1. "Herda-hada" or "Herda-hada-herda" can either refer to residents of the Southern American states, the Bible Belt, or any rural area in the United States, especially where "rednecks" can be found. This mostly Southern and Eastern Maryland, West Virginia and Kentucky to the Gulf Coast, and from the Atlantic coast to most of Texas and Oklahoma.
2. It can also refer to the Southern American English (SAE) speech dialect and the mockery thereof.
And he was all like, 'Herda-hada' so I told that stupid redneck to shut up.
"Petting the shark" refers to giving a woman a hand-job. This is due to the fact that at most aquarium shark petting tanks, they require you to pet a shark with the first and middle finger, the same two fingers used to finger your girlfriend.
Side Note: A woman's vagina also closely resembles that of a sharks brain, doubling the connotation.
When you're on the beach and have to take a piss but don't want to go into the water. Instead you lay down, dig a hole near the groin area, and pee in it, much like a turtle does when it lays its eggs.
I was so hungover on the beach I didn't even wanna move, so I just laid a turtle egg instead.