Galapagos Islands’ Silent Guardian: The Humboldt Current

14 March 2024 | Galapagos Islands

Like a breath of fresh air, the cold, low-salinity Humboldt or Peru Current sweeps through the Galapagos Islands each year, bringing nutrient-rich water that sustains the archipelago’s remarkable biodiversity and marine life. Discover more about this natural phenomenon and how it sustains a delicate and precious ecosystem.

History

In the vast Pacific Ocean, the meandering and relatively shallow Humboldt Current teems with life; a vital force that plays a pivotal role in sustaining the fishing industry and influencing the incredible biodiversity of The Galapagos. Named after the famed German naturalist and explorer Alexander von Humboldt, the Humboldt Current is caused by the dual forces of surface wind drag and the Earth’s rotation.

It begins its unhurried journey in the icy Antarctica waters, heading north along the coasts of Chile and Peru and then veering west for the volcanic formations of the Galapagos Islands. The current flows year-round but is the strongest during May and December, bringing cooler weather to the archipelago. 

Although the effects of this powerful cold current have been known by sailors and fishermen for centuries, it was first scientifically studied only in 1802 on a sailing expedition in South America by von Humboldt, a Prussian aristocrat, who devoted his life to uncovering the workings of the natural world. Humboldt’s detailed measurements of the current’s speed and water temperature formed the scientific understanding of the Humboldt Current today.

One of the most productive ecosystems in the world, the Humboldt’s plankton-rich waters maintain the marine food chain in the Galapagos — feeding thousands of fish species which in turn generates billions in global fishing revenue — and contribute to the archipelago’s unparalleled biodiversity and staggering variety of flora and fauna.

Upwelling

An extraordinary feature of the Humboldt Current is upwelling, a process where nutrient-rich matter is forced up to the surface from the deep ocean. The Humboldt is one of the largest upwellings in the world, transforming the Galapagos Islands into a haven for marine life. 

A dense population of sea life is supported by the current – from giant squid, to almost 70 species of sharks, whales, sea lions, and other aquatic mammals, creating a snorkeling and diving paradise, one of the best in the world. The upwelling phenomenon also preserves the islands’ biodiversity, attracting not only a large population of marine life but an abundance of rare and fascinating bird species.

Of course, the Humboldt Current also fosters successful fisheries, with around eight percent of the world’s global catch hailing from the areas off the coast of Peru, where the Humboldt provides a steady supply of nourishment for commercial catches, including anchovies, sardines, hake, mackerel and squid.

Cooling climate 

The Humboldt’s importance extends beyond its role as a fertile fishing ground and marine highway. It influences weather patterns, keeping warm, moist air off the coast which cools the climates of Peru, Chile, and Ecuador. Its impact on the Galapagos Islands is particularly profound, impacting both climate and biodiversity. 

The Galapagos Islands, known for its unique biota, can credit its ecological bounty to the Humboldt Current. Stretching a massive 500–1,000 km (310–620 miles) offshore, the current’s chilly, slow-moving waters create cooler weather conditions suitable for species like the Galapagos penguin, the only penguin species found north of the equator.

Climate change

This delicate balance of life is not without its challenges. The Humboldt Current faces disruptions during El Niño weather events, where warm water currents replace the cold currents, impacting weather patterns in the Galapagos. Warming oceans and climate change could have a devastating impact on the marine food chain, affecting the abundance of marine life that depends on the nutrient-rich currents. 

Formerly responsible for 20 percent of the global fish catch, the Humboldt Current now contributes around 6-8 percent, and studies show catches of anchovy in the upwelling system are currently declining. Climate change will bring about consequences to fish stocks, however the Humboldt Current’s importance remains unparalleled – put simply, it’s one of the most vital and productive fishing grounds on earth.

As we marvel at the wonders of the Galapagos Islands and its magnificent array of avian and marine life, it is crucial to recognize the Humboldt as the silent conductor of this ecological masterpiece. From the glacial depths of the Antarctic to the sandy lava shores of the Galapagos, its pole-to-pole journey shapes climate, sustains life and preserves biodiversity in one of the most remote and ecologically important regions on the planet. 

Witness the impact of the awe-inspiring Humboldt Current firsthand on Aqua Expeditions’ Galapagos Cruise. Join us aboard Aqua Mare and see how this vital cold current nurtures and sustains an enormous array of marine and bird life. The water temperature ranges from 19-24 degrees Celsius (or 66 to 76 degrees Fahrenheit), perfect for snorkeling and diving to see this diverse list of aquatic friends.