A Surprising Discovery in Patagonian Waters

Jun 4, 2024 | Chile, Marine

Working with the Spanish Institute of Oceanography, the marine program of Rewilding Chile has discovered red hydrocorals in Chile’s Kawésqar National Marine Reserve, located in the Strait of Magellan. This rare and fragile species fosters one of the most biodiverse ecosystems on the planet, according to the International Union for Conservation of Nature, and merits protection. (Header Photograph by Pablo Zavala)

Punta Arenas, CHILE — Scientists exploring the remote waters of Chile’s Kawésqar National Marine Reserve have made an incredible discovery that sheds new light on Patagonia’s little-understood marine ecosystems. They found colonies of red hydrocorals, Errina Antarctica, which had never before documented this far south or at such shallow depths. In high concentrations, these corals form Marine Animal Forests (MAFs), rare ecosystems of exceptional ecological value found on only 0.1% of the Earth’s seabed. The scientific report, “The southernmost Errina Antarctica hydrocoral savannah in Patagonian waters,” has been published in the renowned journal Nature.

The red corals are known to be ecosystem engineers. “The structural complexity generated by MAFs on the seabed is used by numerous species to settle and live, hide, feed or reproduce, so they are also true hotspots of biodiversity,” explains Ana De la Torriente, co-author of the study and researcher at the Spanish Institute of Oceanography. Documented species include sea anemone, sea urchin, basket and sticky ray star, hermit crab, false king crab, sea snails, parchment worms and sponges.

Slow-growing and highly sensitive to environmental impacts, red hydrocorals serve as an indicator of ecosystem health and functionality. They are key to the development of the seabed, but have no legal protection, despite their vulnerable state of conservation, according to the Regulations for the Classification of Wild Species in Chile. Industrial salmon farming, climate change and pollution all threaten their survival.

The colonies of Errina Antarctica documented in the Kawésqar National Marine Reserve range in size from 0.14 to 15.8 cm, and cover up to 28.5% of the seafloor, at depths between 1.23 meters to 33 meters and deeper. Currently, 57 salmon aquaculture concessions are granted within the National Reserve, with 132 new concessions pending. According to Ingrid Espinoza, Conservation Director of Rewilding Chile and co-author of the research, the consequences would be catastrophic for biodiversity. “The results of this study clearly demonstrate the presence of singular and unique ecosystems in the area,” says Espinoza. “We need to implement management plans and strict protections to ensure their long-term survival.”