Principal Investigator: 
Matthew Shank (
Susquehanna River Basin Commission
Didymosphenia geminata (didymo) is a benthic freshwater diatom capable of producing nuisance blooms that impact the recreational, ecological, and aesthetic value of freshwater ecosystems. Recently, didymo has expanded its range and ecological tolerances leading to massive blooms in areas where it was previously undocumented or had existed in low abundance. Since 2007, these blooms have been increasingly observed in Pennsylvania, yet currently no inventory of its distribution or assessment of watershed vulnerability exists for the state. The intent of this study was to conduct a comprehensive assessment of didymo throughout PA and provide relevant technical information that could help inform management efforts. This study addresses three important research questions regarding didymo in PA streams: 1) what is the current and historic distribution of didymo in Pennsylvania; 2) what is the potential habitat suitability for nuisance didymo blooms in Pennsylvania; and 3) How does didymo presence affect the nutritional content of biofilms.    
Research Year: 
Funding Amount: 
Current or Past research?: 
Past Research

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