That's how you identify a tarantula hole from a hole that is not as much fun to explore. You look for the soft webbing across the hole. It's a very subtle thing and hard to spot...at least for me....not so much for Jacob.
Then you insert a tiny soft stick inside and "tickle" it out. It thinks it food and is intrigued and either comes out fast and quick or more tenuous and slowly. You never know.
You can also pour a little water into the hole and that encourages them to come out.
Jacob will sometimes start digging to discover the tunnel of the burrow if he thinks it went way down into it's hole. He gets in that hunter mode.
Now wasn't that interesting?