Characterizing Wetland Hydrology, Chemistry, And Soils For An Endemic Crayfish, The Piedmont Blue Burrower
Anthropogenic alteration of Earth's ecosystems has pushed global biodiversity into a state of crisis. Freshwater species have been particularly vulnerable, with crayfish ranking as the second most imperiled taxonomic group in North America. Primary burrowers represent only 15% of crayfish species in North America; however, they constitute 32% of imperiled crayfish. Despite their conservation importance, little is known about the ecology of burrowing crayfish. To advance our knowledge about the habitat characteristics of burrowing crayfish, groundwater hydrology, water chemistry, and soil properties were assessed to determine their importance for the state-listed endangered, primary burrower Cambarns harti. Groundwater hydrology and chemistry were monitored from shallow wells installed among C. harti burrows and in similar areas without burrows (< 50 m away) at 4 sites across Meriwether County (GA). Groundwater depth and temperature were automatically recorded every 30 min, whereas dissolved oxygen and pH were measured manually every 1-4 weeks from 6/6/2013-8/1/2014. Water chemistry (K+ , Mn2+/3+ , Cl", Fe2+/3+ , Si02) was analyzed from samples every 1-4 weeks (1/16/2014-8/1/2014) from wells and crayfish burrows. To assess crayfish soil preferences, 3 soil cores were collected from random locations within 10 m of each well. Groundwater levels for areas with C. harti burrows were ~ 3 times shallower than areas lacking burrows. Groundwater was acidic (pH=5.60, mean) and experienced hypoxia (< 3 mg/L dissolved oxygen) for at least 48% of the study. Wells and burrows had similar water chemistry except for Cl", which was on average 16- 18 times more concentrated in burrow water. Soils were sandy (85.5%) with minor amounts of silt/clay (11.3%) and only differed slightly among sites. Thus, this study found that C. harti inhabits wetlands with shallow groundwater (> 1 m) that are acidic and often hypoxic. While this burrower can tolerate variation in groundwater level, anthropogenic activities that depress groundwater could extirpate populations of C. harti.
North America, Cambarus Harti., Meriwether County (GA), Crayfish, Groundwater, Environmental Indicators and Impact Assessment, Environmental Studies
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