Well they definitely climb ladders. Years ago when we were building our house, we were dog sitting my stepfather's poodle.

We'd left a very long ladder leaning against the siding on the high wall of the house while we went inside for lunch. We heard a very plaintive cry and discovered that Beau the poodle was not with us.

After searching the yard we found him on the of top of a 22' ladder. He'd mastered ladders but he wasn't certain how to turn around and climb down once he'd reached the top rung of a ladder propped against a vertical wall. Seems he used to follow my stepfather up and down ladders when he was doing roof repairs and must have thought all ladders lead to a roof with his owner and a good view.