Since no one has responded for a long time, I'll try offering some info. From what I've read, they don't work that well. I think it's because the sound is too regular, and thus the wildlife (whatever you're trying to scare away) get used to it. I'm not 100% sure about that, possibly someone else can support/dismiss that.

-Audric

I might just try one anyway. We are looking for an inexpensive water feature/ fountain for our pond, and might be able to "kill two birds with one stone" if the deer-chaser works. I am also hoping it would keep hawks/herons away from our pond. Last year, a hawk ate all of the goldfish in our pond. I saw it roosting on our arbor one day and thought "Isn't that cool," until I realized a couple days later it had eaten all the fish. We also have a lot of hostas and other plants in our backyard that the deer love to feast on, so anything that might keep them away or at least irritate them would be helpful.

do your fish have plenty of plants to hide under? if not you should supply them adequate cover.we've had ponds for years with plenty of heron visitors (and kingfishers too) and they never eat ALL the fish, not as long as the fish have some natural habitat.in the beginning we tried to scare away the bird predators and the deer and then realised the smarter thing to do is let them be and enjoy their existence. we plant herbs and trees that the deer don't like and if the birds eat some fish it's no big deal.the deer scare will not work after awhile but they do look nice :)

Our pond is not very large, about 4' long by 2' wide, kidney shaped. It has lots of aquatic plants in it. We had 4-5 goldfish, and the hawks ate all but one within a short period. The final fish disappeared a few months later. Recently my wife has seen a heron in our back yard, apparently checking out the pond, although we haven't restocked it with fish yet. We are waiting for the pond to warm up, and need to install a new pump, before adding more fish again.

BTW, we live near a fairly large nature park on the outskirts of the city. Lots of deer from the park roam through our neighborhood at night, eating all of the gardens and other plants. We also have a lot of hawks, herons, geese and other animals that spill over from the park. We know it was hawks that ate the fish because: (1) I saw one roosting on our arbor near the pond several times the week the week the fish disappeared; and (2) our nextdoor neighbor actually saw a hawk swoop down into our pond, grab something in its talons, and fly off.

a suggestion
those motion sensitive things that give a blast of water seem to be the thing. My neighbour swares by his for chasing away cats etc. You just hook em up to a hose and it takes care of the rest.

To protect your fish you might try laying a short length of clay drain pipe on the bottom for fish to hide in. In a small pool I once turned a plastic crate upside down with large low pot on top with waterlily (whose leaves the fish also could hide under). Fish could swim thru holes in crate to hide. Just be sure pot is heavy and sitting firmly...it was needed partly to keep crate from floating but worked out well to hold aquatic plants. If your pond isn't deep enough (I think mine was close to 32")
you could build a "tunnel" from bricks/clay tiles on bottom ...again. just be sure it's steady and not easily dislodged. Good luck!

josh

speaking of deer chaser fountains Does anyone have instructions for making one? Thanks & happy growing

Steve -

The motion detectors that turn a water hose are good where we live, but they may be less useful in warmer climates where there may be a lot more heavy-duty flying creatures.

Many years ago when I was living on the coast of tropical Africa, the local prison installed motion sensitive alarms to detect escape attempts. After a few week they had to uninstall them. Every night, the hordes of local bats, moths, flying beetles & other insects kept the alarms going off all night long.

Herb

OK, Herb. How did you come to be living on the tropical coast of Africa near a prison? (You wanted someone to ask, right?)

And, Herb, were you inside the prison or outside?

One way you can avoid deer getting used to a noise is use a motion senstive device, like the water sprays coachsmyth mentioned. They sell them for cats on the website I just bought a mouse repeller from, so I guess they would work with deer too! Now I'm looking at the website they do actually sell deer repellers -

Here is a link that might be useful: Deer repelling website!