@Novaleigh, you make a great point. I have chicks brooding in my garage and had to stop myself from spraying an egg sack I found this morning. I guess I'll have to swipe it and put it in a jar with a cotton ball soaked in nail polish remover. Squishing that could release too many tiny bws.
I had been wondering about whether chickens can eat black widows, we have tons around our place. I know many kinds of venoms are okay to ingest so long as they don't get injected into an animal's system (you can actually eat rattlesnake venom, not that I would). Has anyone ever had a bird die from a spider bite, or would it be really hard to tell if it did?