Flexing Our Mussels
Invasive zebra mussels continue their full-scale assault on native species of freshwater mussels, but northern Michigan’s indigenous clams have found human allies to help them fight back: young scientists at the University of Michigan’s Biological Station on Douglas Lake. This battle holds symbolic weight if the natives are to survive the invasion.
Native to the Caspian Sea and the Ural River of southeast Russia, the zebra mussel uses its strong byssal threads to attach to any hard surface. By latching on to anchors and the bottoms of ships traveling through international waterways, the mussels spread west into Europe and, eventually, across the Atlantic Ocean. Ships entering the St. Lawrence Seaway introduced the invasive species to the Great Lakes in 1988, and zebra mussels have since extended throughout much of North America. The exotics pose a serious ecological threat to the biodiversity of aquatic ecosystems. By reproducing in greater numbers than native species and using them as a substrate, the zebra mussel colonies outcompete the local species of unionid bivalves. The suffocated victims cannot move, gather food, or close their shells to protect from dehydration.
Without help, death is inevitable.
On July 8 I went out with twenty-five others to clean the invasives off four species of clams native to Douglas Lake. In the graveyard of empty shells, a few living natives still resisted their attackers. Each clam we cleaned might reproduce in great numbers, giving the population a meaningful shot at survival. I saved about thirty native mussels; our modest team collectively saved over three hundred. I accidentally killed one, however, when I tried to free her from her living shackles. The shell broke and punctured my skin. The soft, vulnerable tissues inside were now exposed to the world. I finished shucking anyway to provide her with a decent burial.
By Stefanie Trout
What a treat to know the Biological Station is still alive and well. My father, David S. Shetter, B.S. Biology 1932, M.S. 1933, Ph.D. Zoology, 1937, enjoyed many summers there and until recently we had a scrapbook showing the activities and the friends he met there. Unfortunately, the storage space in Florida retirement homes dictates that some things have to be cleaned out. Wish I had known where to send it. This was definitely a seminal experience for a city guy from Cleveland. He loved everthing and had a hard time deciding what to do for his advanced degrees – ichthyology, entymology or herpetology.
Dad subsequently went on to become the director of the Hunt Creek Fisheries Experiment Station in Lewiston from 1943 until his death in 1969. This is now under DNR management. My brother and I grew up at the “Lab”. A wonderful place to learn about the out of doors – many students and scholars coming and going. All summer there were folks camped out on the property observing or collecting. We learned VERY early not to disturb anyone or anything in jars, nets or collecting trays.
There were no data bases established for many things we take for granted today. Hunt Creek has one of the longest data bases in existence for a freshwater trout stream. I certainly hope the current budget crises does not put that in jeopardy.
Call Andy Nuhfer, the current director and have him show you the scrapbook I did on the history of Hunt Creek last year. I think you could do a good article on that and what the Lovells Historical Society is doing for the fishing lodges on the North Branch and the Main Stream. All of this was tied together in the beginning.
Keep up the good work!
Alice Shetter Hoelzer-Hawthorne
3808 Doune Way
Clermont, FL 34711