It is common knowledge that coral reefs provide essential habitat and food for fish. Proving that the relationship between coral reefs and fish are much more complex and enduring, scientists have discovered that corals reefs are as much dependent on fish.
A study published in journal, Nature Communications revealed that coral reefs greatly depend on fish for nutrients that help them grow and survive.
As explained by Phys.org, phosphorus is released into the water when fish urinate. The phosphorus, along with nitrogen excreted as ammonium through the gills of fish, is crucial to the survival and growth of coral reefs.
In lieu with exploring how overfishing affects the ecosystem processes, researchers studied a site in the Carribean where overfishing is apparent. They concluded that in the sites where commercial fishing commonly occurs, fish-mediated nutrient capacity is reduced almost 50 percent despite no substantial changes in the number of species.
"Part of the reason coral reefs work is because animals play a big role in moving nutrients around," lead author Jacob Allgeier, a postdoctoral researcher at the University of Washington's School of Aquatic and Fishery Sciences, said in a press release.
"Fish hold a large proportion, if not most of the nutrients in a coral reef in their tissue, and they're also in charge of recycling them. If you take the big fish out, you're removing all of those nutrients from the ecosystem."
In addition, the researchers also found out that the large reductions in fish pee were driven by the loss of predator fish such as grouper, snapper or barracuda.
"Simply stated, fish biomass in coral reefs is being reduced by fishing pressure. If biomass is shrinking, there are fewer fish to pee," Allgeier said.
The study suggests that the dying corals can recover if people refrain from fishing large fish. The study especially provides help in proposing solutions in line with the ongoing coral bleaching that has depleted the quality of marine ecosystems.