Part of a series of articles titled Amphibian Monitoring in the National Capital Region.
Previous: Prince William Amphibian Monitoring 2023
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We monitor wetlands and streams at Rock Creek Park. Field teams visit wetlands and streams, recording which amphibian species they observe and in which sites. Looking across all sites in a park, they generate a measure of species “occupancy,” that shows what proportion of sites are occupied by a particular species.
We want to know, “is there a change in occupancy over time?”
A few amphibian species are found outside of the wetland and stream environments that we monitor (like terrestrial, red-backed salamanders and burrowing, eastern spadefoot toads). These species may live in the park, but our monitoring is not designed to document them. While we do record incidental sightings, they are excluded from the data analysis.
In 2023, we observed four wetland species. Since amphibian monitoring began in Rock Creek in 2005, a total of nine wetland species have been observed (see Figure 1). Lower numbers in 2023 are the result of fewer visits to monitoring sites. Usually there are two each year. Field crews visited 13 wetlands, adding three new sites this year. All sites were visited once in March of 2023.
Wood frogs were the most abundant amphibian detected (750 larvae), followed by American bullfrogs and northern green frogs. Each species was observed at one wetland.
See below for how to read this figure!
Stream sites were not visited in 2023. In 2022, the last year of monitoring, we observed two salamander species: northern dusky salamanders and northern two-lined salamanders. The northern two-lined salamander was the most abundant species observed (five adults, four juveniles, and 57 larvae), and was observed at the most sites.
Part of a series of articles titled Amphibian Monitoring in the National Capital Region.
Previous: Prince William Amphibian Monitoring 2023
Last updated: March 18, 2024