I've lived in DC for a few years now but only just last weekend made it to the National Zoo. It's a good zoo, as far as zoos are concerned, but I wasn't incredibly impressed. I suppose that without being able to charge for admission they're somewhat restricted by how much new investment can be done.
Anyway, I had a nice time and really liked seeing the big cats. It was the middle of the day and warm out so the lions were doing exactly what all cats do during a warm afternoon, napping. Just as we got to the lion exhibit, one of the trainers took a giant piece of cow leg out of a bag and hurled it across the moat. The cow hock landed with a loud thump, and just like when I shake my cat's food bag, the lion immediately sat up and bounded across his enclosure over to the food.
And just like my cat at home, it didn't take the lion very long to finish off his meal and wander back to sleep.