A new study, “Range-wide salamander densities reveal a key component of terrestrial vertebrate biomass in eastern North American forests”, (paywall) published in the August 2024 issue of Biology Letters describes the significant ecological role of the eastern red-backed salamander (Plethodon cinereus) in forests across eastern North America.

For findings reported in “Range-wide salamander densities” researchers applied statistical modeling, systematic survey protocols and mark-recapture techniques, across 18 study areas to analyze data. This approach allowed the team to overcome longstanding issues in estimating population densities, providing a clearer picture of the species’ role in terrestrial ecosystems.

The authors estimate salamander densities ranging from 1,950 to 34,300 individuals per hectare, with a median density of 9,965 per hectare. To put this in perspective, the higher end of these estimates means that in some areas, there are more than three salamanders for every square meter of forest.

Even at the lower end, salamander densities are comparable to, or exceed, populations of more visible species. According to the authors, “the biomass of P. cinereus is two to three orders of magnitude greater than that of other common secondary consumers,” including birds and small mammals.

A secondary consumer is an organism that primarily feeds on other animals (in this case, invertebrates like insects), playing a key role in transferring energy through the food web.

The study contributes to long-term research showing how salamanders, as one of these secondary consumers, contribute significantly to the biomass of vertebrate communities in temperate forests and help maintain balance within their ecosystems.

Hubbard Brooker Kerry Yurewicz, based at Plymouth State University, contributed to “Range-wide salamander densities reveal a key component of terrestrial vertebrate biomass in eastern North American forests” and regularly uses salamander data collected in the Hubbard Brook Experimental Forest as a part of her ongoing work to better understand how these animals are adapting to rapid climate change in New England.

“Range-wide salamander densities reveal a key component of terrestrial vertebrate biomass in eastern North American forests”

DOI: https://doi.org/10.1098/rsbl.2024.0033

Authors:
Evan H. Campbell Grant
Jillian Fleming
Elizabeth Bastiaans
Adrianne B. Brand
Jacey L. Brooks
Catherine Devlin
Kristen Epp
Matt Evans
M. Caitlin Fisher-Reid
Brian Gratwicke
Kristine L. Grayson
Natalie T. Haydt
Raisa Hernández-Pacheco
Daniel J. Hocking
Amanda Hyde
Michael Losito
Maisie G. MacKnight
Tanya J. H. Matlaga
Louise Mead
David Muñoz
William Peterman
Veronica Puza
Charles Shafer
Sean C. Sterrett
Chris Sutherland
Lily M. Thompson
Alexa R. Warwick
Alexander D. Wright
Kerry Yurewicz
David A. W. Miller