05/27/2026
The Giant Floater (Pyganodon grandis) is a large, up to 10 inch long, freshwater mussel which is very abundant in Findley Lake.
As a typical bivalve (2 shells) mollusk, Giant Floaters are filter feeders. They siphon water containing plant plankton and organic debris through their body filtering out the plankton and other organics as food. Therefore, they actually do a great job of cleaning our water.
Although Giant Floaters can, and do, move around on their own, they rely on fish to disperse their offspring throughout the lake.
Reproduction:
The eggs of the Giant Floater are fertilized inside the female mussel and held as a brood till water temperatures rise in the summer months. The fertilized eggs develop into glochidia, a larval form of mussels without a hard shell.
When the water temperature increases, the glochidia are released into the water. These larval Giant Floaters pass through the gills of fish swimming in the area. As they pass through a suitable host fish, they attach to the gills of the fish. Giant Floaters have been known to use a variety of host fish including bluegill, black crappie, largemouth bass, and a host of others.
While attached to the fish’s gills, the Giant Floater larva develops into a tiny, juvenile mussel. The young mussel is shed into the water where it lives on the lake bottom growing into adulthood.
The period of development in the host fish only lasts from a few days up to a few weeks. This process has little to no effect on the fish and embedded glochidia does not pose a hazard to humans eating host fish since we do not generally eat fish gills.
Giant Floaters are regularly eaten by Raccoons, Mink, and Otters among others.
It is important to note that in Ohio, mussels, or mussel shells may NOT be taken, possessed, or collected for any purpose.
This rule is in place to protect several endangered and threatened species of freshwater mussels native to Ohio.
References:
https://animaldiversity.org/accounts/Pyganodon_grandis/
https://en.wikipedia.org/wiki/Pyganodon_grandis
https://dam.assets.ohio.gov/image/upload/ohiodnr.gov/documents/wildlife/laws-regs-licenses/OhioFishingRegs_English.pdf
https://codes.ohio.gov/ohio-administrative-code/rule-1501:31-17-01
https://animaldiversity.org/collections/contributors/biodidac/uniolifecycl2/
https://www.fws.gov/media/freshwater-mussel-lifecycle