Have you looked for horn worms? I usually notice the black "turds" and then find the worms. I pick mine off and feed them to the chickens. (The worms).

Those are the wrong shape for hornworm droppings (which look like little blackberries).

I think these look more like droppings than dead bugs. Whenever you see bug droppings, look above where the droppings are. If something's eating your plant, you should notice pieces missing. Of course, the more droppings, the more plant they'll have eaten, and this doesn't look like much ... though it might be that the rest of the droppings didn't land on a leaf.

Oh dear. This is embarrassing. My dad mentioned in passing that he put down milorganite around an area to help protect against deer. Problem solved! I appreciate the responses nonetheless.

Ditto cymraes! The chickens love 'em.

Take the time to find the hornworm...look above where the frass was found. They blend in incredibly well and are often lying right along the stem - pull them right off - they may barf on you (chewed tomato gunk) - but they need to be removed and destroyed to save your plant from be eaten up.

Thank you