Looks like the larvae (caterpillar) of the beautiful Black Swallowtail butterfly. Do you have parsley, dill, or other members of that plant family nearby? The butterflies uses plants in the Apiaceae family as a host.

I won't use any of those plants in my gardens for this very purpose, lol. I provide adult butterflies and moths with nectar plants, but I'll be darned if I'll set up a smorgasbord of caterpillars for all of the birds, of which I have zillions.

The only host plant I've installed on purpose are my tomato plants. So far, I get to harvest plenty of healthy tomatoes, the hornworms get to 'harvest' plenty of leaves, and the robins are fat. Thus, a balance has been created.