eat them, lots of meat in the legs. meant to be very tasty.
theres nothing you can do to stop them eating your bait, when they swarm in they are everywhere.
use a wire trace for your hook length it stops them cutting through it. for bait try crab, squid or cuttle, it wont stop them but the tuffer flesh slows them down.
if you find any small spiders/or peelers, use them as bait, the smutts love them.
depending where you are and how big a swarm you get the best thing you can do is fish else where. at gosport and other areas in the solent they get so bad the fish stand no chance of finding your bait. went fishing last year, and there where thousands of washed up shells on the beach from where they had just peeled. we left and fished else where.