I don’t know if there is an official term for the way swan dig with their powerful webbed feet to dislodge plants rooted in lake sediments, but I call it dredging. They create ripples of circles around their bodies as they move from side to side digging deep into the lake or creek bottoms. It looks like they are marching in place.
Mallards also profit from the dredging action as the digging brings up plant parts and other buried food. I usually find a few ducks tagging along with the swans, who don’t seem to mind sharing.
Canada Geese also like hang out with the swans and ducks, probably hoping to get some of that dislodged vegetation.
A peaceful late fall scene on the shore of Sucker Lake in St. Paul.