I use the Scare Crow sprinkler on both my ponds, no losses. It has a
sensitivity dial and will even turn on for things as small as robins and
squirrels.

http://www.scatmat.com/Products/Scar...ent=videospage
Has video regarding the Scare Crow "motion detecting" sprinkler. Let us
know if you can find such in your neck of the world. ) ~ jan

See my ponds thru the seasons and/or my filter design:
http://users.owt.com/jjspond/

~Keep 'em Defrosted~
Tri-Cities, WA Zone 7a
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