There are 39 known distinct species of crawfish that live in Louisiana ponds, streams, and rivers. But it is procambarus clarkii, the red swamp crawfish, that we typically turn an even brighter shade of red every year between Mardi Gras and the end of June.
"Those are what we had in our natural habitats for tens and thousands, literally millions of years," said LSU Ag Center aquaculture specialist Dr. Greg Lutz.
The white river crawfish also ends up on our tables, but it wasn't until the 1930s and '40s, said Lutz, that people realized that the rice fields across Louisiana were a great way to farm the red swamp crawfish and grow the industry.
There are many more species of crawfish found almost all over the world, and some in New Zealand can grow to be as large as 20 pounds.
So has anyone tried cross-breeding those Kiwi monsters with the native mudbug?
"That was the subject of my PhD dissertation, trying to select for bigger crawfish," said Lutz.
Unfortunately, his research found that it was not feasible.
"The factor that determines the size more than anything else is how crowded they are," Lutz explained.
So in a rice pond or other environment teeming with crawfish, the crustaceans won't grow a whole lot bigger than what you usually find.