In July last year I took this photo in Ramsley Reservoir.  I was told it was a lamprey as no one could think what else it could be!

If you have any ideas then please let me know. Email me at:  rogert365@gmail.com

The following link is to the first Flickr image.  There are 2 more photos following on.  You do not need to be a Flickr member to see them:

http://www.flickr.com/photos/bigmoor/10169623204/in/photolist-fEC8QS-guDYF7-fwuAtb-fwfrma/

Since writing this post I have had feedback from several people and the consensus is that this is a leech.  It is the biggest one I have ever seen but there again, that is not too many.  Several quite knowledgeable people still believe this is a lamprey but I must admit that the strength of the leech argument is winning me over.