Examining Threats to Cryptic Cave Salamanders in Central Texas to Petition for their Protection

• Main Authors: Kuczek, Aurora, White, Annabelle
• Other Authors: Cagle, Nicolette
• Format: Master Thesis
• Language: English
• Published: 2023
• Subjects: Endangered salamanders; Karst; Texas Hill Country; Eurycea; Edwards-Trinity Aquifer; Stygobites; Carbonic acid
• Online Access: https://hdl.handle.net/10161/27166

Background and Context. The Edwards-Trinity aquifer system in Texas Hill Country is one of the most biodiverse ecosystems in the world. Made of karst that was formed by tectonic plates millions of years ago when Hill Country was submerged by an ocean, this region is geologically unique and characterized by its underwater caves and aboveground springs formed when limestone rocks are dissolved by carbonic acid when it interacts with water. This karstic region provides habitat to stygobites, or species that are restricted to life in caves, and have very limited ranges due to high isolation and extreme endemism. With 60 species of invertebrates identified alone in the Edwards aquifer in 2019, there are also species of benthic blind fish, bacteria, and a genus of plethodontid or lungless salamanders–Eurycea. Eurycea Conservation. Coordinates are known for 14 species of Eurycea salamanders in Texas Hill Country that are adapted to aquatic life. Most are state and/or federally endangered or threatened due to high sensitivity of anthropogenic activities like habitat destruction. Of the 14 species we analyzed, there are three species of undescribed salamanders whose life histories are uncertain, given the inaccessibility of many Eurycea habitats as well as complicated genetic lineages and unreliable morphologies. Our client, Save Our Springs (SOS) Alliance, a central Texas nonprofit dedicated to protecting these karstic ecosystems and the species that inhabit them, is in the process of petitioning to the U.S. Fish and Wildlife Service (USFWS) for the protection of the Pedernales River Springs salamander. SOS Alliance aims to petition for the protection of additional Eurycea species under the same premises. Significance and Objectives. Our main objective is to find which salamanders should be most prioritized by our client to petition for federal protection based on our analyses. Our sub-objectives are to find which environmental variables are posing the most threat to Eurycea spp. and to suggest several management ...