Over the last decades, most conservation efforts have been focused on land-based ecosystems. The protection of terrestrial ecosystems has far exceeded marine protection and restoration initiatives. Although we truly live on a blue planet, and the ocean represents 90% of the living space on Earth, we are just beginning to understand the urgency with which we need to attend to the health of the ocean.

As part of my work with Por el Mar, a non-profit marine conservation organisation driven by a team of scientists, activists, communicators, and policy experts, we have been working hard to protect the Mitre Peninsula, the easternmost part of Isla Grande de Tierra del Fuego in Patagonia. The region is Argentina’s biggest carbon sink and is one of the few places that truly remains wild. Home to a large portion of Argentina’s kelp forests, it is also the last refuge for the Southern river otter, a species on the brink of extinction.

While kelp forests worldwide have struggled or disappeared altogether in recent decades, the macroalgal ecosystems along Patagonia’s rugged southwestern coast have “shown remarkable stability for almost 200 years”, according to the American Geophysical Union. Researchers argue that this could be due to frequent marine cold spells in the region which seem to keep the kelp happy. Southwestern giant kelp forests in Patagonia haven’t experienced any extreme marine heat waves since 1984, according to a study published in 2022 in the Journal of Geophysical Research: Oceans, called A Song of Wind and Ice: Increased Frequency of Marine Cold Spells in Southwestern Patagonia and Their Possible Effects on Giant Kelp Forests. It established that the region around the Mitre Peninsula saw extreme marine cold spells between 2014 and 2019, which also grew more intense. Experts believe these localised cooling events could have been caused by glacial melt and increased wind activity. It is well-known that kelp thrives in cold, nutrient-rich waters.

As an example, if the water temperatures go up too much, sea otters might disappear in Patagonia which, in turn, would make sea urchin populations explode. They could then overgraze the kelp forests, as has happened in some parts of California. Combining this with a general loss of kelp forests could be a disaster. In central and northern Chile, for example, unregulated kelp harvesting for the alginate industry has led to annual losses of 2% of kelp forests. In Patagonia, however, the situation is different. Kelp forests look like they did in the early 20th century, according to marine geographer Alejandra Mora-Soto, lead author of the aforementioned study. According to her, when comparing historical nautical charts with modern satellite images of kelp, little has changed.