You have only TWO options with squirrels:

1) Shotgun (my preference).
2) Offer something better: dried corn on the ear works well. This is the more viable option in sub/urban areas.

You could buy a few of those live traps, stick some food in there, and try to catch all of them. If they're too expensive, you might want to try getting some large rat-traps, but make sure they are attached to something so they can't get away. Rat poison might work too. You could also try one of those motion sensor sprinklers just during shooting season.

Another thing, and this works very well for me is get a cat to patrol the area, and you should have no problems. It kills 2 birds with 1 stone because if they're a good hunter, you won't have to feed them all the time either.

I posted my squirrel issue last year here

So this year I armed myself with more chicken wire and I bought a large PVC pipe to cut into rings to create wire mesh sleeves as squirrel protection.

Yet so far this year, nothing without protection has been harmed even with squirrels in the area. I don't know if they are still munching on all their stored acorns or if a trespassing local cat relocated last year's culprit.

I suspect bamboo shoots are not normal squirrel fare, particularly where bamboo is not native. So maybe one developed a taste by chance. I don't know if they teach their friends to enjoy food to which they became accustomed. I guess I'll find out when their stores run low.

I clean my dog pen and place it on the bamboo in a field regularly visited by rabbits, squirrels and deer. This not only fertilizes the boo and repels the rodents, it also has stopped raccoons from raiding the chicken coop.

I initially started thinking it was deer. We have deer sleeping the backyard frequently. I put fencing around the bamboo and no go. Then tried to spray a water solution of hot pepper no go. Then I noticed the shoots were being destroyed at the ground level or at the fence height. Then I knew it was squirrels. So for the last 4 yrs I would have only less then half the new culms survive. The problem with the hot pepper solution is that its gone when it rains and not strong enough. this yr it is hot pepper in vaseline rubber on each shoot. It seems to work bc squirrel doesnt like the vaseline taste couple with very concentrated hot cayenne pepper in a water proof rub.

nataku-
I hope that works for you. I tried it several years ago and it worked great...for about a month. Even though I kept applying it, they got used to it and went back to destroying my shoots. The only thing that has ever worked for me in this situation is to use 1/2" mesh hardware cloth and form cylinders about 12"-18" high that get placed around the shoots until they get tall enough to be hardened off.