DOGGYWORLD.com

"Protect your yard, fruit trees, vegetables, flowers and water features from hungry or destructive animal intruders. The ScareCrow motion-activated sprinkler automatically detects deer, racoons, heron, dogs and more as they approach, and repels them with a short but startling burst of water. The sudden noise, movement and spray scares animals away, teaching them to avoid the area in future.
The ScareCrow:
works day and night without chemicals or unsightly barriers
can be linked to other ScareCrows to form an effective water barrier
conserves water - uses just 2 to 3 cups per deterrence
operates for up to six months on a single nine-volt battery
one scarecrow covers approximately 1200 sq. ft."