Zebra mussel research finishes first field season
MAISRC researcher Dr. Michael McCartney spent the summer and fall of 2014 collecting samples to support three major areas of zebra mussel research.
First, McCartney collected adult zebra mussel tissues from twelve lakes and three river systems throughout Minnesota. McCartney and his team ensured that collections occurred in all major regions of infestation in the state. Working in conjunction with the University of Minnesota Genomics Center, these tissues will be studied to help identify source populations and the pathways of spread of zebra mussels.
Second, the team collected veligers (microscopic larvae) from multiple locations within ten lakes to help develop molecular methods for early detection. Now, the arduous process (pictured) of counting veligers and preparing them for quantitative molecular testing begins. The samples gathered throughout the summer are very valuable for many reasons: the sheer number of samples, the variation among the lakes sampled with respect to both lake chemistry and plankton communities, and the time period covered by these collections (samples were taken during each month of the reproductive season).
Third, McCartney studied how zebra mussels spread downstream in small rivers. The initial indication is that settlements of juvenile mussels on the stream bottom drops to near zero just a short distance downstream from the source lake. Currently, his lab is counting veliger larvae from samples along these same rivers to examine whether numbers of larvae also decline downstream. In summer 2015, this work will continue on other river systems. All of the results will be used to estimate how many veligers can travel downstream, and how far they can go. These results may help DNR refine the way they designate infested, interconnected waterways.
Looking forward, McCartney’s zebra mussel research will focus on understanding pathways of spread to help target prevention efforts as wisely as possible toward lakes with the highest risk of future invasions. This research will be coupled with the development of a rapid water test to detect the presence of veligers, which when contained, may be able to control an infestation before it becomes problematic. Dr. McCartney believes this will become increasingly important as treatment options (e.g. Zequanox and potash) are being explored. Thank you to the Gull Chain of Lakes Association for their support of this research.