skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: The impact of climate change on western Plethodon salamanders’ distribution
Abstract AimGiven that salamanders have experienced large shifts in their distributions over time, we determined how each species ofPlethodonin the Pacific Northwest would respond to climate change. We incorporated several greenhouse scenarios both on a species‐by‐species basis, and also using phylogenetic groups, with the aim to determine the best course of action in managing land area to conserve diversity in this group. LocationPacific Northwest of the United States (northern CA, OR, WA, ID, and MT). Major taxa studiedWesternPlethodonsalamanders. MethodsSpecies distribution models were estimated using MaxEnt for the current time period and for several future climate scenarios using bioclimatic data layers. We used several methods to quantify the change in habitat suitability over time from the models. We explored aspects of the climate layers to determine whether we can expect a concerted response to climate change due to similarity in ecological niche or independent responses that could be harder to manage. ResultsThe distribution of westernPlethodonsalamander species is strongly influenced by precipitation and less so by temperature. Species responses to climate change resulted in both increases and decreases in predicted suitable habitat, though most species ranges do not contract, especially when taken as a phylogenetic group. Main conclusionsWhile some established habitats may become more or less climatically suitable, the overall distribution of species in this group is unlikely to be significantly affected. Clades ofPlethodonspecies are unlikely to be in danger of extirpation despite the possibility that individual species may be threatened as a result of limited distributions. Grouping species into lineages with similar geographic ranges can be a viable method of determining conservation needs. More biotic and dispersal information is needed to determine the true impact that changes in climate will have on the distribution ofPlethodonspecies.  more » « less
Award ID(s):
1911293
PAR ID:
10449371
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Volume:
11
Issue:
14
ISSN:
2045-7758
Format(s):
Medium: X Size: p. 9370-9384
Size(s):
p. 9370-9384
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract ContextClimate change is altering suitable habitat distributions of many species at high latitudes. Fleshy fruit-producing plants (hereafter, “berry plants”) are important in arctic food webs and as subsistence resources for human communities, but their response to a warming and increasingly variable climate at a landscape scale has not yet been examined. ObjectivesWe aimed to identify environmental determinants of berry plant distribution and predict how climate change might shift these distributions. MethodsWe used species distribution models to identify characteristics and predict the distribution of suitable habitat under current (2006–2013) and future climate conditions (2081–2100; representative concentration pathways 4.5, 6.0, & 8.5) for five berry plant species:Vaccinium uliginosumL.,Empetrum nigrumL.,Rubus chamaemorusL.,Vaccinium vitis-idaeaL., andViburnum edule(Michx.) Raf.. ResultsElevation, soil characteristics, and January and July temperatures were important drivers of habitat distributions. Future suitable habitat predictions showed net declines in suitable habitat area for all species modeled under almost all future climate scenarios tested. ConclusionsOur work contributes to understanding potential geographic shifts in suitable berry plant habitat with climate change at a landscape scale. Shifting and retracting distributions may alter where communities can harvest, suggesting that access to these resources may become restricted in the future. Our prediction maps may help inform climate adaptation planning as communities anticipate shifting access to harvesting locations. 
    more » « less
  2. IntroductionForecasting range shifts in response to climate change requires accurate species distribution models (SDMs), particularly at the margins of species' ranges. However, most studies producing SDMs rely on sparse species occurrence datasets from herbarium records and public databases, along with random pseudoabsences. While environmental covariates used to fit SDMS are increasingly precise due to satellite data, the availability of species occurrence records is still a large source of bias in model predictions. We developed distribution models for hybridizing sister species of western and eastern Joshua trees (Yucca brevifoliaandY. jaegeriana, respectively), iconic Mojave Desert species that are threatened by climate change and habitat loss. MethodsWe conducted an intensive visual grid search of online satellite imagery for 672,043 0.25 km2grid cells to identify the two species' presences and absences on the landscape with exceptional resolution, and field validated 29,050 cells in 15,001 km of driving. We used the resulting presence/absence data to train SDMs for each Joshua tree species, revealing the contemporary environmental gradients (during the past 40 years) with greatest influence on the current distribution of adult trees. ResultsWhile the environments occupied byY. brevifoliaandY. jaegerianawere similar in total aridity, they differed with respect to seasonal precipitation and temperature ranges, suggesting the two species may have differing responses to climate change. Moreover, the species showed differing potential to occupy each other's geographic ranges: modeled potential habitat forY. jaegerianaextends throughout the range ofY. brevifolia, while potential habitat forY. brevifoliais not well represented within the range ofY. jaegeriana. DiscussionBy reproducing the current range of the Joshua trees with high fidelity, our dataset can serve as a baseline for future research, monitoring, and management of this species, including an increased understanding of dynamics at the trailing and leading margins of the species' ranges and potential for climate refugia. 
    more » « less
  3. ABSTRACT AimThe aim of the current study is to conduct a comprehensive phylogenetic analysis of the genusArbaciato elucidate the evolution and phylogenetic relationships among all extant species and reevaluate the presence of geographic structure within species that have wide, fragmented distributions. LocationSpecimens ofArbaciawere collected from 34 localities spanning the Atlantic and Pacific Oceans, and the Mediterranean Sea. MethodsWe obtained sequences from three mitochondrial markers (COI, 16S and the control region and adjacent tRNAs) and two nuclear markers (28S and 18S; the latter ultimately excluded from the final analyses). Phylogenetic trees were constructed using maximum likelihood and Bayesian inference approaches. A time‐calibrated phylogenetic tree was inferred using a relaxed Bayesian molecular clock and three fossil calibration points. ResultsOur analysis supports the monophyly of the genusArbacia, including the speciesArbacia nigra(previously assigned to the monotypic genusTetrapygus). The new phylogenetic topology suggests an alternative biogeographic scenario of initial divergence between Atlantic and Pacific subclades occurring approximately 9 million years ago. The dispersal and subsequent diversification of the Pacific subclade to the southeast Pacific coincides with the onset of glacial and interglacial cycles in Patagonia. In the Atlantic subclade, the split betweenA. punctulataandA. lixulaoccurred 3.01–6.30 (median 3.74 million years ago), possibly associated with the strengthening of the Gulf Stream current connecting the western and eastern Atlantic. Our study also reveals significant genetic and phylogeographic structures within both Atlantic species, indicating ongoing differentiation processes between populations. Main ConclusionOur study provides valuable insights into the evolutionary history and biogeography of the genusArbaciaand highlights the complex interplay between historical climate changes and oceanic currents in shaping the distribution and diversification of echinoids in the Atlantic and Pacific Oceans. 
    more » « less
  4. Abstract Predicting species' range shifts under future climate is a central goal of conservation ecology. Studying populations within and beyond multiple species' current ranges can help identify whether demographic responses to climate change exhibit directionality, indicative of range shifts, and whether responses are uniform across a suite of species.We quantified the demographic responses of six native perennial prairie species planted within and, for two species, beyond their northern range limits to a 3‐year experimental manipulation of temperature and precipitation at three sites spanning a latitudinal climate gradient in the Pacific Northwest, USA. We estimated population growth rates (λ) using integral projection models and tested for opposing responses to climate in different demographic vital rates (demographic compensation).Where species successfully established reproductive populations, warming negatively affectedλat sites within species' current ranges. Contrarily, warming and drought positively affectedλfor the two species planted beyond their northern range limits. Most species failed to establish a reproductive population at one or more sites within their current ranges, due to extremely low germination and seedling survival. We found little evidence of demographic compensation buffering populations to the climate treatments.Synthesis. These results support predictions across a suite of species that ranges will need to shift with climate change as populations within current ranges become increasingly vulnerable to decline. Species capable of dispersing beyond their leading edges may be more likely to persist, as our evidence suggests that projected changes in climate may benefit such populations. If species are unable to disperse to new habitat on their own, assisted migration may need to be considered to prevent the widespread loss of vulnerable species. 
    more » « less
  5. Abstract AimIntraspecific genetic variation is key for adaptation and survival in changing environments and is known to be influenced by many factors, including population size, dispersal and life‐history traits. We investigated genetic variation within Neotropical amphibian species to provide insights into how natural history traits, phylogenetic relatedness, climatic and geographic characteristics can explain intraspecific genetic diversity. LocationNeotropics. TaxonAmphibians. MethodsWe assembled data sets using open‐access databases for natural history traits, genetic sequences, phylogenetic trees, climatic and geographic data. For each species, we calculated overall nucleotide diversity (π) and tested for isolation by distance (IBD) and isolation by environment (IBE). We then identified predictors ofπ, IBD and IBE using random forest (RF) regression or RF classification. We also fitted phylogenetic generalized linear mixed models (PGLMMs) to predictπ, IBD and IBE. ResultsWe compiled 4052 mitochondrial DNA sequences from 256 amphibian species (230 frogs and 26 salamanders), georeferencing 2477 sequences from 176 species that were not linked to occurrence data. RF regressions and PGLMMs were congruent in identifying range size and precipitation (σ) as the most important predictors ofπ, influencing it positively. RF classification and PGLMMs identified minimum elevation as an important predictor of IBD; most species without IBD tended to occur at higher elevations. Maximum latitude and precipitation (σ) were the best predictors of IBE, and most species without IBE occur at lower latitudes and in areas with more variable precipitation. Main ConclusionsThis study identified predictors of genetic variation in Neotropical amphibians using both machine learning and phylogenetic methods. This approach was valuable to determine which predictors were congruent between methods. We found that species with small ranges or living in zones with less variable precipitation tended to have low genetic diversity. We also showed that Western Mesoamerica, Andes and Atlantic Forest biogeographic units harbour high diversity across many species that should be prioritized for protection. These results could play a key role in the development of conservation strategies for Neotropical amphibians. 
    more » « less