Culturing the Sheepnose Mussel
BY JORGE BUENING, GENOA NFH
The sheepnose is a federally endangered freshwater mussel that Genoa National Fish Hatchery (NFH) is working to propagate. While uncommon in the rest of its range in the Upper Mississippi River Basin; the sheepnose is fairly common in the lower Chippewa River. It is a conglutinate producer, which means that it produces packets that look like food particles to potential host fish. When the fish eat the particle they become infested and will potentially produce juvenile sheepnose.
The sheepnose is an interesting creature that offers some challenges to captive propagation. The first of these challenges is that their brooding window is very small. This is the time when the glochidia, which are baby mussels before they attach to a host fish, are available to infest host fish. In other mussels, this brooding period can last for several months. In the case of the sheepnose it lasts just over a week, generally around the Fourth of July. Another challenge is that the host fish the sheepnose uses is the golden shiner. This is a species that is not readily available at Genoa NFH right now. Until we have established a broodline at the hatchery, we are limited by the small numbers of golden shiners that we can certify and bring on station. Ultimately we are working toward establishing a large population of golden shiners on the station that will be used specifically for sheepnose production.
In July we were able to collect several gravid sheepnose and use their larvae to infest nearly 1,500 golden shiners which were placed in our mussel culture cages at one of our established mussel culture locations. By facing these challenges we learn more about fresh water mussel propagation and help to prepare ourselves for the future. By working to protect the sheepnose we also protect the places that it calls home. From the Chippewa River to the Mississippi River Basin everything is connected and it is our job to understand those connections. Here’s to a successful year of sheepnose production and ultimately improving our natural places.