Module 116 · Ocean Systems
The Sardine Current
From Galicia to Senegal, one river of cold water
feeds eight nations. 5,000 kilometres of upwelling.
Morocco cans half the world’s sardines.
Portugal’s stocks collapsed 80% in a decade.
Same current. Same fish. Two very different stories.
The Canary Current is one of four major eastern boundary upwelling systems on earth. It begins at 43°N off the coast of Galicia and Portugal, flows southward along Morocco, Western Sahara, and Mauritania, and dissipates near Senegal and Guinea-Bissau at roughly 10°N. Scientists formally call it the Canary/Iberia Current Upwelling System. It covers 1.1 million square kilometres.
The mechanism is elegant. Trade winds blow parallel to the coast. The Coriolis effect pushes surface water offshore. Cold, nutrient-rich water from the deep rises to replace it. Phytoplankton bloom in the sunlit nutrients. Sardines eat the plankton. Everything above eats the sardines. The entire food chain hangs on wind direction and water temperature.
These upwelling zones occupy 5% of the ocean but produce over 20% of the world’s fish catch. The Canary Current alone sustains the fishing economies of Portugal, Spain, Morocco, Western Sahara, Mauritania, Senegal, the Gambia, and Guinea-Bissau. The same cold water that cools Essaouira’s summer air feeds Dakar’s protein supply.
The System
5,000 kilometres of cold water
Blue dots: current waypoints. Diamond markers: fishing ports by country. Click any point for data.
Oceanography
Three zones, one system
The Divergence
Portugal’s collapse. Morocco’s dominance.
Iberian sardine biomass crashed 80% between 2006 and 2016. ICES recommended a total fishing ban for up to 15 years. Portugal rejected it. Quotas were slashed instead — 56,604 tonnes shared with Spain, two-thirds to Portugal. The Santos Populares festivals now serve increasingly expensive sardines. 20,000 jobs depend on the fishery. Prices tripled in five years.
World’s largest sardine exporter. Half of all canned sardines in global supermarkets are Moroccan. Sardines are 62% of total fish catch, 91% of raw material for the canning industry. But the collapse is accelerating: landings fell from 965,000 tonnes (2022) to 525,000 (2024) to 419,000 (2025) — a 57% crash in three years. On February 1, 2026, Morocco banned frozen sardine exports indefinitely. UK importers report supply “non-existent” in some periods. Prices surged 60%. In May 2025, the Competition Council launched a price-fixing investigation. The cause: overfishing (RSW trawler fleet expansion in Dakhla), weakening upwelling from climate change, and water temperatures shifting beyond sardines’ 17–18°C optimum. The abundance era is ending.
Landings
Two trajectories, same ocean
Sardine landings (thousand tonnes). Different scales — same warning.
2025: Morocco landings fell to 419K tonnes (down 57% from 2022 peak). Frozen exports banned Feb 1, 2026. Portugal quota: 29,560 tonnes (stock recovering).
Global Context
Four upwelling systems feed the world
Together: over 20% of global marine fish catch from just 5% of ocean area.
When the current weakens, Senegal goes hungry
In Senegal, 600,000 people work in fisheries. Sardinella — the tropical cousin of the European sardine, thriving in the same upwelling — is the primary source of animal protein for millions. It is not a luxury. It is survival.
Climate change is warming the system. Fish stocks are shifting north as water temperatures rise. Round sardinella, which prefers 22–25°C, is expanding into Mauritanian and southern Moroccan waters. European sardine, which spawns at 16–18°C, is retreating. The distribution map is being redrawn by physics.
Meanwhile, Mauritania’s fishmeal factory boom has exploded sardinella processing from 10,000 tonnes in 2009 to 70,000 by 2013 — fish ground into powder and shipped to aquaculture operations in Europe and Asia. Half a million tonnes of small pelagics transit annually from West African ports to Lagos, Abidjan, and Douala. The Canary Current feeds a chain that stretches across the entire continent.
When Morocco didn’t renew its fishing agreement with the EU in 1999, over 300 European vessels — many Spanish and Portuguese — lost access to Moroccan waters overnight. The pressure shifted south to Senegal and Mauritania. Fishing agreements are geopolitics. The sardine is the currency.
The wind blows south along the coast.
The cold water rises. The plankton bloom.
The sardines come. The nets go out.
In Lisbon they grill them over charcoal in June.
In Safi they press them into tins.
In Dakar they dry them in the sun and call it life.
One current. Eight nations. The same silver fish.
Sources
NOAA / Springer, "The Canary/Iberia Current Upwelling System" in Upwelling Systems of the World (2016). 43°N to 10°N.
Morocco World News, "Morocco, World’s Leading Exporter of Canned Sardines" (Jan 2023). 152,137 tonnes, MAD 5.9B.
SeafoodSource, "Morocco indefinitely bans export of frozen sardines" (Jan 2026). Landings 965K → 525K tonnes (2022–2024).
Telquel.ma, "Why Morocco is suspending the export of frozen sardines" (Feb 2026). 2025 landings: 419,474 tonnes (−23% YoY).
The Grocer / Assosia, "Tinned sardines shortages loom as Morocco supply non-existent" (Jun 2025). UK supply disruption.
Morocco Competition Council, formal investigation into sardine price-fixing (May 2025).
ICES Advisory Report: Iberian sardine biomass 106K (2006) to 22K (2016).
Nature Scientific Reports, "Climate change impacts on small pelagic fish, NW Africa" (2024). SST +0.3–0.4°C/decade.
ScienceDirect, "Fisheries of the CCLME" — 1.1M km², Morocco to Guinea-Bissau.
Earth Journalism Network, "Portugal Faces Collapse of Sardine Fishing Industry" (Jul 2022).
National Geographic Portugal, "Can Portuguese sardines make a comeback?" (Sep 2022). 2019 quota: ~10,000 tonnes.