Subterranean Fishes of the World

3888

2016

The Edwards Aquifer in Texas supports abundant stygobiont biodiversity. Extending over 400 km along the Balcones fault zone, the aquifer serves as habitat for >50 described stygobitic species, including four federally endangered species: the Texas blind salamander (Eurycea rathbuni), Austin blind salamander (Eurycea waterlooensis), Peck’s cave amphipod (Stygobromus pecki), and the Comal Springs dryopid beetle (Stygoparnus comalensis). Due to habitat inaccessibility, little is known about the ecology of stygobionts in the Edwards Aquifer, including their life history, population sizes, distributional ranges, trophic dynamics, and interspecific interactions. A flowing artesian well on Texas State University campus has been used to collect and study aquifer organisms for over a century, and it is the type locality for a number of species. Since 2013, the well has been consistently sampled with a 100 μm net for intervals ranging from 24-72 hours with collections ranging from 200 to >1300 individuals per sample. Species collection data was analyzed alongside hydrological data including aquifer discharge and storm events. While there were shifts in species composition after storm events, temporal variance in species richness and abundance were not explained by hydrological fluctuation. Including undescribed stygobion species, sampling efforts have yielded over 30 different species from the artesian well, illustrating the site’s importance as one of the most diverse stygobiont sites known. This occurrence data extends the range of multiple stygobionts in the Edwards Aquifer and prompts discussion of the ecology and biogeography of inconspicuous aquifer fauna.

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23rd International Conference on Subterranean Biology

2016

2016

2016