Gulfarium, Ft. Walton Beach, FL.
In 1966, while going through Navy flight training in Pensacola, FL, I read a short science fiction story (probably in Analog Science Fact/Fiction) about a researcher who was attempting to establish communications with porpoises.
In the story, the researcher donned face mask, flippers, air tank, regulator with associated paraphenalia, and weights, and spent copious amounts of time amongst porpoises in his research tank. Much to his chagrin, they ignored his overtures.
Then, he realized that he was overdoing it with his scuba gear. He shucked tank, regulator, and weights, and, armed strictly with face mask, trunks, and flippers, swam amongst them, doing the dolphin kick. They warmed to this compromise and communications ensued.
Then one day I recalled that there was a porpoise facility only fifty (highway) miles east of Pensacola, the Gulfarium, at Ft. Walton Beach.
Just for kicks, I thought, I'd like to try what the fictional researcher had done. (I had spent half of my youth under water with face mask and flippers.)
Off to the Gulfarium!
Once there, I told the manager about my being in the Navy, and the gist of the SF story. Would it be possible for me to swim in the tank with his porpoises, like the guy in the story?
"You say you're in the Navy?" He asked.
"May I see your ID card?"
He studied the ID card a bit.
"OK, but you'll have to do it between shows."
When the time came to enter the tank I asked the manager, "Any special precautions?"
"No. They should pretty much ignore you." (Seems like there were four or five porpoises and about three sea turtles in the tank.)
Just before I entered the water, the manager called out, "Oh, one thing. Don't mess with the smallest sea turtle."
"He bites, right?"
"No. That's not it at all. That smallest turtle is a pet of the biggest porpoise. She walks it around the bottom of the tank like you'd walk your dog. She's nice and won't bother you, but if you mess with the turtle, she'll bump you."
Into the tank!
As advised, the porpoises pretty much left me to my devices. I swam the dolphin kick all over the place, coming up for air, as required, but, other than being washed about in their wake turbulence, I could perceive no curiosity about the stranger in their midst.
Just before I exited the tank, I was swimming upside down and angling downward toward the bottom south side of the tank. When I got to about two feet from the bottom, I uprighted myself, and found myself one foot from the smallest sea turtle. Three feet to the left, was the biggest porpoise, looking at me.
As I climbed up onto the enter/exit platform, one of the porpoises (don't recall which one) was just below the surface, watching my exit.
At that point, it dawned on me. If any inter-species communications occurred today, it consisted of the large porpoise thinking:
"They told him."