Fisherman Ibrahima Mar, 55, said dwindling catches have upended a way of life sustained for generations in Rufisque, near Dakar. He described a steady depletion of fish stocks that has left traditional fishers struggling to survive. “The fish have been taken from our path,” he said, pointing to worsening conditions in recent years.

Analysts attribute the decline to a combination of illegal practices and large-scale industrial operations. Bassirou Diarra, Senegal country manager for the Environmental Justice Foundation, said vessels engaged in bottom trawling and other activities often operate under Senegalese flags but are linked to foreign ownership, including European and Asian interests.

“These practices not only reduce fish availability for local consumption but also limit economic returns to the country,” Diarra said, citing issues such as unauthorized fishing in protected areas, non-compliant equipment and lax licensing.

A 2025 report by the Environmental Justice Foundation estimated that 57% of exploited fish populations in Senegal are in a state of collapse, underscoring the scale of the crisis.

The decline has had ripple effects across coastal economies. According to census data, more than 82,000 people in Senegal depend on fishing, accounting for about 2% of the workforce. Ancillary sectors such as fish processing, transport and retail have also been affected.

Local fishing leaders say productivity has sharply declined. Mamadou Diouf Sene, head of the Rufisque Fishing Wharf Revenue Commission, said it now takes up to seven months to catch what previously required two months, reflecting the strain on marine resources.

The economic pressure has contributed to increased migration attempts, with some fishermen undertaking dangerous journeys to Europe in traditional wooden boats known as pirogues. Community members say these journeys often end in tragedy.

Environmental factors have compounded the problem. Researchers note that climate change is shifting small pelagic species, such as sardinella and horse mackerel, northward, further reducing local availability.

Authorities acknowledge enforcement challenges. Cheikh Salla Ndiaye of Senegal’s Directorate of Fisheries Protection and Surveillance said monitoring vast maritime areas remains difficult despite support from security forces.

Efforts to improve oversight are underway, with environmental groups such as Greenpeace introducing technologies including satellite tracking and mobile reporting tools to help identify illegal activity at sea.

The crisis has raised concerns about long-term food security and economic stability in Senegal, where fish remains a central component of both diet and cultural identity.

The analysis, led by Dr. Zeb Hogan of the University of Nevada, evaluated data on more than 15,000 freshwater species and identified a significant collapse in migratory populations across major river systems.

The report highlights that these migrations, which rank among the largest animal movements globally, are increasingly disrupted. Species such as the dorado catfish, which travels an estimated 11,000 kilometres between the Andes foothills and the Amazon estuary, exemplify the scale of these journeys.

More widely known migratory species, including salmon and eels, are also affected.

According to the CMS assessment, freshwater ecosystems are particularly vulnerable to human activity. Pollution entering rivers and lakes, the construction of dams that obstruct migration routes, and overfishing have collectively reduced fish populations.

Rising water temperatures linked to climate change are compounding these pressures.Amy Fraenkel, executive secretary of CMS, stated that migratory species face increasing challenges throughout their life cycles, often crossing multiple national boundaries.

The report underscores that coordinated international action is necessary to address these pressures, particularly as river systems frequently span more than one country.

Migratory freshwater fish support some of the world’s largest inland fisheries and are a critical source of food and livelihoods for hundreds of millions of people. In Cambodia’s Tonlé Sap lake, part of the Mekong river system, more than 100 migratory species contribute to high-yield fisheries, with catches reaching several tonnes within short periods, according to Hogan.

The report identifies 325 freshwater fish species that cross international borders and could qualify for enhanced protection under CMS frameworks. However, only 24 species are currently listed, many of them sturgeon historically targeted for caviar production.

Delegates from 132 CMS member states are meeting in Brazil, where improving river connectivity and protecting migratory pathways form a central part of discussions.

Proposed measures include removing or preventing barriers such as dams, maintaining adequate water flows, reducing pollution, and coordinating fisheries management across borders.

The Amazon basin remains one of the last relatively intact strongholds for migratory freshwater fish. Regional initiatives, including a proposed decade-long conservation plan for migratory catfish, are being considered as potential models for other river systems.

The Mekong basin is identified as a region of acute concern, with large migratory species facing heightened extinction risks due to overfishing and habitat disruption. Key countries in the basin, including Thailand, Cambodia, Laos and Vietnam, are not currently part of the CMS treaty framework.

Other priority basins highlighted in the assessment include the Danube, Nile and Ganges-Brahmaputra systems.

The report also notes past losses, including the extinction of the Chinese paddlefish in the Yangtze River, attributed to habitat disruption following the construction of the Gezhouba dam in 1981.