Fishing may have contributed to slowed Caribbean coral growth as far back as 1,000 years ago.

Many Caribbean locations have seen coral declines and excessive algal growth in past decades, but reef fish such as parrotfish (pictured) can help by eating the algae. Katie Cramer at the Scripps Institution of Oceanography in La Jolla, California, and her colleagues analysed remains of fish teeth, sea-urchin spines and coral fragments in reef cores from three sites off the coast of Panama. They found that over the past 3,000 years, the growth of reefs was driven by parrotfish abundance. A decline in fish numbers and a slowdown in coral growth were seen at all three sites, beginning around 500 to 1,000 years ago.

Caribbean reefs have not recovered from these ecosystem declines, and if the reefs are to improve, there will need to be immediate decreases in parrotfish catches, the authors say.

Nature Commun. 7, 14160 (2017)