But working with captive dolphins is more complicated now than it was in the 1960's, when little was known about these big-brained mammals and their family structure.

They were further horrified when Universal learned two weeks ago that a "Flipper" promotional prize involved swimming with captive dolphins.

It has been during this period that efforts to return captive dolphins to the wild have picked up.

He also pioneered work to demonstrate rehabilitation and release as a viable alternative for captive dolphins.

He served as Dive Master for a project to reintroduce two captive dolphins to the wild.

Which raises a more intriguing hypothesis: that captive male dolphins attempt these outrageous liaisons out of mischief, or perhaps even revenge.

In 2010, Porter started the 'Free the Pod' campaign, aiming to release captive dolphins back into the wild.

The other captive dolphins Misty and Stormy might join all live at aquariums that wouldn't release them because they were part of established breeding groups.

And Federal rules on how to handle captive dolphins, completed last year, were suspended after swim centers objected to some provisions.

Instead he said, "There are dozens of people doing studies on captive dolphins.