North American river otters are a playful lot, and fun to watch. They generally have litters of two or three pups, and are normally not camera shy. Typically, the pups are raised by their mom, and dad is long gone.
Otters in Yellowstone National Park can often be found year-round in the Lamar River. But in late June or early July, one or two families will move into Trout Lake, where the native Yellowstone cutthroat trout begin to spawn.