Understanding the clonal and population genetic structure of the freshwater bryozoan Fredericella sultana is essential for understanding the epidemiology and management of the myxozoan parasite Tetracapsuloides bryosalmonae that causes the Proliferative Kidney Disease (PKD) in wild and farmed salmonids. Common, widespread and susceptible F. sultana clones can serve as a persistent parasite reservoir, supplying disease epidemics in fish, yet, at present, no information of the clonal structure of F. sultana populations exists. To predict the impact of environmental change on spread of PKD in fish, it would be essential to resolve questions regarding geographic distribution of susceptible and resistant F. sultana genotypes, and their potential response to environmental change. At present such information is not available due to lack of neutral genetic markers for F. sultana. This 15 month fellowship proposal will (i) develop the required nuclear genetic markers that will allow high resolution genetic studies of the clonal and population genetic structure of F. sultana populations, and (ii) use these markers in the first genetic surveys of F. sultana populations that are either known to carry the disease or known to be healthy, based on earlier ecological surveys. Results of the study will be highly beneficial for preventive and predictive applications to manage PKD in salmonids.