Almost half of the worldâ€™s seafood now comes from fish farms, which can cause significant environmental harm if not responsibly managed.
Because many fish are confined to a small area, aquaculture can lead to high levels of pollution and outbreaks of diseases. Sometimes the farmed fish escape, which can hurt wild fish populations and the local ecosystem. Aquaculture can also lead to overfishing since carnivorous fish, like salmon and tuna, are fed large amounts of fishmeal made from prey fish like anchovies or herrings.
The Velella Project is an experiment off the coast of Hawaii that is trying to address some of the problems associated with aquaculture. Instead of enclosing fish in stationary nets or tanks like traditional farming methods, a specially-designed spherical pen, called the Aquapod, drifts through the water containing 2,000 hatchery born fish.