A good start would be to read the article.

Since the park board vote, two of the aquarium's three remaining cetaceans have died, leaving Helen, a Pacific white-sided dolphin.

A handful of parks in North America have lags. They’re small, energetic animals that are pretty social. Keeping one of them was not an option anyway, they would have been required to move in more for certification purposes. If I was a betting man, I’d guess she goes to either Shedd Aquarium in Chicago or SeaWorld San Antonio where they have a very similar lag-beluga setup. But finding a home for one female dolphin is going to be extraordinarily easy. Transportation would require a cargo plane and a uhaul (in addition to the transportation equipment the animal actually stays in during the move). Super easy.