Biological response signature of oil brine threats, sediment contaminants, and crayfish assemblages in an Indiana watershed, USA.

The Patoka River watershed contains a divergent landscape of oil and gas exploration, intensive agriculture, and surface mining mixed with National Forest, Wildlife Refuges, and a large recreational reservoir. We evaluated species diversity among different land uses, including, commercial, forested, residential, and agriculture, and determined relationships among disturbance scale, habitat requirements, contaminants, and patterns in species distributions. Primary burrowing species, Cambarus polychromatus, Cambarus cf diogenes (Lacunicambarus A), and Fallicambarus fodiens, were tolerant of higher concentrations of contaminants than aquatic tertiary burrowing species. Cambarus polychromatus was among the last species of crayfish at the most disturbed sites, while it was absent from pasture and agricultural landscapes that allowed cattle access along banks. Four species of Orconectes were found in the reference and agricultural landscapes within the watershed, including O. immunis, O. indianensis, O. inermis inermis, and O. propinquus. Orconectes indianensis distribution was determined by the presence of rock habitat and absence of contaminants. No Orconectes species were found in acid mine leachate-affected streams with high levels of molybdenum. Cambarus laevis was found in the highest-quality reference areas, which were associated with karst habitats and no contaminants. Burrowing crayfish species were associated with the oil derricks in the lower and middle watershed, which contained increased concentrations of strontium, phosphorus, and various organic parameters associated with oil brine PAHs.