I went out to the mooring tonight and the entire aft end of the boat, including decks, mainsail cover and Bimini, was liberally covered with large droppings. As we approached the boat an osprey took off from our upper spreaders.

I happened to have some metallized Mylar "flash tape" aboard and used the spinnaker halyard to rig a line of metallic streamers every few feet, attached to an Amsteel line strung tightly from the foredeck to above the upper spreaders. These metallic tapes are about 2-3 feet long and will stream aft in the wind just ahead of the mast. Hopefully will do the job.

Anyone have other suggestions?