The research, published in the prestigious scientific journal Coral Reefs, shows that the black coral forests of the Canary Islands archipelago are home to unique fauna communities on each island
This scientific finding confirms that various species associated with these marine habitats show changes in their form and diet depending on the island environment and local resources, revealing an adaptive pattern
A study by the Biodiversity and Conservation Group (BIOCON) of the ECOAQUA University Institute of the University of Las Palmas de Gran Canaria (ULPGC), recently published in the prestigious scientific journal Coral Reefs, has shown that the black coral forests of the Canary Islands archipelago are home to unique fauna communities on each island. This research confirms that several species associated with these marine habitats exhibit changes in their form and diet depending on the island environment in which they develop and local resources, revealing an adaptive pattern.
This scientific advance in understanding the biodiversity associated with these marine ecosystems has been made possible thanks to the research of ULPGC doctoral students Sandra Navarro Mayoral and Sonia Díaz Vergara, focused on the DEEP LIFE project on the study of black coral forests in the Canary Islands, led by ULPGC professor Francisco Otero Ferrer, a researcher with the BIOCON group at ECOAQUA.
The scientific team analysed the fauna associated with black coral forests on three islands: Lanzarote, Gran Canaria and El Hierro, resulting in the first global description of the distribution of fauna associated with black corals along a longitudinal gradient.
Mesophotic black coral forests formed by black coral (Antipathella wollastoni) at a depth of 60 metres in Lanzarote, where samples of the associated fauna were taken. Author: Fernando Espino.
The results revealed the presence of a rich fauna community dominated by 92% amphipods, small crustaceans that live on corals. This is not the first time that this group of researchers from the ULPGC has highlighted the ecological value of these associations. Just a year ago, they described a unique genus of amphipods in the black coral forests of Lanzarote.
The research was carried out at a depth of 65 metres, using non-invasive techniques that allowed the fauna associated with the corals to be collected without damaging them.
In the laboratory, researchers Sonia Díaz and Sandra Navarro measured the body size and gnathopods (the claws of amphipods used for feeding or reproduction), as well as analysing their diet based on stomach contents.
Same species, different sizes or diets
The data obtained showed differences depending on the island: the same species could have different body sizes and contrasting diets. For example, while in Lanzarote one species was mainly carnivorous and small in size, in El Hierro the same species was larger and combined carnivorous and herbivorous habits.
According to the researchers, ‘amphipods are organisms with poor swimming ability, so populations tend to remain where they are born. They are excellent organisms for understanding local adaptations and impacts on the ecosystem.’
A species of amphipod, the main inhabitant dominating the mesophotic coral forests of the Canary Islands archipelago. Author: Wilfried Thomas.
ULPGC professor Francisco Otero-Ferrer points out that "our results show how species associated with black corals adapt to the conditions specific to each island. In the Canary Islands, there is an east-west gradient of temperature and nutrients that directly influences life in these ecosystems. In El Hierro, for example, the waters are warmer and poorer in nutrients. This allows light to reach greater depths and favours the presence of algae that coexist with black coral forests at a depth of about 65 metres."
In contrast, in Lanzarote, the researcher continues, "the waters are colder and richer in nutrients due to the Canary Upwelling. There, light penetrates less and most algae do not find suitable conditions for life, leaving the forests dominated by non-photosynthetic organisms such as sponges and ascidians. These differences in the environment also influence the fauna that inhabits these underwater forests. In Lanzarote, their diet is mainly carnivorous, while in El Hierro it is much more varied," he concluded.
This finding was published in the journal Coral Reefs, in an article led by ECOAQUA researchers from the ULPGC: Sandra Navarro Mayoral, Sonia Díaz-Vergara, Néstor E. Bosch, Ricardo Haroun, Fernando Tuya, Fernando Espino and Francisco Otero-Ferrer; and with the collaboration of other renowned researchers such as Victoria Fernández-González, from the University of Alicante; Lorenzo Bramanti from the LECOB institute at the Oceanological Observatory of Banyuls-sur-Mer (France) and Lucas Terrana from the Musée d'Histoire naturelle et Vivarium de Tournai (Belgium). This continues to advance the frontier of marine knowledge, offering new perspectives on the biodiversity and ecology of the oceans.
Beyond its local relevance, this finding highlights the importance of understanding how marine ecosystems function on a global scale. ‘What we learn in the Canary Islands helps us to better understand and protect the oceans around the world,’ Otero-Ferrer points out.
ECOAQUA is conducting this research as part of the European DEEP LIFE project, in collaboration with leading international institutions such as the Centre de Recherches Insulaires et Observatoire de l’Environnement (Criobe, France), the École Pratique des Hautes Études de Perpignan (EPHE, France), the Institut de Ciències del Mar (CSIC, Barcelona), the Stazione Zoologica Anton Dohrn (Italy), the Centre de Formation et de Recherche sur les Environnements Méditerranéens at the University of Perpignan (CEFREM, France), the Università del Salento (Italy), the Université Libre de Bruxelles (Belgium), the French NGO UNDER THE POLE and the Sorbonne University (France), which is leading the project.
The aim of DEEP LIFE is to provide a comprehensive overview of the biodiversity and ecological processes associated with marine forests formed by animals in regions as diverse as the Caribbean, the Arctic and the Mediterranean, generating key knowledge for their recognition and conservation.