Thanks for all the ideas and links to different chargers. 

We started getting huge increases in bear damage about 5 years ago. Within a
couple of years we were losing about 250 hives a year. We tried to get help
from the state and that was a total waste of time in Michigan. The state is
promoting the bear population. 

Putting up fences turned it around. You can only go out and sit waiting for
bears with your rifle so many nights getting bit by mosquitoes, etc. ha ha.

Here's what we did: 
We put up three to five wire fences with tee posts and the newer style black
plastic wire holders that don't break with the snow load and energize it
with the IntelliCharger that we picked up at Premier One. 

http://www.premier1supplies.com/detail.php?prod_id=24359&cat_id=43

They put out about 9,000 plus volts. The beauty of this system for us is the
charger batteries. We buy 9 volt gel batteries that last the whole season
and the unit fits into a deep box that I set inside the fence. 

One could put a solar unit on it that is available, but why bother? The
largest gel battery is about $35 when I buy a bunch of them. That's not too
bad. We buy the larger 165 AH battery. You'll get another year on the
batteries with solar, but the cost outweighs the benefits and they will
attract attention.

I started out with the 20B model, but have switch to the newer bigger
brother. More joules!

http://www.premier1supplies.com/detail.php?prod_id=379&cat_id=44

This keeps out most black bears and the costs is bearable.(couldn't resist
that one)

Sometimes we put barbed on the lower wire just about 4 inches from the
ground to keep em from digging under the fence. Sometimes I put only two
smooth above that. 

If the bears give more pressure, than we'll add another wire or two. Maybe
even a barbed wire.

I build them so I can step over(step high or else)

A good ground is very important. I get 2,000 more volts between the ground
wire and hot, than I get between the actual dirt ground and hot wire. 

First wire....about 4 inches high.
Second wire....about 8 inches above the ground
Third wire.....right at crotch level
Add more to suit.

This simple setup keeps out most bears. Be sure to weedspray with roundup.
No weeds. No weeds. 

I also like the black and white braided poly that is about as thick as a
pencil for the top wire and gate lines. Deer and snowmobilers can see them.
Premier also carries this. Get the better grade. You can weave the ends back
on themselves through the braid and they hold well.

Kirk from Sleeping Bear Farms  www.sleepingbearfarms.com  

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