The overall goal of this project was to assess the use of eDNA methods to monitor amphibians in Alberta wetlands and potentially augment current ABMI sampling. During the project we completed several steps related to developing an eDNA approach to monitor amphibians. These included the following:
Develop primers for target Alberta amphibian species,
Test primer sets on tissue samples to ensure they are specific to target species,
Collect samples from multiple wetlands and analyze, and
Compare results to data collected using ARUs.
eDNA refers to a collection of technologies and methodologies used to detect species based on DNA fragments in relatively small environmental samples. Because the technique can detect species without having to actually collect specimens, it is well-suited to detecting rare and elusive species, and all lifestages of a species with distinctly different developmental phases (e.g., egg, larval, adult).
Autonomous Recording Units (ARUs) are audio recording devices that can be programmed to sample at scheduled times throughout the day. The ABMI currently uses ARUs to monitor amphibians across Alberta. The dominant audio signals from amphibians are breeding calls in early spring; these calls are generally considered an indication of the abundance of breeding adults (Nelson and Graves 2004, Corn
et al. 2011) but not necessarily of successful breeding.
The eDNA approach detected three amphibian species across the four sites sampled in this project. Blotched Tiger Salamander was detected at two sites, Wood Frog was detected at every site, and Boreal Chorus Frog was detected at one site. Northern Leopard Frog, Canadian Toad, and Western Toad were not detected at any of the sampling sites.
Three amphibian species were identified by ARU methods at the four sites. Boreal Chorus Frog and Wood Frog were detected at all sites and a single Western Toad was detected at one site.