Okay, the mice are not getting blamed this time :-)
I have seen birds come down and eat the leaves off the pea plants. Two different kinds of birds I have seen do this. One of the birds, a Towhee, in the summer hops up and down my rows of vegetables eating bugs. I really appreciate this and I would speculate that there are not a lot of insects to have as food as it goes into winter.
I guess if I want to have lots birds hopping around in the summer eating bugs I need to feed them in the Fall and Winter! They’re insectivorous but at least people are beginning to realize that animals don’t eat one type of food their entire life. But they are probably not big seed eaters and so I shouldn’t limit myself to bird seed and I ought to plant a few more (salad) peas for them in the fall. And not worry about them eating a few. They will repay me tenfold in the summer. I have also decided to plant my peas earlier so that they are a little bit bigger and thus can withstand the damage better by the time the “bugs run out”. Californians have ripped out all the native plants that used to feed our native animals and planted that one lemon tree in our yard and then are furious that the squirrel gets a few of _our_ lemons. Try planting back some native food plants too. Best to you all!