Hello Emilly,
 
Whatever you do,do not shoot the bear with a .22
It will only aggravate him. He could easily turn
his attention from bird seed to you. The doors
to most houses would not stop an angry bear either.
 
Call Fish and Game, They will advise you.
Bears are wild animals and extremely strong.
I have seen the remains of trees ripped apart by
bears to get the ants inside.
 
 
For starters clean up the bird seed,and any other
food lying about.(Wait for the bear to depart, of
course.)
 
Bears become a nuisance when they become "Pets",
by  so called "Animal Lovers," feeding
them. Wild animals should be just that, wild.
They do not need any help from man to exist.
They will loose their fear of people and that
is when the trouble starts.
 
The best that can be hoped for then is that Fish
and Game officials can capture it,(Not often successful.)
The worst case involves the yuppie fed bear being
killed by Fish and Game people. (Dart tranquilizers
work in the movies, In real life they often kill the
animal. If not killed by the drugs they then wander
about in a drug induced stupor, extremely stressed out,
and die later.
 
I lost my(then) one and only hive to a bear a few years ago.
I have an electric fence now. We got it working just in time
too. My wife saw a bear cub just 200 yards from our house,
and apiary. We live in the country with lots of wild
game close by. I have lost several cats to coyotes
and fox over the past decade. Bear sighting are
common, as are turkeys, and deer.
 
I can help you with and improved diagram for the
circuit of an electric fence, not the electronic
part but the fence itself.