Improving Scientific Knowledge of Mallorca Channel Seamounts (Western Mediterranean) within the Framework of Natura 2000 Network

Abstract

The scientific exploration of Mallorca Channel seamounts (western Mediterranean) is improving the knowledge of the Ses Olives (SO), Ausias March (AM), and Emile Baudot (EB) seamounts for their inclusion in the Natura 2000 network. The aims are to map and characterize benthic species and habitats by means of a geological and biological multidisciplinary approach: high-resolution acoustics, sediment and rock dredges, beam trawl, bottom trawl, and underwater imagery. Among the seamounts, 15 different morphological features were differentiated, highlighting the presence of 4000 pockmarks, which are seafloor rounded depressions indicators of focused fluid flow escapes, usually gas and/or water, from beneath the seabed sediments. So far, a total of 547 species or taxa have been inventoried, with sponges, fishes, mollusks, and crustaceans the most diverse groups including new taxa and new geographical records. Up to 29 categories of benthic habitats have been found, highlighting those included in the Habitats Directive: maërl beds on the summits of AM and EB, pockmarks around the seamounts and coral reefs in their rocky escarpments as well as fields of Isidella elongata on sedimentary bathyal bottoms. Trawling is the main demersal fishery developed around SO and AM, which are targeted to deep water crustaceans: Parapenaeus longirostris, Nephrops norvegicus, and Aristeus antennatus. This study provides scientific information for the proposal of the Mallorca Channel seamounts as a Site of Community Importance and for its final declaration as a Special Area of Conservation.

The Punta de la Mona Rhodolith Bed: Shallow-Water Mediterranean Rhodoliths (Almuñecar, Granada, Southern Spain)

“…The Punta de la Mona rhodolith bed is unique due to the scarcity of this kind of formation in the Alborán Sea, and its shallow depth range, contrasting with the generally deeper depth distribution of rhodolith beds in the Mediterranean (Basso et al, 2017). In this sea, the majority of rhodolith beds occur at 30-75 m, although in oligotrophic clear waters may reach depths close to 150 m, such as in the Balearic Islands (Massutí et al, 2022). Beds shallower than 25 m are scarce, although they occur from 2 m depth in Tunisia (CAR/ASP-PNUE/PAM, 2011), at 9-10 m in Israel (Ramos-Esplá et al, 2012), and in the Apulian shelf in southern Italy (Chimienti et al, 2020).…”

Distolambrus maltzami (Miers, 1881) (Brachyura: Parthenopidae) with observed and modelled distribution in the North-east Atlantic

“…Individuals may get recorded sporadically when they are captured, for example when the mesh liner is restricted by the catch such as turf fauna. For example, a thorough sort of megabenthos collected using a 5 mm mesh liner recovered 43 individuals of D. maltzami from across 85 trawls of the Balearic Islands (Massutí et al ., 2021). Additionally, there is comparatively less sampling effort on the shelf edge habitats where it occurs, compared with shallower areas of the inner continental shelf.…”

“…Mediterranean: Málaga, Southern Spain (García-Raso, 1984; García-Raso et al ., 1987); Alboran Sea, off Morocco (García-Raso, 1984); Habibas Islands, off Algeria (Délye, 1957); Balearic Sea (De Miranda y Rivera, 1933); Balearic Islands (Garcia & Gràcia, 1996; Massutí et al ., 2021); Banyuls (Noël, 1983); Cap Sicié (Milne-Edwards & Bouvier, 1900); Gulf of Naples (Moncharmont, 1981); Straits of Sicily (Massi et al ., 2010); Adriatic Sea (Pesta, 1918; Števčić, 1990); Ionian Sea (Pastore, 1972); Aegean Sea (Koukouras et al ., 1992; Voultsiadou et al ., 2011; Santin et al ., 2021).…”

“…Most of the tropical and subtropical records from West Africa have tended to be from relatively shallow waters, from the sublittoral to 100 m (Manning & Holthuis, 1981), but sometimes as deep as 347 m, off the Cape Verde Islands (Milne-Edwards & Bouvier, 1900). Recent records give a more extensive depth range of 22–550 m (De Matos-Pita et al ., 2017) with a trend for relatively shallow <100 m depth records (Massi et al ., 2010; Santin et al ., 2021) but also includes specimens from as deep as 412 m (Massutí et al ., 2021). This crab has been reported from a range of seabed types, including shell debris, shelly sand, sand, muddy sand, mud, calcareous algae, coral and rock (Pesta, 1918; Manning & Holthuis, 1981).…”

Iberfault 2022. IV Reunión Ibérica sobre Fallas Activas y Paleosismología. Volumen de resúmenes, Teruel, 7 al 10 de septiembre de 2022 ; 1ª ed.

“…La franja costera entre Adra y Almería, es una de las zonas con mayor peligrosidad sísmica en España (IGN-UPM, 2012). Se atribuye mayormente a la reciente actividad de fallas NNW-SSE a NW-SE, con componente normal-dextral, abundantes en la zona (Martínez Díaz, 2000;Marín-Lechado et al, 2005;. El terremoto de 1804 (IEMS=VII-IX; Mw 6.4-6.6), con epicentro en Dalías, destruyó las poblaciones de Dalías y Berja, provocando la muerte de unas 175 personas (Murphy, 2019).…”