On-board Diary: White coral in the Avilés Canyon

Author: Silvia García
Date: June 27, 2008



We reach the Avilés Canyon, 17 miles northwest of Gijón. The canyon drops to almost 2000 meters depth and is one of the deepest in the world, only 8 miles from the mouth of the Avilés estuary or ria. Ye el paraisu de los "Kraken", in other words, it is one of the few places in the world where the Architeuthis dux or giant squid can be found.

This canyon also harbours other treasures: two emblematic species of white coral, Madrepora occulata and Lophelia pertusa. These corals can form reefs that date back more than 8,000 years, but always in cold waters –they tolerate a maximum of 13-13.5 ºC.

A marine protected area has been created in Norwegian waters to conserve the enormous reef there, which is located very close to the coast, is various kilometers long and up to 35 meters high. There, the corals occur at 80 meters depth. In the Cantabrian Sea, we’ve found them at 230 meters depth.

Cold-water coral reefs are considered essential habitats because these ecosystems are used by many species during a critical period in their life cycles. The reefs promote reproduction, mating, feeding and/or offer protection for many species. As such, we were very excited about our discovery. Only 5 minutes worth of filming and an abandoned fishing line threatens us. It was nerve-wracking until we untangled the robot. We took down the coordinates of the location of the coral in order to return and document it in detail.