Bocas del Toro, Panama – Ancient coral reef fossils have exposed the staggering impact of human fishing on Caribbean marine ecosystems.

A new study of 7,000-year-old fossilized reefs reveals a collapse in shark populations and a radical reshaping of the food web.

Scientists from the Smithsonian Tropical Research Institute and international partners uncovered a 75% decline in sharks and a 22% size drop in fish preferred by humans.

In contrast, prey fish species have flourished. On modern reefs, these fish have doubled in number and grown 17% larger — a clear sign of “predator release” caused by the loss of top predators like sharks.

The study used fossil reefs from Panama’s Bocas del Toro Province and the Dominican Republic, comparing them with modern reef systems nearby.

Inside the ancient sediments, scientists found thousands of fish ear bones and shark skin scales — otoliths and dermal denticles — offering an unprecedented view of pre-human marine life.

By analyzing 807 shark denticles and 5,724 fish otoliths, researchers measured changes in abundance and body size across millennia.

While exposed prey fish thrived in modern reefs, tiny coral-dwelling fish remained unchanged, suggesting surprising resilience in some species.

Damselfish bite marks on coral also increased in frequency and size, signaling the rise of prey fish activity on degraded reefs.

The findings challenge assumptions about reef degradation and highlight the long-term ecological consequences of overfishing.

Published in Proceedings of the National Academy of Sciences, the study serves as a crucial baseline for marine conservation.

It reveals what reefs once were — and what might be lost forever without urgent action.

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