Ugh, flea beetles have been my worst enemy the last few years, and can (have) destroy entire beds of sprouted seedlings in a day or two. One year they did their best to completely de-leaf a willow tree. They are terrible and indiscriminate little beasts. I seem unable to anticipate their appearance, which I swear is earlier each year - what have you found works best against them?
I promise to go back to chickens only after this. But I've had wonderful success using beneficial nematodes to rid the garden of flea beetles. It's a lot less convenient than sevin or permethrin as you usually have to mail order them but they work very well w/out using poison for that.