Does anyone know why some birds, or maybe all birds, will not eat the caterpillars that attack our brassicas at this time of year. That is the Cabbage White. Certainly 'my' Great Tits and Robins won't touch them.
edited October 2022
After caterpillars have feasted on your brassicas, they are full of mustard oil which is toxic to birds.
Thank you, Rose Pink. I didn't know that. most interesting.
We had much trouble with whites on the sprouts. Then thought all was ok and actually picked some sprouts (not caterpillars!). Then this week we find the plants covered with caterpillars again. Our fault for not netting.