A lady up in Northern BC had trouble with a Grizzly sow and two cubs. She put up a electric fence (one wire string) with a cattle charger. It packed a powerful jolt, it keeps a full grown 1600 pound breeding bull where you want him.
The bear hit it once, probably with its nose, and never came back.
Once the Bear knows there is easy food, it will be back until you either stop it or the food source is gone.
Can you move your chickens off the property temporarily?
One way I ensure that animals hit the fence nose first is by baiting it with little foil envelopes full of peanut butter. Peanut butter is good to just about any animal, so everything stops to see what delicious treat is just hanging out there. Works like a charm! I use electrified poultry netting which , honestly, wouldn't stop anything with any determination whatsoever. By using the baits I make certain everything is made aware that the fences are hot before they tear through my fences. Bears can be insulated from a charge by their hair should they tackle a fence any way but nose first.
The honey farmers when they take their hives out to the mountains, use a solar powered fence charger to protect their hives against all types and sizes of Bears. Seems to work for them. Not sure if they bait the lines or not.
If I remember, I'll ask them.
CMV is correct about hair insulating them, i dont have bears, but did have some animals not respecting my electric fence, so i upgraded to a 50 mile charger, and u can hear that hing snap crackle and pop from 50 yards when it gets a victim! my neighbors husky was the first,and the other day, i hit it on accident, and i weigh 200 pounds, and have been around electric fence my whole life(needless to say ive hit it alot), and i had to sit down for a few minutes! P.S., i LOVE the peanut butter on foil idea!!!! OH ALSO, get a box with a pulsating charge, NOT a constant charge, so the animals cant get used to the shock and get ur birds anyway.
I just went to tsc today and bought a charger,just hope bear stays away another nite. I did find out they do not sell a constant shock charger anymore i guess it is not legal. So worried dh working tonight and it is getting dusk,middle of woods i live,just me and the cat until midnight.I do have fire arm protection,just nervous.