One man’s trash is another man’s treasure. In the case of sea urchins and shrimp, that statement could be refined to say that one species’ waste is another species’ dinner. Admittedly, the concept might sound a little gross, but a team of researchers from the University of Alabama at Birmingham say using sea urchin waste to feed shrimp helped the crustaceans grow faster, bigger, healthier and even tastier than using traditional food—and the process is more sustainable, as well.
The research is being led by Steve Watts, Ph.D., whose previous work with sea urchins led him to be featured on the Andrew Zimmern–hosted show Bizarre Foods America. “In some cases, we had our shrimp together with our sea urchins, and they did very well, and we noticed that the shrimp had a tendency to congregate by the sea urchins and consume the waste pellets from the urchins,” Watts said. “It looked like there might be some kind of synergy there.”
Watts’s team put together a “polyculture system” where sea urchin pellets were allowed to drop through to feed shrimp living below them. “When you have urchins present, you won’t need the shrimp feed,” said Watts. “What we’ve found is that the shrimp do very well when just consuming the urchin pellets alone—they grow large fast and stay healthy. In many cases, they exceeded the growth rate of shrimp fed the expensive feed.”
Renowned local Birmingham chef Chris Hastings, owner of Hot and Hot Fish Club, said the taste of these “poo shrimp” was outstanding, too. “If you did a side-by-side with any shrimp grown in a pond in the world that’s not done sustainably in a closed loop with organic food as its source in a clean environment, and you taste it next to this shrimp—the flavor, the texture, everything about your shrimp is world-class compared to that,” the chef said.
Watts hopes that, beyond just enhancing shrimp production, research like his can help create more sustainable aquaculture systems by delving deeper into polyculture relationships—which is a fancy way of saying that if everything can live off everything else’s poop, then maybe we don’t even need any food at all. Now that’s sustainability!