Hey all,,, I was on the lake Monday.

I noticed a boat South of South Bass cruising around slowly.. Every now and then it would chirp a siren.. It was a red colored craft. Anyhow whether is was coincidence or not, it took off to the East headed towards Sandusky. Once it was gone for about an hour I could hear a loud underwater noise like and explosion or some kind of thumping loud chirping sound sort of like when ice makes that thumping sound but very loud and under the surface. I am sure some kind of testing was being done... anybody have a clue? It sounded like it was coming from the same area as the boat had been.

Pimplepounder.