Complex sentence: The Aquarium is one of only four facilities in the nation where you can see Steller sea lions or Northern fur seals, as well as being the first to attempt artificial insemination on a Beluga Whale.
Split into simpler sentences: The Aquarium is one of only four U.S. facilities nation where people can see Steller sea lions or Northern fur seals. It is also among the first aquariums to attempt artificial insemination on a Beluga Whale.