'Observation, not interaction' is the mentality here. Guided tours stroll along the beach (or boardwalk on self-guided tours; adult/child/family $16/13/42.50) to a colony of (mostly sleeping) Australian sea lions, endemic to SA and WA (there are only about 14,700 of them left in the wild). Book tours in advance; lots of extra tour times during school holidays. Last entry 45 minutes before closing time.
Seal Bay Conservation Park
Top choice in Kangaroo Island