Making a mussel isn’t easy. After eggs are fertilized from an upstream male, the female mussel lures a host and sprays her larvae onto the fish. Most species of mussel use a specific type of host fish. The larval mussels incubate on the host for a few days and then drop off as a juvenile mussel to find suitable habitat for growth and survival. The juvenile mussel may take 1 to 4 years to reach the adult stage and then may live for several decades.
At the Center for Mollusk Conservation in Frankfort, Aquatic Scientist and Malacologist Monte McGregor aims to increase reproduction odds for mussels by matching females with host fish in the laboratory before releasing juveniles into the wild. With each year in operation, the Center’s scientists learn more about what juvenile mussels eat, what host fish works best and how to artificially propagate mussels by skipping the fish host stage in an incubated petri-dish.
During 2011, the Conservancy sought out McGregor’s assistance before acquiring the West Tract, a 78-acre property with 1,100 feet of accessible frontage along the Green River.
“We wanted to know more about the property’s biodiversity – especially the mussels known to inhabit this part of the Bluegrass State,” says Jeff Sole, Director of Conservation Programs for The Nature Conservancy of Kentucky. “Monte and his team came to the West Tract and surveyed a mussel bed associated with the property’s river frontage.”
McGregor’s survey revealed 28 mussel species in the bed, including one federally-endangered species and at least 3-4 other globally-imperiled species. While remarkable, this wasn’t news to McGregor.
“The Green River harbors a diverse and significant array of mussels, more than half of the mussels found in the state and about 20 percent of what we have in the country,” says McGregor.
With a lifespan of up to 50 years, mussels spend most of their time in one spot, filtering bacteria and low levels of pollution from waters that flow around them. This also makes them vulnerable to chemicals, sediment and changes in temperature. As a result, freshwater mussels serve as strong indicators of water quality.
“The ongoing sampling and survey work Monte and his team conduct in places like the Green River provides some of the best data we get for monitoring how mussel populations respond to our work,” adds Sole. “We wouldn’t be able to accomplish our goals there without him.”