This is a group of three Nutria, sharing a log in Delta Ponds. They have become too numerous along our waterways. At first I thought it was the biggest nutria I had ever seen. Then I realized it wasn't one, but three. I noticed three tails, though the front one is so prominent.

According to the National Geographic website, here are some facts about the Nutria:

Average life span in the wild:8 to 10 years
Size:Head and body, 17 to 25 in (43 to 64 cm); tail, 10 to 16 in (25 to 41 cm)
Weight:15 to 22 lbs (7 to 10 kg)

"Nutria once lived only in southern South America, but they have been domesticated as fur animals and transplanted around the world. In many areas, including Canada and more than a dozen U.S. states, fur farm escapees quickly establish large wild populations near their new homes."

See: http://animals.nationalgeographic.com/animals/mammals/nutria/