we did that about 10 years ago before they really tightened down what you can and can't do. We actually took our own boat and anchored in there for the night and it was fairly isolated at the time so no crazies....and there were no clear or posted regulations about swimming with them....I am not sure if you were able to see or experience it, but when the moms swim by with their calves they move them under their bodies and they emit almost a dolphin like sound and the baby answers repeatedly until they swim past you....it was so awesome to witness!!!
One swam past me so fast (who knew that they could go that fast they are so fat lol) and knocked me right over ....awesome experience...glad you posted this as it made me go back in time and remember what was an incredible weekend that I had forgotten about!!!!
I don't remember anymore if this is steve or me LOL