Science Enabled by Specimen Data

Venegas-Barrera, C. S., J. Manjarrez, Á. Rodríguez-Moreno, Y. A. Mendoza-Walle, J. V. Horta-Vega, I. R. Rodríguez-deLeón, A. Sunny, and A. Azuara Domínguez. 2024. Representativeness, Complementarity, and Degree of Local Extirpation Risk for Thamnophis Species Inside and Outside of Protected Areas of Mexico. Ecologies 5: 697–715. https://doi.org/10.3390/ecologies5040041

Protected areas (PAs) are geographical spaces intended to conserve populations, communities, and ecosystems, in which species richness must be maximized, the conserved area must be minimized, and anthropogenic pressure must be reduced. The present study analyzed the representativeness, complementarity, and degree of risk of 25 garter snake species of the genus Thamnophis in the PAs of Mexico. This study proposes that at least 17% of the potential geographic distribution (PGD) of species will be found inside PAs and in areas (Aichi Target 11) with a low human footprint (HF). The PGD of species was associated with the PAs and HF layers to identify where and which species could be at local extirpation risk by human activities. The results indicate that the federal PAs contain 85.2% of the species, while the state PAs contain 77.7% of the species. An average of 13.4% of the PGD of these species is found inside PAs, and two species are found outside. In 13 federal PAs and 10 state PAs, the Thamnophis species present high local extirpation risk from human activities. In total, 37% of species are found in PAs with a medium to very high human footprint; therefore, their persistence could be at local extirpation risk. Compared to other taxa, species of the genus Thamnophis are well represented. However, the PDG of more than half of the species achieves Aichi Target 11.

Pilliod, D. S., M. I. Jeffries, R. S. Arkle, and D. H. Olson. 2024. Climate Futures for Lizards and Snakes in Western North America May Result in New Species Management Issues. Ecology and Evolution 14. https://doi.org/10.1002/ece3.70379

We assessed changes in fundamental climate‐niche space for lizard and snake species in western North America under modeled climate scenarios to inform natural resource managers of possible shifts in species distributions. We generated eight distribution models for each of 130 snake and lizard species in western North America under six time‐by‐climate scenarios. We combined the highest‐performing models per species into a single ensemble model for each scenario. Maps were generated from the ensemble models to depict climate‐niche space for each species and scenario. Patterns of species richness based on climate suitability and niche shifts were calculated from the projections at the scale of the entire study area and individual states and provinces, from Canada to Mexico. Squamate species' climate‐niche space for the recent‐time climate scenario and published known ranges were highly correlated (r = 0.81). Overall, reptile climate‐niche space was projected to move northward in the future. Sixty‐eight percent of species were projected to expand their current climate‐niche space rather than to shift, contract, or remain stable. Only 8.5% of species were projected to lose climate‐niche space in the future, and these species primarily occurred in Mexico and the southwestern U.S. We found few species were projected to lose all suitable climate‐niche space at the state or province level, although species were often predicted to occupy novel areas, such as at higher elevations. Most squamate species were projected to increase their climate‐niche space in future climate scenarios. As climate niches move northward, species are predicted to cross administrative borders, resulting in novel conservation issues for local landowners and natural resource agencies. However, information on species dispersal abilities, landscape connectivity, biophysical tolerances, and habitat suitability is needed to contextualize predictions relative to realized future niche expansions.

Ascanio, A., J. T. Bracken, M. H. H. Stevens, and T. Jezkova. 2024. New theoretical and analytical framework for quantifying and classifying ecological niche differentiation. Ecological Monographs. https://doi.org/10.1002/ecm.1622

Ecological niche differentiation is a process that accompanies lineage diversification and community assembly. Traditionally, the degree of niche differentiation is estimated by contrasting niche hypervolumes of two taxa, reconstructed using ecologically relevant variables. These methods disregard the fact that niches can shift in different ways and directions. Without means of discriminating between different types of niche differentiation, important evolutionary and ecological patterns may go unrecognized. Herein, we introduce a new conceptual and methodological framework that allows quantification and classification of niche differentiation and divergence between taxa along single niche axis. This new method, the Niche Divergence Plane, is based on species' responses to an underlying environmental gradient, from which we derive a two‐dimensional plane defined by two indices, niche exclusivity and niche dissimilarity. These two indices identify the proportion of the environmental gradient that is unique to each species, that is, how much of the environmental gradient species do not share (niche breadth exclusivity) and how different the species' responses are along the environmental gradient (niche dissimilarity). Thus, the latter can also be seen as a measure of the differences in niche preference or importance, even when there is significant overlap in niche breadth (i.e., low niche exclusivity). Based on the position of the two indices on the divergence plane, we can distinguish niche conservatism from four other general types of niche divergence: hard, soft, weighted, and nested. We demonstrate that the Niche Divergence Plane complements traditional measures of niche similarity (e.g., Schoener's D or Hellinger's I). Additionally, we show an empirical comparison using the Niche Divergence Plane framework on two Ambystoma salamanders. Overall, we demonstrate that the Niche Divergence Plane is a versatile tool that can be used to complement and expand previous methods of ecological niche comparisons and the study of ecological niche divergence.

Thonis, A., A. Stansfield, and H. R. Akçakaya. 2024. Unravelling the role of tropical cyclones in shaping present species distributions. Global Change Biology 30. https://doi.org/10.1111/gcb.17232

Driven by climate change, tropical cyclones (TCs) are predicted to change in intensity and frequency through time. Given these forecasted changes, developing an understanding of how TCs impact insular wildlife is of heightened importance. Previous work has shown that extreme weather events may shape species distributions more strongly than climatic averages; however, given the coarse spatial and temporal scales at which TC data are often reported, the influence of TCs on species distributions has yet to be explored. Using TC data from the National Hurricane Center, we developed spatially and temporally explicit species distribution models (SDMs) to examine the role of TCs in shaping present‐day distributions of Puerto Rico's 10 Anolis lizard species. We created six predictor variables to represent the intensity and frequency of TCs. For each occurrence of a species, we calculated these variables for TCs that came within 500 km of the center of Puerto Rico and occurred within the 1‐year window prior to when that occurrence was recorded. We also included predictor variables related to landcover, climate, topography, canopy cover and geology. We used random forests to assess model performance and variable importance in models with and without TC variables. We found that the inclusion of TC variables improved model performance for the majority of Puerto Rico's 10 anole species. The magnitude of the improvement varied by species, with generalist species that occur throughout the island experiencing the greatest improvements in model performance. Range‐restricted species experienced small, almost negligible, improvements but also had more predictive models both with and without the inclusion of TC variables compared to generalist species. Our findings suggest that incorporating data on TCs into SDMs may be important for modeling insular species that are prone to experiencing these types of extreme weather events.

DuBose, T. P., V. Catalan, C. E. Moore, V. R. Farallo, A. L. Benson, J. L. Dade, W. A. Hopkins, and M. C. Mims. 2024. Thermal Traits of Anurans Database for the Southeastern United States (TRAD): A Database of Thermal Trait Values for 40 Anuran Species. Ichthyology & Herpetology 112. https://doi.org/10.1643/h2022102

Thermal traits, or how an animal responds to changing temperatures, impacts species persistence and thus biodiversity. Trait databases, as repositories of consolidated, measured organismal attributes, allow researchers to link study species with specific trait values, enabling comparisons within and among species. Trait databases also help lay the groundwork to build mechanistic linkages between organisms and the environment. However, missing or hidden physiological trait data preclude building mechanistic estimates of climate change vulnerability for many species. Thus, physiologically focused trait databases present an opportunity to consolidate data and enable species-specific or multispecies, mechanistic evaluations of climate change vulnerability. Here, we present TRAD: thermal traits of anurans database for the southeastern United States, a database of thermal trait values related to physiological thermoregulation (critical thermal minima and maxima, preferred temperature), behavioral thermoregulation (activity period, retreat emergence temperature, basking temperature, minimum and maximum foraging temperatures), and body mass for 37 anuran species found within the southeastern United States. In total, TRAD contains 858 reported trait values for 37 of 40 species found in the region from 267 peer-reviewed papers, dissertations, or theses and is easily linked with trait data available in ATraiU, an ecological trait database for anurans in the United States. TRAD contains trait values for multiple life stages and a summarization of interspecific adult trait values. Availability of trait data varied widely among traits and species. Estimates of mass were the most common trait values reported, with values available for 32 species. Behavioral trait values comprised 23% of our database, with activity period available for 34 species. We found the most trait values for Cope's Gray Treefrog (Dryophytes chrysoscelis), with at least one trait value for eight traits in the database. Conversely, species in the genus Pseudacris generally had the fewest trait values available. Species with the largest geographic range sizes also had the greatest coverage of data across traits (rho 5 0.75, P , 0.001). TRAD can aid studies of anuran response to changing temperatures, physiological niche space and limitations, and potential drivers of anuran geographic range limits, influencing our understanding of other ecological and evolutionary patterns and processes and enabling multispecies comparisons of potential risk and resilience in the face of climate change.

Lin, Z., Y. Hong, S. Chen, Q. Zhang, L. Han, W. Tu, Y. Du, et al. 2023. Emerging non-native amphibians require immediate prevention management in a megacity of South China. BioInvasions Records 12: 731–744. https://doi.org/10.3391/bir.2023.12.3.09

Biological invasion is one serious threat to global biodiversity, economics and sustainability. Under the era of globalization, emerging non-native species are still accelerating at an unprecedented rate. Identifying new field records of non-native species at early stages is critically important to develop effective prevention and management schemes. Here, we conducted field surveys and applied genetic analysis to identify new recordings of non-native amphibians in Shenzhen (a megacity of South China with enormous trade volume). We recorded a total of three non-native amphibians (Ceratophrys ornata, Hoplobatrachus rugulosus and Eleutherodactylus planirostris) in the field with two having establishment evidence (H. rugulosus and E. planirostris). Further ecological niche modeling based on climatic and habitat variables also detected a high habitat suitability of the two species with field establishment evidence and a low habitat suitability for the other three species (C. ornata, Rana catesbeiana and Xenopus laevis) lacking establishment evidence or field observation with only records in the market and database. We recommend more systematic surveys covering wider areas to investigate the establishment of non-native amphibians to stop their further invasions in China.

Hedrick, B. P., A. Estrada, C. Sutherland, and A. M. Barbosa. 2023. Projected northward shifts in eastern red‐backed salamanders due to changing climate. Ecology and Evolution 13. https://doi.org/10.1002/ece3.9999

Many species' distributions are being impacted by the acceleration of climate change. Amphibians in particular serve numerous ecosystem functions and are useful indicators of environmental change. Understanding how their distributions have been impacted by climate change and will continue to be impacted is thus important to overall ecosystem health. Plethodon cinereus (Eastern Red‐Backed Salamander) is a widespread species of lungless salamander (Plethodontidae) that ranges across northeastern North America. To better understand future potential lungless salamander range shifts, we quantify environmental favorability, the likelihood of membership in a set of sites where environmental conditions are favorable for a species, for P. cinereus in multiple time periods, and examine shifts in the species' distribution. First, utilizing a large data set of georeferenced records, we assessed which bioclimatic variables were associated with environmental favorability in P. cinereus. We then used species distribution modeling for two time periods (1961–1980 and 2001–2020) to determine whether there was a regional shift in environmental favorability in the past 60 years. Models were then used to project future distributions under eight climate change scenarios to quantify potential range shifts. Shifts were assessed using fuzzy logic, avoiding thresholds that oversimplify model predictions into artificial binary outputs. We found that P. cinereus presence is strongly associated with environmental stability. There has been a substantial northward shift in environmental favorability for P. cinereus between 1961–1980 and 2001–2020. This shift is predicted to continue by 2070, with larger shifts under higher greenhouse gas emission scenarios. As climate change accelerates, it is differentially impacting species but has especially strong impacts on dispersal‐limited species. Our results show substantial northward shifts in climatic favorability in the last 60 years for P. cinereus, which are likely to be exacerbated by ongoing climate change. Since P. cinereus is dispersal‐limited, these models may imply local extirpations along the southern modern range with limited northward dispersal. Continued monitoring of amphibians in the field will reveal microclimatic effects associated with climate change and the accuracy of the model predictions presented here.

Gainsbury, A. M., E. G. Santos, and H. Wiederhecker. 2022. Does urbanization impact terrestrial vertebrate ectotherms across a biodiversity hotspot? Science of The Total Environment 835: 155446. https://doi.org/10.1016/j.scitotenv.2022.155446

Urbanization is increasing at an alarming rate altering biodiversity. As urban areas sprawl, it is vital to understand the effects of urbanization on biodiversity. Florida is ideal for this research; it has many reptile species and has experienced multiple anthropogenic impacts. Herein, we aim to evaluate human impacts on registered reptile richness across an urbanization gradient in Florida. The expectation is that highly urbanized areas would harbor a lower number of species. To represent urbanization, we used Venter et al. (2016) human footprint index. We downloaded georeferenced occurrence records from the Global Biodiversity Information Facility to collate species richness. We ran generalized linear regressions controlling for spatial autocorrelation structure to test the association between urbanization and reptile records across Florida. We found a positive association between urbanization and registered reptiles across Florida for total and non-native species richness; however, a lack of association occurred for native species. We performed rarefaction curves due to an inherent bias of citizen science data. The positive association was supported for non-native reptile species richness with greater species richness located at urban centers. Interestingly, total and native species richness were largest at low as well as moderate levels of urbanization. Thus, moderately urbanized areas may have the potential to harbor a similar number of reptile species compared to areas with low urbanization. Nevertheless, a difference exists in sample completeness between the urbanization categories. Thus, a more systematic monitoring of reptile species across an urbanization gradient, not only focusing on urban and wild areas but also including moderate levels of urbanization, is needed to provide informed conservation strategies for urban development planning. Advances in environmental sensors, environmental DNA, and citizen science outreach are necessary to implement if we are to effectively monitor biodiversity at the accelerated rate of urbanization.

Mu, C., X. Guo, and Y. Chen. 2022. Impact of Global Climate Change on the Distribution Range and Niche Dynamics of Eleutherodactylus planirostrish in China. Biology 11: 588. https://doi.org/10.3390/biology11040588

Species distribution models (SDMs) have become indispensable tools in risk assessment and conservation decision-making for invasive species. Eleutherodactylus planirostris has a strong dispersal ability, and the main route of introduction to new regions is likely transport via seedlings. This species is understood as one of the foremost successful invasive amphibian species with direct or indirect negative impacts in multiple regions. In this study, we used MaxEnt to assess suitable areas for this species under current and future climates globally and in China. We considered seven climatic variables, three timepoints (current, 2050, and 2070), and three CO2 emission scenarios. Annual mean temperature, precipitation of the driest month, and annual precipitation were the most important variables predicting E. planirostris occurrence. This species has a much larger suitable habitat area in China than reflected by the current distribution, so the species is likely to spread from the Pearl River Delta to surrounding areas. Under future warming, its invasive range will expand northward in China. In conclusion, this study assessed the risk of invasion of this species and made recommendations for management and prevention.

Radomski, T., S. R. Kuchta, and K. H. Kozak. 2022. Post‐Pleistocene dispersal explains the Rapoport effect in North American salamanders. Journal of Biogeography 49: 1048–1060. https://doi.org/10.1111/jbi.14361

Aims In many taxa, the latitudinal span of species' geographic ranges are positively correlated with median latitude (the Rapoport effect). This correlation is frequently explained as adaptation to contemporary climate; however, variability in post-glacial range expansion among species could also explain this observation. We analyse geographic data for North American salamanders to test the potential causes of Rapoport effects. Location Temperate North America. Taxon Salamanders (order Caudata). Methods We tested for a Rapoport effect by estimating correlations between the latitudinal midpoint and latitudinal range among species. Next, we manipulated species' latitudinal ranges by removing post-glacial habitat and assessing the impact of species demonstrating post-glacial range expansion in forming a Rapoport effect. We built ecological niche models for species found south of the Wisconsin Ice Sheet during the Last Glacial Maximum and transferred these models to post-glacial areas. If dispersal is important in forming a Rapoport effect, then some species may tolerate northern climates but have not expanded northward as a result of variation in geographic access to post-glacial habitats. We created binary ecological niche models by thresholding using the equal sensitivity and specificity value. Results We recovered a Rapoport effect that was robust to the null models we tested. Analyses that manipulated ranges and species pools supported a role for variation in post-glacial range expansion among species, especially for eastern North America. Results from transferring ecological niche models indicated that species have suitable habitat north of their range limit. Main conclusions Variation in post-glacial range expansion is important in shaping geographic range size clines among species in areas where climates changed rapidly, though we also found support for the climatic variability hypothesis. Post-glacial colonization and range expansion likely plays an important role in forming latitudinal biodiversity gradients in northern taxa. While ecophysiology and biotic interactions have been emphasized as important contributors to diversity gradients, our study indicates that post-glacial colonization also plays a key role in forming latitudinal gradients.