Fernando Tempera1,2, Ana Luísa Sinde-Mano3,1, David Milla-Figueras1, Pedro Afonso1
1University of the Azores, Portugal - 2UMR BOREA 8067 (Sorbonne Université/MNHN/CNRS 2030/IRD 207/Univ. Antilles) - 3BIOPOLIS-CIBIO
Biological community patterns in vast parts of the oceans are still poorly described even though human impacts continue to encroach into deeper bathymetric strata and faraway regions. The narrow and fragmented circalittoral grounds surrounding the remote Azores islands (central North Atlantic) represent one such gap although they occur within a few kilometres distance from inhabited shores. This work provides the first insight into the composition and distribution patterns of rocky circalittoral assemblages of the most temperate and remote of the Macaronesian archipelagos. A comparative analysis of the vertical sequence of on-shelf physical thresholds suggests that the Azores circalittoral zonation is not abiotically comparable to that of the neighbouring continental shelves of southern Europe. The lower attenuation of downwelling light observed on these oceanic island shelves, together with the shallowing of the shelf break and the wave base, shifts light-related thresholds downwards and shuffles the abiotic framework shaping the circalittoral belts. Modifications in the composition of biological assemblages relative to the neighbouring NE Atlantic continental shelves are investigated using morphological species occurrence data extracted from videos acquired across the archipelago between 20 and 260 m depth. The manifestation of biologically-coherent circalittoral belts is confirmed using multivariate analyses complemented with interpretations relating trait-based vertical segregation of morphotypes with the modified overlapping environmental gradients. EUNIS insufficient representativeness of Macaronesian circalittoral biotope diversity is attested by the numerous new types of multi-phyletic faunal turfs and coralligenous bioherms identified. The preserved status of various of these biotopes and their compliance with a VME classification further calls for properly taking circalittoral habitat distribution into account in the marine spatial planning initiatives aiming to preserve seabed integrity in the Azores.
Biography
Fernando holds a PhD in Geography & Geosciences from the University of St. Andrews (UK) and a Masters in Marine Biology from Lisbon University (PT). His research focuses on Seabed Habitat Mapping, Statistical Modelling, and Marine Biodiversity Cataloguing. He has contributed to marine conservation efforts, including mapping biodiversity and developing management plans for Natura 2000 sites and MPAs. He currently works in France on the automation of marine habitat map production.