Field Notes
U.S. Fish & Wildlife Service
Field Notes Entry   
Mussel Discovery on the Gasconade
Midwest Region, July 30, 2007
Print Friendly Version

There is an intimate relationship between freshwater mussels and fish that science is just beginning to comprehend.  Within the past decade malacology, the study of freshwater mollusks, made significant advances in unraveling the natural processes of these intriguing creatures. 

In Missouri, Andy Roberts, malacologist for Ecological Services, works tirelessly in cooperation with Dr. Chris Barnhart of Missouri State University and other mussel biologists with the Missouri Department of Conservation.

Freshwater mollusks are the most threatened creatures in North America and possibly the world.  This is no different in the Midwest.  Roberts’ job entails a variety of issues related to habitat conservation for mussels.  More often than not, these efforts benefit fish as well.  Over the years science has discovered many of these mussels have specific fish hosts they depend on for reproduction and survival.  A healthy fish population is imperative to the existence of healthy mussels. 

A decline in fish species or a change in physical habitat could easily destroy mussel beds which may be hundreds of years old. 

Recently, a gravel mining operation had requested to increase their tonnage production of gravel.  In order to do this they would need to comply with environmental regulations; thus Roberts and Ecological Services involvement.  Unfortunately Roberts had a recent malfunction with his jet boat and was unable to conduct the survey. 

Although the water was a little bit high Roberts was able to determine the bar was too unstable and newly formed to be habitat for mussels.  An outside bend above the bar is actively eroding due to loss of a riparian corridor and depositing materials too quickly to allow for the establishment of mussels. 

After discovering this, Roberts suggested exploring upstream.  Approximately 11 miles upstream of the confluence, where big river influence meets with Ozark stream characteristics, the team hit paydirt.  Within 5 minutes of wading around a stable bar, Roberts found the half shell of a pink mucket, a federally endangered mussel.  The crew donned snorkeling gear and began to seek out more. 

Within a half hour they had collected 21 species of mussels from an area half the size of a skating rink.  They included rare species like elktoe, spectaclecase, black sandshell and individual mussels that were almost older than Andy’s age and mine combined. 

Contact Info: Larry Dean, 612-713-5312, Larry_Dean@fws.gov
Find a Field Notes Entry

Search by keyword

Search by State

Search by Region

US Fish and Wildlife Service footer