Otter tail marks in the sand

I jumped at the chance to hang a camera overlooking this sand beach after noticing the tail tracks made by an otter. This time of the year it had to be a male cruising up and down the river as the females should be having their pups. From the size of the tail marks I would guess a large otter, so I hung a camera in a tree looking down at the beach and wrapped it in moss so it was well hid.