An eight-year-old sea lion at Fresno Chaffee Zoo died unexpectedly on Saturday due to Valley Fever, according to ABC30 in Fresno.

Catalina has been at the zoo for the past six years in the Sea Lion Cave. Medical crews attempted CPR for an hour but were unable to save her.

"We have had it in the zoo, but not for several years. It's not something we see routinely especially not in marine mammals. It's pretty uncommon, so it took us by surprise she wasn't showing symptoms at all. Everything happened suddenly, it was definitely a shock for us," Shannon Nodolf, Chief Vet Officer at Fresno Chaffee Zoo, told KFSN-TV.

The zoo has seen Valley Fever cases before but not in several years.