Cameroon Fishers Help Document 45 Shark & Ray Species

Ojah Alfred never expected his daily fish photos would help write a scientific "big book." For the past eight years, the 45-year-old fisher has been snapping pictures of sharks and rays using a simple app on his phone, joining more than 80 fellow fishers along Cameroon's coast in an unusual conservation project.

Their work just paid off in a big way. Between 2015 and 2023, these citizen scientists documented over 7,000 sharks and rays, representing 45 different species swimming in Cameroon's waters. The December study published their findings as the first detailed snapshot of shark and ray diversity in the country, filling a knowledge gap that has long blocked conservation efforts.

The news gets serious quickly. Of those 45 species, 36 are threatened with extinction worldwide, including 13 labeled critically endangered by conservation experts. Even more alarming: nearly 90% of the animals caught are juveniles, too young to have reproduced.

Lead researcher Ghofrane Labyedh explains why this matters. When animals are caught before they can have babies, populations lose their ability to bounce back. Species like the blackchin guitarfish and scalloped hammerhead shark, once common sights for Alfred, are now becoming rare.

The research started with a missed opportunity. In 2019, Labyedh traveled from Tunisia to Cameroon hoping to study whales but never spotted one. Instead, she noticed something else: fish markets overflowing with different shark and ray species, yet zero scientific papers documenting them.

She partnered with Cameroonian marine biologist Aristide Takoukam Kamla, who had launched the Siren app in 2015. The app lets fishers record catches offline, automatically capturing location and time. Scientists then verify the data before making it public.

Alfred uses the app while working his fishing nets at Down Beach in Limbe. He doesn't target sharks, but scalloped hammerheads sometimes get tangled in his nets. They swim in groups, he notes, so when one gets caught, others often follow.

Why This Inspires

What makes this project remarkable isn't just the data collected. It's how it transforms everyday fishers into vital scientific partners. These men spend their lives on the water and know its rhythms better than anyone. By trusting them with real research tools, scientists tapped into eight years of observations that would have been impossible to gather otherwise.

The "big book" now gives Cameroon something it never had: a clear picture of what lives in its waters. That baseline helps scientists track changes, spot declines, and push for protections before species vanish completely.

Cornelius John, a 31-year-old fisher from Kribi who joined the project, confirms what the data shows. Most rays in his nets are very young. He's witnessing the pattern firsthand, and now his observations are helping scientists understand why it matters.

The fishers continue their daily documentation, building on their groundbreaking work. Each photo they upload adds another piece to understanding how to protect the apex predators that keep ocean ecosystems balanced and healthy.