If you come to the Museum and look down from the path into the water as you cross the covered bridge, you’ll see about 10 sunfish patrolling
their nests, swimming back and forth, keeping the nests free from debris and predators.
Here’s some info:
All sunfish are nest builders, and their saucer-shaped nests can be frequently observed along the shoreline of ponds, lakes and streams in late spring. These nests usually consist of a circular depression in silt, sand or gravel that is lighter in color than the surrounding substrate because an adult male has consistently scraped silt, algae or other organic material from accumulating within the nest area. An active, nest-guarding male can often be observed swimming within the nest vicinity, guarding both eggs and newly-hatched young. A few days after hatching, the young emerge from the nest, at which time the guarding parent leaves them to care for themselves.