Millions of people’s food supply depends on super-urinating fish
The mangrove-lined estuary on Abaco Island in the Bahamas. (Craig Layman/)For the mangrove forests that line the coast of Abaco Island in the Bahamas, fish pee is a precious resource. While fish such as cubera and gray snappers roam the mangroves in search of a meal, they excrete “fish pee” through their gills which, among other substances, contains the valuable nutrient nitrogen. However, it turns out that some of these fish do more than their fair share of this important and messy work, scientists reported February 26 in the journal Science Advances.These MVPs spend more time swimming around their mangrove homes than other members of the same species. The busy fish spread more nitrogen around during their wanderings, fertilizing the mangrove trees and algae growing on their roots so they can grow lush and feed the fish, crabs, and other animals that people depend on in turn.“There are certain individuals...