Bird nets

After verasion, and the grapes are near being ripe, they become more attractive to birds. I read of small vineyards being stripped clean in just a few hours. I only will have a small crop this year, but I think I should try to protect them. I looked at possibly buying audio deterrents ... these are recorded bird distress calls, played back at random to deter birds. I also looked at visual deterrents. Much of what I read claims that the visual deterrents are not very affective. And finally I looked at physical barriers.

Audio deterrents
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Pros:
-easy to put up
-lasts many years
-moderate cost
-other growers in Wisconsin claim successful use
-may attract other predators, which may aid in keeping birds out
-unobtrusive visually
Cons:
-Needs AC, or car battery, if battery needs to be changed frequently or recharged
-birds get use to it
-questions about effectiveness
-may bother neighbors

Visual deterrents
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Pros:
-fairly inexpensive and durable
-often easy to erect
-no noise to annoy neighbors
Cons:
-looks goofy with junk all over the place
-unproven or not affective

Physical barriers (nets)
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Pros:
-Very affective
-One time cost
Cons:
-difficult to put up
-difficult to take down
-can be expensive for large vineyards


Since the audio and visual deterrents are not known to be affective, and I only have a few hundred pounds of grapes to protect this year, I decided to get some bird nets. I don't have a lot of vines to cover this year, so I got 4 nets that are 14' by 100'. These should comfortably cover the vines with the most production.