Walking Scarecrows

(In the absence of Business:Agriculture , this category will have to suffice.)

I was out in the countryside yesterday, and there was some planting going on. Fields were strewn with seeds and there were birds all over the place, munching away. Now, it isn't that I want to deprive the birds of some extra nourishment, but there are plenty other places to eat, and quite frankly at the moment I just want to answer the clearly evident product needs of the farmer.
Below ground, below ploughing depth, set up a number of induction cables (electrical cables carrying a large enough current to induce a magnetic field), along tractor tracks or randomly through and around the field or a number of fields. Make scarecrows, paying particular attention to ensuring a low centre of gravity. Give them more than two legs if necessary. Dress them in luminous or otherwise bizarre clothes; my friend has an astonishing collection of fluorescent underwear, for example. Put induction loops (these pick up the magnetic field on cables which turns it into electricity) in their feet, and EITHER a complicated mechanical arrangement to simulate walking, with knee joints and everything (possible using prosthesis technology, surely?) OR rollerskates built into the feet.
Introduce scarecrow(s) to field. Use solar panels, windvanes, or your own electricity to power the underground cables. Scarecrow happily trots/skates around the field on a pre-designed or random path. Birds eating seeds are a problem no more.

Optional: add upper body mechanics and a limited sound production repertoire, so that when kids come and chase your scarecrows around, they can turn round and go "Blraaah!" with scary outstrecthed arms and growly looking face.

<genetic modification sub-idea>hey wouldn't it be cool if we could have rollerskates built into our feet. With retractable/detachable wheels so you could still walk normally</genetic modification sub-idea>