Don't know if a thread exists for this but I'm wondering which zoos and aquariums worldwide have which pinniped species
Milwaukee County Zoo has Harbor Seals Oceans of Fun inside the Milwaukee County Zoo has Harbor seals and California Sea Lions
For any cases of "I don't know if a thread exists for this", there is a search bar at the top right of the page. There is an existing thread here: Pinniped species in captivity?
The Alaska Zoo displays Pacific Harbor Seals. The Alaska Sea Life Center displays Steller Sea Lions and Pacific Harbor Seals.
I'll list the ones I've visited since 2011: Barcelona Zoo: California sea lion (had harbor seals until around 2016) Oceanografic València: Harbor seal, Pacific walrus and South American sea lion Zoo Aquarium Madrid: Grey seal and South American sea lion Faunia: Steller's sea lions (brown fur-seals off-show when I visited) Whipsnade Zoo: California sea lion Prague Zoo: Brown fur seal Tallinn Zoo: Grey seal Bronx Zoo: California sea lion Central Park Zoo: California sea lion and Harbor seal Ocean Park Hong Kong: California sea lion and Harbor seal Auckland Zoo: New Zealand fur seal