Amphibian Monitoring at Antietam National Battlefield, 2023

Antietam National Battlefield is home to at least five amphibian species, and its wetlands are monitored for them. The Park Service monitors amphibians in the National Capital Region by recording which species are found at which sites; across all sites, that gives each species' occupancy — the share of sites where it is present — and the question is whether occupancy is changing over time.

Some amphibians live away from the wetlands being monitored — land-dwelling red-backed salamanders, for instance, or burrowing eastern spadefoot toads. They may live in the park, but the monitoring is not designed to find them, and chance sightings are noted but left out of the analysis.

An American toad (Anaxyrus americanus). NPS / C. Shafer.

Wetlands in 2023

Crews visited seven wetlands once, in May 2023; usually there are two visits a year, which is why the 2023 numbers are lower. Two of the nine wetland sites mapped earlier were dropped from the list because they lie outside the park boundary. Two wetland species were found. American toads were the most plentiful, with roughly 30,000 tadpoles, and each species was found at just one wetland.

Since monitoring at Antietam began in 2021, five wetland species have been seen:

• American toad;
• Fowler's toad;
• northern green frog;
• pickerel frog;
• northern dusky salamander.

Graphs of occupancy will follow once there are a few years of repeat visits.

Corrected: the NPS article lists an "American Fowler's toad"; the species is Fowler's toad.

The data were preliminary or provisional and subject to revision, and had not received final approval from the U.S. Geological Survey.

Sources

• National Park Service, National Capital Region, "Antietam Amphibian Monitoring 2023," in the series Amphibian Monitoring in the National Capital Region. https://www.nps.gov/articles/000/antietam-amphibian-monitoring-2023.htm