Has anyone seen birds. . .

The caterpillars of The Large White Butterfly, also known as The Cabbage White, feed on brassica plants containing mustard oils and can store them in their bodies making them distasteful to birds. To vegetable growers the caterpillars of the Large White are one of several vegetable pest species and large numbers can often be seen lying on top of cabbage leaves in full view of birds and yet remain uneaten.

I'll tell you what do like the taste of them ..... wasps.
What a shame the wasps don't seem to be around on our site in any numbers until late August.
Not 100% sure how good, but from last year's observations, those wasps do a mean job, and worthwhile taking off the enviromesh for large bird netting.