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Understanding the influence of spatiotemporal variation in environmental factors on phenology is crucial for determining the effects of climate change on amphibian populations. Here we quantify the relative influence of temperature and precipitation on surface activity of a terrestrial salamander, the Eastern Red-Backed Salamander (Plethodon cinereus) in Richmond, Virginia, USA. Specifically, we used spatial capture recapture methods to test the influence of different metrics for temperature and precipitation on baseline detection probability. We found that soil temperature, particularly at 30 cm below the surface, is a better predictor of detection than air temperature or cumulative precipitation; however, greater cumulative precipitation resulted in a higher detection probability. We also show that a quadratic effect was favored in all scenarios suggesting this species has an optimal soil temperature and cumulative precipitation for surface activity during a particular year. The highest detection probability was associated with 12.6º C at 30-cm below the surface and 0.75 cm of cumulative precipitation during the 2-d period prior to the survey occasion. In addition to contributing knowledge on the specific environmental metrics that best predict surface activity for P. cinereus, this work illustrates the importance of incorporating soil temperature measurements in capture mark-recapture studies of terrestrial salamanders. For projects with limited resources, our work indicates which fine-scale environmental measurements associated with terrestrial salamander activity in the southern portion of the range are best.
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Range-wide salamander densities reveal a key component of terrestrial vertebrate biomass in eastern North American forests
Characterizing the population density of species is a central interest in ecology. Eastern North America is the global hotspot for biodiversity of plethodontid salamanders, an inconspicuous component of terrestrial vertebrate communities, and among the most widespread is the eastern red-backed salamander,Plethodon cinereus. Previous work suggests population densities are high with significant geographic variation, but comparisons among locations are challenged by lack of standardization of methods and failure to accommodate imperfect detection. We present results from a large-scale research network that accounts for detection uncertainty using systematic survey protocols and robust statistical models. We analysed mark–recapture data from 18 study areas across much of the species range. Estimated salamander densities ranged from 1950 to 34 300 salamanders ha−1, with a median of 9965 salamanders ha−1. We compared these results to previous estimates forP. cinereusand other abundant terrestrial vertebrates. We demonstrate that overall the biomass ofP. cinereus, a secondary consumer, is of similar or greater magnitude to widespread primary consumers such as white-tailed deer (Odocoileus virginianus) andPeromyscusmice, and two to three orders of magnitude greater than common secondary consumer species. Our results add empirical evidence thatP. cinereus, and amphibians in general, are an outsized component of terrestrial vertebrate communities in temperate ecosystems.
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- Award ID(s):
- 2224545
- PAR ID:
- 10573325
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Royal Society
- Date Published:
- Journal Name:
- Biology Letters
- Volume:
- 20
- Issue:
- 8
- ISSN:
- 1744-9561
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rsbl.2024.0033
