Find research datasets worth reusing

opencc-by-4.0Aug 2017View details →

Fig. 8 in Eight Species Of Anuran Amphibians (Amphibia, Anura) Found In Ukraine: Comparative Morphology And Classification Of Larval Development Stages

Fig. 8. Dynamics of four species' anuran amphibians body linear parameters.

opencc-by-4.0Mar 2015View details →

Fig. 5 in Using Ecological Niche Modeling For Biodiversity Conservation Guidance In The Western Podillya (Ukraine): Amphibians

Fig. 5. Summarized species richness map (see text for explanation).

opencc-zeroJun 2022View details →

Wildfire influences individual growth and breeding dispersal, but not survival and recruitment in a montane amphibian

Global wildfire regimes are changing rapidly, with widespread increases in the size, frequency, duration, and severity of wildfires. Whereas the effects of wildfire on ecological state variables such as occupancy, abundance, and species diversity are relatively well-documented, changes in population vital rates (e.g., survival, recruitment) and individual responses (e.g., growth, movement) to wildfire are more limited because of the detailed information needed on the same individuals both pre- and post-fire. We capitalized on the 2018 Roosevelt wildfire, which occurred during our six-year (2015–2020) capture-mark-recapture study of boreal toads (Anaxyrus boreas boreas; n = 1415) in the Bridger-Teton National Forest, USA, to evaluate the responses of population vital rates and individual metrics to wildfire. We employed robust design capture-recapture models to compare the growth, dispersal, survival, and recruitment of adult boreal toads pre- and post-fire at burned versus unburned sites. At burned locations, growth increased two-years post-fire compared with the year directly following wildfire and was higher two-years post-fire than any other interval during our study period. Boreal toads dispersed to alternative breeding patches more at burned sites than unburned sites and dispersal increased two-years post-fire compared with the year directly following wildfire. Annual survival and recruitment did not differ between pre- and post-fire years nor among pre-fire years, the year following wildfire, and two-years post-fire. We demonstrate that, in certain contexts, dispersal can play a major role in changes to state variables (e.g., abundance) after wildfire, as opposed to other vital rates such as survival and recruitment. Our study represents an important step towards understanding the biological processes that underlie observed patterns in state variables following wildfire, which ultimately will be critical for the effective management of species in landscapes experiencing shifts in fire activity.

opencc-zeroJul 2022View details →

Salamanders reveal novel trajectories of amphibian MHC evolution

Genes of the Major Histocompatibility Complex (MHC) code for immune proteins that are crucial for pathogen recognition in vertebrates. MHC research in non-model taxa has long been hampered by its genomic complexity that makes the locus-specific genotyping challenging. The recent progress in sequencing and genotyping methodologies allows an extensive phylogenetic coverage in studies of MHC evolution. Here, we analysed the peptide-binding region of MHC class I in 30 species of salamanders from six families representative of Urodela phylogeny. This extensive dataset revealed an extreme diversity of MHC-I in salamanders, both in terms of sequence diversity (ca. 3000 variants) and architecture (2-22 gene copies per species). The signal of positive selection was moderate and consistent between both peptide binding domains, but varied greatly between genera. Positions of positively selected sites mostly coincided with human Peptide Binding Sites, suggesting similar structural properties of MHC-I molecules across distant vertebrate lineages. Finally, we provided evidence for the common intra-exonic recombination at MHC-I and for the role of life-history traits in the processes of MHC-I expansion/contraction. Our study revealed novel evolutionary trajectories of amphibian MHC and it contributes to the understanding of the mechanisms that generated extraordinary MHC diversity throughout vertebrate evolution.

opencc-zeroJul 2022View details →

Artificial displacement alters movement behavior of a terrestrial amphibian

Homing abilities have been widely documented in amphibians, but it remains unclear whether individuals have homing tendencies in the absence of motivational cues related to breeding and site fidelity. We tested whether artificial displacement would affect the movement behavior of a nonphilopatric terrestrial amphibian, the Fowler's Toad (Anaxyrus fowleri), within its home range and after its breeding season had ended. We translocated 65 male and female Fowler's Toads from their initial points of capture a total of 104 times over one of three different distances (100 m, 250 m, and 500 m) and compared these toads' subsequent 24-h movements with those of a control group of 43 untranslocated toads. To shield the translocated toads from auditory, visual, and olfactory cues en route, we translocated them in opaque enclosed boxes and performed the experiment in the uniformly unobstructed landscape of the Lake Erie shoreline of Long Point, ON, Canada. We mainly investigated directionality bias as the orientation between control and translocated groups, homing tendency as the correlation between movements after translocation and translocation distance, and homing accuracy as the variation in distance between final and initial capture points. Our results provide clear evidence that translocation changes the movement behavior of these toads and that they possess homing tendencies outside of their breeding season. Toads had a strong directional bias to move in the opposite direction to the one in which they were artificially displaced, in contrast with the control group, which showed no directional bias among 61 recorded 24-h movements. This tendency for amphibians to home after artificial displacement might be a significant confounding factor in any procedure involving their relocation.

opencc-zeroAug 2022View details →

Determinants of genetic diversity and species richness of North American amphibians

Aim: Ecological limits on population sizes and the number of species a region can sustain are thought to simultaneously produce spatial patterns in population genetic diversity and species richness due to the effects of random drift operating in parallel across population and community levels. Here, we test the extent to which resource-based environmental limits jointly determine these patterns of biodiversity in amphibians. Location: North America. Taxon: Amphibians. Methods: We repurposed open, raw microsatellite data from 19 species sampled at 554 sites in North America and mapped nuclear genetic diversity at the continental scale. We then tested whether ecological limits defined by resource availability and environmental heterogeneity could simultaneously shape biogeographic patterns in genetic diversity and species richness with structural equation modeling. Results: Spatial patterns of population genetic diversity run opposite patterns of species richness and genetic differentiation. However, while measures of resource availability and niche heterogeneity predict 89% of the variation in species richness, these landscape metrics were poor predictors of genetic diversity. Main conclusions: Although heterogeneity appears to be an important driver of genetic and species biodiversity patterns in amphibians, variation in genetic diversity both within and across species makes it difficult to infer general processes producing spatial patterns of amphibian genetic diversity. This result differs from those found in endotherms and may be due to the considerable life history variation found across amphibians.

opencc-by-4.0Dec 2022View details →

How extreme drought events , introduced species, and disease interact to impact influence threatened amphibian populations

Long term dataset of amphibian breeding in the Bay Area of California. We used this  7-y dataset (2013–2019) on amphibian breeding activity that encompassed a recent extreme drought event to assess 1) how breeding activities of these taxa differed during and after drought conditions and 2) the additive and interactive relationships of drought, chytrid fungal infection (Bd), and invasive species with the presence and abundance of larval amphibians.

opencc-by-4.0Jun 2023View details →

Conservation networks do not match ecological requirements of amphibians

Supplementary files of the paper Matutini et al. 2023 (https://doi.org/10.1101/2022.07.18.500425) Dataset sample and R script

opencc-zeroSep 2022View details →

Do functional and phylogenetic nestedness follow the same mechanisms as taxonomic nestedness? Evidence from amphibians in the largest archipelago of China

1. Nested subset pattern (nestedness) has been raised to explain the distribution of species on islands and habitat fragments for over 60 years. However, previous studies on nestedness focused on species richness and composition and overlooked the role of species traits and phylogeny in generating and explaining the nestedness. 2. To address this gap, we sampled amphibians on 37 land-bridge islands in the Zhoushan Archipelago to explore nestedness as well as the underlying causal processes through three facets of diversity, i.e. taxonomic, functional and phylogenetic diversity. The taxonomic nestedness was measured through organizing the species incidence matrix to achieve a maximum value, while the functional and phylogenetic nestedness were quantified by incorporating the similarity of species in terms of their ecological traits and phylogeny. We also obtained six island characteristics and seven species traits as predictors of nestedness. 3. Amphibian metacommunities were significantly nested in these three facets of diversity. When relating different predictors to nestedness, island area, habitat diversity and species traits were highly correlated with taxonomic nestedness. Moreover, island area and habitat diversity significantly influenced functional and phylogenetic nestedness. Therefore, the results support the selective extinction and habitat nestedness hypotheses. 4. Interestingly, although we did not observe significant influences of isolation on taxonomic nestedness, functional and phylogenetic diversities were significantly higher than expected when matrices were ordered by increasing distance to mainland. The result suggests that there are more functionally and phylogenetically diverse species on less-isolated islands, reflecting a selective colonization process overlooked by the traditional analysis of taxonomic nestedness. 5. Although the three facets of nestedness and underlying processes were largely congruent, we detected the distance-related functional and phylogenetic nestedness for amphibian assemblages. Therefore, we highlight that a framework that simultaneously considers taxonomic, functional and phylogenetic nestedness contributes to a complementary understanding of nestedness processes. In addition, it also improves our ability to conserve insular biodiversity from different perspectives.

opencc-zeroDec 2021View details →

Elevational range of mammals, birds, and amphibians in the Himalayas

The lowest and highest elevations known for each species are used to delineate its elevational limits. We assume that species potentially exist between their elevational limits. For species that have a single elevational distribution record (resulting in an elevational range of zero) as well as those with elevational ranges less than 200 m, we adjusted their elevation ranges to 200 m. We verified all data for accuracy by experts within the region and any dubious outlying records were removed. Elevational limits were given for 1,488 species, including 314 mammals, 1027 birds, and 147 amphibians in the Himalayas.

opencc-zeroOct 2022View details →

Compensatory recruitment unlikely in high elevation amphibian populations challenged with disease

Population-level variation in host responses to disease can be observed across a wide array of host-pathogen systems. Some host populations are extirpated, some persist at lower densities or abundances, and others rebound to pre-disease levels. Understanding the causes of this variation, and the mechanisms of successful persistence, can serve as vital information for species conservation. One such mechanism of population persistence that has gained support in the amphibian Batrachochytrium dendrobatidis (Bd) host-pathogen system is the demographic process of compensatory recruitment. Host populations may persist by increasing recruitment to compensate for reduced survival due to infection, thus limiting the negative effects of the disease on population trajectories. However, high-elevation amphibian populations are inherently vulnerable to stochastic processes and may be limited in their ability to exhibit compensatory recruitment relative to lower-elevation populations. We use long-term mark-recapture data from five populations of boreal toads (Anaxyrus boreas boreas), across an elevational gradient in Colorado, before and after pathogen arrival to assess whether populations can persist with Bd via compensatory recruitment. Prior to Bd arrival, we found a life history tradeoff between survival and recruitment across elevations, where high-elevation toads have high survival but lower recruitment and vice versa at lower elevations. Bd arrival had a strong negative effect on apparent annual survival and recruitment, and led to negative population growth rates and dramatically reduced host abundances. The data did not support the occurrence of compensatory recruitment. Synthesis and applications. Our unique dataset suggests that demographic responses to pathogens may be environmentally (i.e., elevationally) context-dependent and highlights the value of long-term monitoring. We recommend that practitioners verify that potential persistence mechanisms occur across multiple populations and relevant environmental gradients to counter any assumptions of the mechanism existing species-wide. Quantifying any variation in population responses to disease will aid in understanding the bounds of such persistence mechanisms, and identify particularly vulnerable populations where mechanisms are non-existent.

Figure 3 in Identification key for anuran amphibians in a protected area in the northeastern Atlantic Forest

Figure 3. Discrete characters used in the identification key for the anuran amphibians occurring in the Environmental Protection Area of Catolé and Fernão Velho, Alagoas state, northeast Brazil. The details of characters are mentioned in the taxonomic key.

Figure 1 in Identification key for anuran amphibians in a protected area in the northeastern Atlantic Forest

Figure 1. Discrete characters used in the identification key for the anuran amphibians occurring in the Environmental Protection Area of Catolé and Fernão Velho, Alagoas state, northeastern Brazil. Dorsal skin texture. (A) warty; (B) spiculate; (C) granular; (D) smooth; (E) shagreened; (F) tubercular.

Figure 2 in Identification key for anuran amphibians in a protected area in the northeastern Atlantic Forest

Figure 2. Discrete characters used in the identification key for the anuran amphibians occurring in the Environmental Protection Area of Catolé and Fernão Velho, Alagoas state, northeast Brazil. The details of characters are mentioned in the taxonomic key.

Figure 4 in Identification key for anuran amphibians in a protected area in the northeastern Atlantic Forest

Figure 4. Discrete characters used in the identification key for anuran amphibians occurring in the Environmental Protection Area of Catolé and Fernão Velho, Alagoas state, northeastern Brazil. The details of characters are mentioned in the taxonomic key.

opencc-zeroApr 2024View details →

Wetland creation and reforestation of legacy surface mines in the Central Applachian Region (USA): A potential climate-adaptation approach for pond-breeding amphibians?

Habitat restoration and creation within human-altered landscapes can buffer the impacts of climate change on wildlife. The Forestry Reclamation Approach (FRA) is a coal surface mine reclamation practice that enhances reforestation through soil decompaction and the planting of native trees. Recently, wetland creation has been coupled with FRA to increase habitat available for wildlife, including amphibians. Our objective was to evaluate the response of pond-breeding amphibians to the FRA by comparing species occupancy, richness, and abundance across two FRA age-classes (2–5-year and 8–1—year reclaimed forests), traditionally reclaimed sites that were left to naturally regenerate after mining, and in mature, unmined forests in the Monongahela National Forest (West Virginia, USA). We found that species richness and occupancy estimates did not differ across treatment types. Spotted Salamanders (Ambystoma maculatum) and Eastern Newts (Notophthalmus viridescens) had the greatest estimated abundances in wetlands in the older FRA treatment. Additionally, larger wetlands had greater abundances of Eastern Newts, Wood Frogs (Lithobates sylvaticus), and Green Frogs (L. clamitans) compared to smaller wetlands. Our results suggest that wetland creation and reforestation increases the number of breeding sites and promotes microhabitat and microclimate conditions that likely maximize the resilience of pond-breeding amphibians to anticipated climate changes in the study area.

opencc-zeroApr 2024View details →

Data from: Influences of ski-runs, meadow management and climate on the occupancy of reptiles and amphibians in a high-altitude environment of Italy

Alpine ecosystems harbour a rich and highly-specialized biodiversity which is particularly susceptible to anthropogenic disturbances such as habitat loss and fragmentation as well as to climate change. Combined with other forms of land-use conversion, construction and maintenance of ski resorts can have severe consequences on alpine biodiversity. In this study, we show how one amphibian and two reptile species, namely Rana temporaria, Zootoca vivipara and Vipera berus, respond to such impacts by means of a multi-season occupancy analysis. We found all three species both in and outside ski-runs, showing that these habitats do not necessarily preclude their occurrence. Contrarily, this is influenced more by microhabitat availability, such as ground vegetation, humid areas, and rock cover, rather than by macro-characteristics like elevation or habitat type. Moreover, we found a climatic influence on the year-to-year occupancy change of the species, with activity-months conditions being more relevant than overwintering ones. Our results demonstrate how, in the specific case of reptiles and amphibians, ski resorts do not necessarily limit species' occurrence and that a mild series of management actions might secure the species' persistence in the area.

opencc-zeroMay 2024View details →

Data from: Vertical niche usage and trait associations in Gabonese amphibians

Tropical forests are vertically complex, and offer unique niche opportunities in the form of resource, climate, and habitat-gradients from the forest floor to the canopy. Rainforest amphibians organize within this vertical space and the highest levels of vertical stratification occur in structurally complex and climatically stable tropical rainforests. Amphibians have diversified into numerous habitat and climatic niches, which has led to the development of a wide variety of morphological, behavioural, physiological, and reproductive traits. However, a lack of data regarding the vertical niche space used by amphibian species has prevented a nuanced analysis of traits and vertical height. We performed 74 ground-to-canopy surveys for amphibians at Baposso Village, Ngounie Province, Gabon, and describe the vertical stratification patterns of the assemblage in terms of richness, abundance, and species specific vertical niche usage. We analyse the relationships between amphibian traits with vertical height using linear mixed effects models, finding strong support that frogs with bigger toes in relation to their length access greater height in the canopy. We also see differences in the vertical heights of species according to their reproductive modes, highlighting the importance of reproductive mode diversity for the vertical stratification of amphibian assemblages.

opencc-by-4.0Jun 2021View details →

Fig. 4 in Amphibian diversity of a West African biodiversity hotspot: an assessment and commented checklist of the batrachofauna of the Ivorian part of the Nimba Mountains

Fig. 4. Lower to mid-elevation dense, evergreen forest (habitat C) at 847 m asl.