I received this intriguing set of photos taken by a boater on the Housatonic from Leon Sylvester Jr. The story passed on to me was that of a mother fox and her cubs hanging out by the river edge (first photo). The boater could see a coyote stalking her, and threw something in its direction to alert the fox, who immediately defended her kits from the intruder.
I suspect the "fox" may actually be another coyote. Fox are about 12 pounds, while coyote are closer to 30 lbs, so there is a big size difference.