prioritization framework for preservation and conservation.]]></description>
      <pubDate>Tue, 20 Jun 2023 10:09:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2166620</guid>
    </item>
    <item>
      <title>Research to Inform Passage Spacing for Migratory Amphibians and to Evaluate Efficacy and Designs for Open Elevated Road Segment (ERS) Passages</title>
      <link>https://trid.trb.org/View/2122540</link>
      <description><![CDATA[This research was conducted to: help inform the distances required between crossings to provide high permeability across roads for migratory amphibians (i.e., Yosemite toad), to assess the permeability of a new passage design for amphibians and other small animal species, and to provide engineering evaluation of this concept for primary roads and highways.  (1) Although the sample size was low due to severe drought conditions in the last two years of the study and sampling constraints, the authors found similarities between the fence movement behavior of Yosemite toads and other migratory amphibians. Approximately 90% of toads were estimated to move 20 m or more along the fence, with an average distance of 46 m before “giving up”. These preliminary results suggest that passages spaced within 20m of one another along Yosemite toad migratory pathways are likely to provide connectivity to 90% of the population. (2) Initial results of passage permeability showed that the elevated road segment (ERS) crossing has a high potential to provide increased connectivity for Yosemite toads and a wide range of other amphibian, reptile, and small mammal species while greatly reducing road mortality. (3) The ERS concept designs, engineering evaluation and guidance document for primary roads and highways provide a starting point for local and DOT engineers to design and build permanent ERS structure(s) to enhance the movement of small wildlife, particularly for, but not limited to, migrating amphibians over wide stretches of roadway.]]></description>
      <pubDate>Tue, 14 Mar 2023 15:10:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2122540</guid>
    </item>
    <item>
      <title>The effects of road salt (NaCl), predation, and competition on the growth and community interactions of spotted salamanders (Ambystoma maculatum) and wood frogs (Lithobates sylvaticus)</title>
      <link>https://trid.trb.org/View/2039117</link>
      <description><![CDATA[Road deicing salts are frequently used in northern regions of the world during the winter and early spring months. As a result, a significant portion of road runoff into surrounding aquatic habitats contains road deicing salts. Previous studies found road salt contaminations in vernal pools that pond-breeding amphibians commonly use, including spotted salamanders (Ambystoma maculatum) and wood frogs (Lithobates sylvaticus). Studies have examined the impact of road salt on both amphibian species, but to the authors' knowledge no previous studies have examined how road salt impacts the interspecific competition between both amphibians. The authors hypothesized that road salt would negatively impact growth and survivorship of both amphibian species. During the spring and summer of 2017, the authors conducted an outdoor mesocosm experiment in which the authors created eight experimental conditions with three main factors: presence/absence of NaCl (1000 mg/L Cl−), presence/absence of interspecific competition between the two amphibian species (A. maculatum and L. sylvaticus), and presence/absence of predatory dragonfly larvae (Family Libellulidae). The authors' experiment revealed that salt delayed hatching and increased deformity in spotted salamander hatchlings. Additionally, salt reduced salamander survivorship by 62% and frog survivorship by 30%. Wood frog tadpoles and road salt interacted to diminish salamander survivorship a further 80% beyond salt alone, likely through an increase in interspecific competition. Road salt increased the larval period of salamanders and decreased the proportion metamorphosed by the end of the experiment. Dragonfly larvae reduced salamander survivorship by 35%, whereas they increased wood frog tadpole development rates. Dragonfly larvae and salt interacted to alter tadpole denticle size, with salt negating the impact of dragonfly larvae. Thus, the authors found that salt interfered with aquatic predatory chemical cues. Overall, the results of this study suggest that management strategies should be implemented in order to reduce the impact of road salts on freshwater aquatic ecosystems.]]></description>
      <pubDate>Thu, 20 Oct 2022 10:23:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2039117</guid>
    </item>
    <item>
      <title>Assessing Traffic Threats for Amphibian and Reptile Species of Greatest Conservation Need on Texas Roadways: Final Report</title>
      <link>https://trid.trb.org/View/2040363</link>
      <description><![CDATA[Many environmental impacts involve state and federally listed threatened and endangered (TE) species. Wildlife-vehicle collision (WVC) data can improve environmental impact assessments for TE species. Accurate WVC data has been collected for amphibian and reptile species on Texas roadways since 2012, in the form of observations in the “Herps of Texas” project on the citizen science platform iNaturalist. These data were used to create a database of species of greatest conservation need (SGCN) recorded and verified in the state that was joined with Texas road traffic data from the Texas Department of Transportation (TxDOT) and used to evaluate SGCN species presence and mortality on and near roads. As of 3 April 2018, there were 11,527 Research Grade quality records of 62 SGCN species downloaded from the iNaturalist “Herps of Texas” project. Maps distinguishing live and dead SGCN Reptiles and Amphibians observations >100 m away from and 100 m within either side of 2,333 control sections across Texas are found in Appendix A of this report. There were 1,474 records of 44 SGCN near control sections with associated traffic data. The authors found shorter distances to roads, higher traffic volumes, latitude and longitude were important predictors of mortality in all SGCN observations together. With respect to environmental impacts involving state and federally listed TE species, the authors found that some amphibian and reptile species groups were more likely to complicate transportation project planning than others and for different reasons.]]></description>
      <pubDate>Mon, 17 Oct 2022 09:12:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2040363</guid>
    </item>
    <item>
      <title>Road salt is more toxic to wood frog embryos from polluted ponds</title>
      <link>https://trid.trb.org/View/1901183</link>
      <description><![CDATA[Organisms that rely on aquatic habitats in roaded landscapes face a growing array of consequences from pollution, especially due to freshwater salinization. Critically, these consequences can vary from population to population depending on exposure histories and evolutionary responses. Prior studies using transplant and common garden experiments have found that aquatic-stage wood frogs (Rana sylvatica) from roadside populations are less fit in the wild and more sensitive to road salt than their counterparts from woodland populations away from roads. While this pattern is consistent with local maladaptation, unresolved insights into the timing and duration of these effects leave open the possibility that negative outcomes are countered during development. Here, the authors asked whether the survival disadvantage of roadside wood frogs is stage specific, and whether this disadvantage reverses before metamorphosis. The authors used a common garden road salt exposure experiment and a field-based reciprocal transplant experiment to examine differences in survival across life-history stage and with respect to population type. In each experimental context, roadside embryos showed a survival disadvantage relative to woodland embryos, and this disadvantage was not reversed prior to metamorphosis. The authors also found that salt exposure delayed metamorphosis more strongly for roadside than woodland populations. Together, these results suggest that local maladaptation in aquatic-stage wood frogs is driven by embryonic sensitivity to salt and that roadside populations are further compromised by delayed developmental rates. Future studies should consider which embryonic traits fail to adapt to salt toxicity, and how those traits might correlate with terrestrial trait variation.]]></description>
      <pubDate>Tue, 25 Jan 2022 09:50:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1901183</guid>
    </item>
    <item>
      <title>Road salt compromises functional morphology of larval gills in populations of an amphibian</title>
      <link>https://trid.trb.org/View/1890344</link>
      <description><![CDATA[Across the planet, winter de-icing practices have caused secondary salinization of freshwater habitats. Many amphibians are vulnerable because of permeable skin and reliance on small ponds, where salinity can be high. Early developmental stages of amphibians are especially sensitive to salt, and larvae developing in salt-polluted environments must osmoregulate through ion exchange in gills. Though ionoregulation in amphibian gills is generally understood, the role of gill morphology remains poorly described. Yet gill structure should affect ionoregulatory capacity, for instance in terms of available surface area. Larval amphibian gills also play critical roles in gas exchange and foraging. Thus, changes in gill morphology from salt pollution potentially affect not only osmoregulation, but also respiration and feeding. Here, the authors used an exposure experiment to quantify salinity effects on larval gill morphology in wood frogs (Rana sylvatica). The authors measured a suite of morphological traits on gill tufts—where ionoregulation and gas exchange occur—and on gill filters used in feeding. Larvae raised in elevated salinity developed larger gill tufts but with lower surface area to volume ratio. Epithelial cells on these tufts were less circular but occurred at higher densities. Gill filters showed increased spacing, likely reducing feeding efficiency. Many morphological gill traits responded quadratically, suggesting that salinity might induce plasticity in gills at intermediate concentrations until energetic demands exceed plasticity. Together, these changes likely diminish ionoregulatory and respiratory functionality of gill tufts, and compromise feeding functionality of gill filters. Thus, a singular change in aquatic environment from a widespread pollutant appears to generate a suite of consequences via changes in gill morphology. Critically, these changes in traits likely compound the severity of fitness impacts in populations dwelling in salinized environments, whereby ionoregulatory energetic demands should increase respiratory and foraging demands, but in individuals who possess structures poorly adapted for these functions.]]></description>
      <pubDate>Wed, 17 Nov 2021 14:25:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1890344</guid>
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