The presence of Cladophora in the Great Lakes, including phosphorus-rich Lake Erie, is an age-old problem that has found its way back onto the radar of scientists, including Mercyhurst University biologist Steven Mauro, Ph.D.
Reports of beach fouling, concerns that incidences of avian botulism are linked to Cladophora and scientific studies linking Cladophora and human pathogens have sparked renewed attention in the nuisance algae.
For Mauro, whose research in recent years has focused on potential human pathogens in the recreational waters of Lake Erie at Presque Isle State Park, a new grant will enable him to look more closely at Cladophora. Mauro is the recipient of a $21,000 award from Pennsylvania Sea Grant to study the role temperature and phosphorus have on the survival of bacteria on algae in the Great Lakes.
"Accumulation of algae in lakes and oceans can be problematic because of its ability to harbor bacteria," Mauro said. "Specifically, algal mats of Cladophora in the Great Lakes harbor very high concentrations of bacteria, some of which are pathogenic to humans."
The growth of Cladophora is intimately linked to temperature conditions and the availability of phosphorus and, yet, Mauro said scientists know very little about how these same factors influence bacterial abundance and growth on Cladophora, information that is vital to assessing those factors that make the presence of Cladophora harmful to humans.
Mercyhurst researchers will test how temperature and phosphorus concentrations impact bacterial concentration on Cladophora under controlled laboratory conditions, findings that will be directly examined in Presque Isle beach waters in summer 2013.
"Together, this information will lead to a better understanding of how global warming and persistent phosphorus loading into waters contribute to the accumulation of bacterial pathogens in recreational waters," he said.
Since 2006, Mauro and his team of student researchers have developed protocols to reduce bacterial sampling time, produced scientific evidence linking human waste from creeks to beach water contamination and established the first long-term human bacterial pathogen-specific study at Presque Isle.