3.5.1.7 Amphibians

Non-Seminoe Reservoir Aquatic Features

As described above in Section 3.4, Black Canyon performed an Aquatic Resources Delineation to assess the nature and degree of the Project’s potential impacts on areas potentially subject to the jurisdiction of USACE under Section 404 of the CWA. Based on the results of the study, several aquatic resources were identified in the Project vicinity, including 13 freshwater emergent wetlands, 11 ephemeral streams, three intermittent streams, and five perennial streams, most of which occur along the proposed transmission line corridor and access roads. Most of these features are located at a high elevation often in steep terrain and have few, if any, associated fish or aquatic biota. Most of these aquatic resources are considered low-quality due to the lack of persistent year-round stream flow, relatively high-water temperatures, and limited riparian vegetation (HDR 2022f). Limited information is available describing the fisheries and aquatic resources of these tributary features.

The complete methods and results of the Section 404 Preliminary Jurisdictional Determination Study are presented in the Aquatic Resources Delineation Report (HDR 2022f) (included as Appendix B).

3.5.1.7 Amphibians

Amphibian species in Seminoe Reservoir and within the Project vicinity are not welldocumented. Many of the aquatic habitats (e.g., ephemeral and intermittent streams) may or may not contain aquatic life, which is largely dependent on the frequency and duration that surface water is present.

Though not often observed, at least six species of amphibians are native to the region.

Amphibian habitat preferences are primarily influenced by food and reproductive requirements. Species that may be found in the Project vicinity may include Northern Leopard Frog (Lithobates pipiens), tiger salamanders (Ambystoma mavortium), boreal chorus frogs (Pseudacris maculata), and Plains spadefoot (Spea bombifrons) in the Shirley Basin (Orabona et al. 2016, BLM 2008b). The Boreal Toad (Anaxyrus boreas), Columbia Spotted Frog (Rana luteiventris), and Great Basin Spadefoot (Spea intermontane) are unlikely to occur in the Project vicinity.

The Columbia Spotted Frog, Great Basin Spadefoot, and Northern Leopard Frog are listed as Wyoming BLM Sensitive Species and WGFD SGCN Tier II species. The Boreal Toad is also listed as a Wyoming BLM Sensitive Species but is a WGFD SGCN Tier I species. None of these species were observed during the 2021 Habitat Assessment and Rare, Threatened, and Endangered Species Evaluation Study (HDR 2022c) (Appendix G). Based on range and habitat data analyzed as part of the 2021 Habitat Assessment and Rare, Threatened, and Endangered Species Evaluation Study (HDR 2022c), the Boreal Toad, Columbia Spotted Frog, and Great Basin Spadefoot do not occur in the Project vicinity. However, because the Northern Leopard Frog is a widespread species, relatively common in Wyoming, and occurs in a broad range of aquatic environments, it is likely present in the Project vicinity (HDR 2022c).