What the otter had for dinner update.
6th April 2012: The half eaten pike and the separated back section of its spine, has disappeared from the river bank. Looking again at the photograph, the fish seems to have a mouth full of gravel. Perhaps it was already dead and an otter had pulled it out onto the bank, or maybe a flood washed it there. However it arrived on the bank, it is likely that an otter had eaten some of it; there was an otter spraint 300mm away, on horizontal tree trunk. I guess this will remain a mystery.