I was surprised to see them in April, but I had lots of dead vegetation in my garden that could harbor them. Sprayed and killed lots of clusters of newly hatched.
"Nasty holes in the fruit that at first I thought were caused by birds."
The damage to tomatoes is much like a bullseye. They 'sting' the fruit and inject saliva-like substance that looks like it damages the flesh in rings.
On the farm we are acutely aware of stink bugs, as they will ruin immature cotton bolls in a heartbeat, and they can destroy soy beans too.
What do you use against them?
One search I did recommended nicotine tea....as we know, tomatoes and peppers need to be kept away from tobacco products. Tomatoes and peppers are a large part of my garden.
OTOH, I have seen these before and haven’t seen any damage that I know are from them in the garden. I will use a pyrethrin occasionally if I see insect damage. I have also used Severin. I have never been that sure the powders are helping, though. I have also not had extensive insect damage in the past.