 And that's with record high numbers for air travel. Michael Toscano, CBS News, Washington. Sad story, one of the oldest sea lions at the Smithsonian National Zoo has died. Back in late June, one of the zookeepers noted that Summer was acting lethargic and wasn't interested in eating. The zoo's veterinary team provided fluids, antibiotics, and steroids for the 19-year-old, but the follow-up exam the next day turned up signs of kidney failure and possible heart disease.