National Zoo’s oldest sea lion, who ‘always kept keepers on their toes,’ dies at 19

Summer, the National Zoo’s oldest sea lion, died June 27 at the age of 19, the Zoo announced Friday. (Courtesy Smithsonian’s National Zoo and Conservation Biology Institute)

Summer, the oldest sea lion at Smithsonian’s National Zoo, was humanely euthanized on June 27, the zoo announced Friday. She was 19.

Keepers with the zoo’s American Trail exhibit noticed that Summer, a female California sea lion, was lethargic and not eating on June 26, according to a news release from the zoo. The zoo’s veterinary team gave her fluids...