GAAAA THERE IS A HUGE SPIDER IN MY MAILBOX

At the moment, he and I have reached a kind of detente; our agreement involves my gently poking him with a stick, and him angrily waving his pedipalps while ceding the high ground to me long enough for me to grab the mail. However, I'm a little worried. He's awfully big... there's nothing to say he won't start opening my mail and signing for packages while he's in there.