Early detection tool developed for invasive mussels and their larvae
MAISRC scientists have developed a new assay that can detect invasive mussels and their microscopic larvae, and distinguish between zebra and quagga mussels in the same sample – even when their numbers are very low, such as in samples from newly infested lakes.
Dr. Mike McCartney, Dr. Jessica Eichmiller, and student Sendréa Best collaborated on development of this early detection tool. Early detection is critical because it provides a better chance for early intervention which may prevent the establishment of a nascent infestation.
To test for the presence of invasive mussels, this method is being applied to samples from plankton tows – a common method in which a fine mesh net is pulled through the water to collect microscopic organisms. The samples are analyzed using a quantitative PCR (qPCR) instrument. After only a few hours, this new assay will reveal whether zebra or quagga mussels are present, as well as estimate their abundance.
Until now, the industry standard for early detection required viewing samples of water using cross-polarized light microscopy, which is effective but very time-consuming. There had been no method for distinguishing zebra from quagga mussel veligers, which have a very similar size and shape. MAISRC researchers are now pursuing this molecular approach which appears to be a promising alternative: not only does it discriminate between zebra and quagga mussel DNA, but it is much easier to efficiently analyze multiple samples at once.
Quagga mussel populations have exploded in the lower Great Lakes, replacing zebra mussels. It’s crucial that Minnesota has an early detection method like this that can be readily applied to lake, river, and stream samples.
Going forward, researchers will further refine the assay by conducting Limit of Detection trials, which account for other factors that could influence results such as non-target planktonic organisms, detritus, and dissolved contaminants.
Learn more about MAISRC research on zebra mussels here.