Confidence: I'm as sure as I can be.
Notes: Several spraints had been found yesterday by upland lakes before a regularly used latrine was found also. It contained many spraints of varying ages, some appeared fresh enough to be that days. The site is on the edge of a small lake and is surrounded by rushes through which the otters have made a tunnel for approaching the latrine. Frog bones seem to be the most obvious component but the most surprising thing was a gammarus shrimp from either one of the streams or lakes nearby, small prey for an otter. Maybe the otter ate the shrimp or alternatively the shrimp was within the stomach of a fish or frog that the otter dined on. See last pic. Invertebrate remnants such as beetles and dragonfly larvae seem to fairly common in spraints in the area.