Sci-Comm: Holt Research Forest Salamander Counts and Measurements

Did you know that salamanders act as critical indicators for the health of an ecosystem? Their moist, permeable, and sensitive skin makes them susceptible to fertilizers, other chemical imbalances on the forest floor, and drought. Thus, we began measuring and counting the salamanders in 1983. Periodically during the field season, when conditions were ideal (usually after a rainy period), the field crew surveyed man-made salamander habitats to assess the population. 

Red-backed Salamander at the Holt Research Forest.

The field methods used to conduct these salamander counts drastically changed since the surveys began. Initially, rainy night censusing was conducted, but later dropped because it did not provide sufficient data and was rough on crew morale. It was also hard to gather the crew quickly when the field conditions were moist enough. Quadrat searches were also initially used but were labor-intensive and weather-dependent. Quadrat searches are also destructive in an area where disturbance should be limited. Because of this, in 1987, we switched to the shingle method, which provides a non-destructive sample from a consistent location. 

So, what is the shingle method? Cedar shingles on the forest floor act as a refuge for salamanders. Within the study grid, we set out shingles along two transect lines in locations covering a range of habitat types in stations of six. Exactly as it sounds, shingles are the materials used on your house to create habitats for salamanders. Each shingle was turned over individually to collect the data, and any salamander found was placed in a resealable bag moistened with water. The following were recorded for each salamander: color phase, snout vent length, and sex. Then, the salamander was returned to the shingle under which it was found. Unfortunately, salamander counts and measurements were stopped due to ethical concerns. The handling of salamander populations by researchers could have led to the spread of Chytridiomycosis, a disease caused by a fungal pathogen that is deadly to the species.

Cedar shingle at a salamander collection station.

Four Salamander Counts and Measurements datasets are available for download as CSV files at the HRF data archive on the Forest Ecosystem Monitoring Cooperative (FEMC) website (https://www.uvm.edu/femc/data/archive/project/salamanders), along with an additional dataset available upon request. Please refer to the table below for more information about each dataset, and visit the Holt Research Forest data archive to learn more about our publicly available datasets and their metadata!

Table 1. Salamander datasets at the Holt Research Forest data archive.

Dataset Name	Description	Data Availability
Salamander Counts 1m2	Counts only (no measurements) of salamanders found in random 1m2 plots in each block of the study area; 1983-86, 1991, 1995.	Yes
Salamander Night Counts	Salamander census in random plots on rainy nights.	Yes
Salamander Shingle All Years	Survey of redback salamanders under artificial cover boards; 1987-2012.	Yes
Salamanders, 1m2 1995	Measurements of salamanders in 1m2 search plots, in the same format as the shingle survey; 1995.	Yes
Salamander Scanned Data	Salamander counts and tree inventory within the Holt Research Forest, including quadrat searches, shingle counts, strip censusing, moisture block readings, percent coverage, data about trees, logs, and stumps, and a document on sexing techniques for red-back salamanders.	By Request