This is going to get some laughs but it works. Go to a craft or bridal shop and buy a roll of tulle by the yard, one manufacturer is "modern romance",Isn't fishing exciting.

Tulle is a sturdy cloth netting. The roll is 6in. by 25 yards. Place herring, sand shrimp whatever in the netting and roll tight. Use stretch twine or rubber bands close the ends and tighten the length of the bait.

It won't keep the crabs away but the bait lasts much longer and I think the crabs trying to tear it apart might bring fish in.

Also makes good egg sacks for steelhead fishing. If you try it and disagree one can always go into the bridal veil business.