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E-M:/ mussel survey, Bean Creek Watershed

FOR IMMEDIATE RELEASE:                      August 28, 2004
                                                                        Janet Kauffman, ECCSCM coordinator, 517-448-4973
                                                                        Peter Badra, aquatic zoologist, Michigan Natural Features Inventory,
                                                                                                                                      517- 241-4179
                                                                        MNFI website: http://web4.msue.msu.edu/mnfi/home.cfm

Native mussels of “special concern”
found in Bean Creek Watershed

       17 different species of freshwater mussels, including 4 rare species of special concern in Michigan, have been identified in Bean Creek Watershed in Lenawee and Hillsdale Counties.   
       A survey of freshwater mussels (clams) was conducted in July and August by aquatic zoologists from the Michigan Natural Features Inventory (MNFI), a program of Michigan State University.
       MNFI staff surveyed 9 sites in Bean Creek and three tributaries.  Two excellent sites, one in St. Joseph Creek, a tributary northwest of Hudson, and the other in lower Bean Creek near Morenci, were habitat for many species, with dozens of individual mussels found alive.  
       Freshwater mussels are among the most endangered organisms in North America. Unlike fish, they can’t swim away if sediment or pollutants threaten the stream habitat.
Rare species
       The four mussel species of special concern – slippershell, cylindrical papershell, round pigtoe, and rainbow mussel – were found only in St. Joseph Creek. That tributary was also recently listed as an excellent quality cold water stream by a Michigan Department of Environmental Quality bio-survey.
       In Michigan, “special concern” is a designation for rarely-found species needing special protection before they reach dangerously low population levels.  According to the Michigan Natural Features Inventory, if these species continue to decline, they would be recommended for Threatened or Endangered status.
Poorer sites
       Poorer sites were documented in the middle Bean Creek in Medina Twp, and Lime Creek in Medina Twp, where only a few live clams were found.  Two tributaries, which were recently listed as “impaired” because of nutrients and manure discharges, feed into middle Bean Creek and into Lime Creek.  
       The worst sites were in Silver Creek near Morenci, where no live mussels were found.  Silver Creek, in a heavily drained agricultural area, had silt more than 6 inches deep in some stretches.  Recent drainwork upstream had removed vegetation and scoured streambanks.  Because clams can’t move away, they often suffocate under heavy deposits of silt.
       “The good news is, some parts of the Bean watershed are in excellent shape,” said Janet Kauffman, of Environmentally Concerned Citizens of South Central Michigan.  “The bad news is, some streams have very little life left in them.  We need to protect what we’ve got and restore what we’ve lost.”  
       Mussels have complex life cycles -- they need fish to reproduce.  Young larval clams hitch rides on fish and then drop off at new sites to grow.  “Where you’ve got clams, you’ve got fish,” said Kauffman.  “We need to protect these important stream habitats.”
       The Michigan Natural Features Inventory survey was funded by a grant from the Water Sentinels fund of Sierra Club and coordinated by volunteers with Environmentally Concerned Citizens of South Central Michigan.

For more information on the survey, photos of mussels, see http://www.eccscm.org