Howdy...
Yep, I think that's the idea... Sound and Movement... It has actually startled me because the water when it is dumped into the pond is kinda like pouring a quart of water from a foot high into a bathtub, and then when the bamboo swivel piece hits the rock on the back stroke, it definitely makes a "TOCK" sound that will get your attention... This one is about 2.5 feet high because I have it inside my liner with rocks wedging the upright H-frame into place on the plant ledge, the piece of bamboo that collects the water and dumps it is a little over 2 feet long... The bamboo stalk I split in half is probably 6 feet long... Google Shishi Odoshi and there are alot of different ones... Some use small fountain pumps to deliver the water, but since I have the moving water source in my waterfall, I used that... They come in all sizes...
There is a membrane at the nodes of a bamboo stalk that will hold water, and that is what is filling up and causing the swivel piece to become top-heavy and dump the water.... You just have to find the balance spot to insert the pivot piece of small bamboo...
Not sure if it will work on deer or heron, but I am willing to try anything, short of shooting them... LOL...
Take Care... Dave