Bored on the Ark

It was a quiet day on the Ark and Noah was getting bored, so he told his wife that he was going to relieve the tedium by going off on a fishing expedition.
“That’s a good idea,” she said. “You could do with a break.”
Noah collected his equipment and set off, but thirty minutes later he was back and still complaining that he was bored.
His wife said: “I didn’t expect you back so soon. If you’re that bored, why did you stop fishing after only half an hour?”
Noah replied: “I only had two worms.”