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Date of Award


Document Type

Thesis-ISU Access Only

Degree Name

Master of Science (MS)


School of Biological Sciences

First Advisor

Robert L. Preston


Orconectes rusticus, the rusty crayfish, is a species native to the Ohio River Basin in the United States. Through human-aided introductions it has successfully invaded freshwater environments in multiple states, including several East Coast states. Preliminary studies showed that O. rusticus can survive in seawater for up to nine days (unpublished data). In this study, we looked at the rates of survival of O. rusticus in different salinities. We also investigated the methods by which O. rusticus is able to tolerate salinity increases, including hemolymph osmotic pressure, free amino acid accumulation in tissues and fluids, and accumulation of sodium and chloride ions in hemolymph. We found that Orconectes rusticus responds to increases in salinity in a manner similar to that of euryhaline decapod crustaceans, suggesting it might be capable of living in a variety of salinity environments, including East Coast estuary ecosystems. The ability of O. rusticus to tolerate a wide range of salinities is of ecological significance because this species of crayfish can cause significant environmental changes in new habitats where it becomes established.


Imported from ProQuest Bazer_ilstu_0092N_10213.pdf


Page Count


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