Thursday April 4, 2024
PhysOrg —
Age matters when determining how to protect life in the ocean; every population needs a strong cohort of adults to produce the next generation. But many marine protected areas (MPAs) are falling short of their most basic purpose: to rebuild struggling fish populations.
In a new study published April 4 in Global Change Biology, scientists looked at the age breakdown of reef fish in marine protected areas for the first time. They discovered in almost all of them, adult fish populations have either flatlined or declined.
“Adult fish are really important,” said Steve Canty, marine ecologist with the Smithsonian Environmental Research Center and a lead author of the study. “They are the primary catch within commercial fisheries that support livelihoods and food security of coastal communities. Additionally, it is the adults that breed and rebuild the fisheries, and here size matters. Bigger and older female fish produce more and better eggs, and therefore are critical to rebuilding fish populations.”