Parastichopus regalis and P. tremulus are commonly found in this kind of bottoms
(Salas 1996; García Raso 1996; Abad et al. 2007; Gofas et al. 2011; Hebbeln et al.
2009; de la Torriente et al. 2014, 2018; Ciércoles et al. 2018; Moya-Urbano and
Rueda pers. comm.).
Bathyal muddy bottoms (Fig. 9.22) are probably the most widespread bottom
type in the Alboran Sea and are generally colonized by different cerianthids
(Cerianthus spp., Arachnanthus oligopodus), bamboo coral (Isidella elongata) and
sea pens (Virgularia mirabilis, Kophobelemnon stelliferum, K. cf. leuckarti,
Funiculina quadrangularis), polychaetes (Sabella sp., Spiochaetopterus sp.), molluscs (Abra longicallus, Kelliella miliaris, Nucula sulcata, Cuspidaria spp.,
Aporrhais serresiana, Buccinum humphreysianum, Galeodea rugosa), decapods
(Nephrops norvegicus, Monodaeus couchii, Goneplax rhomboides, Pagurus alatus,
Plesionika spp., Calocaris macandrae), the holothurian Mesothuria intestinalis, the
fragile starfish Hymenodiscus coronatus, the echinoid Brissopsis lyrifera and the
small ophiuroid Ophiocten abyssicolum that sometimes can be the dominant
macrobenthic component (Salas 1996; García Raso 1996; Abad et al. 2007; Hebbeln
et al. 2009; Gofas et al. 2011; Pardo et al. 2011; Ciércoles et al. 2018; Moya-Urbano
and Rueda pers. comm.).
Sea pen communities have also been detected in coarser sandy bottoms of the
Djibouti Banks, the Alboran Ridge and Seco de los Olivos, mainly on areas
characterized by low-medium slopes (Hebbeln et al. 2009; Pardo et al. 2011; de la
Torriente et al. 2018) and in deep slope sedimentary bottoms (Grinyó et al. 2020).
The bamboo coral Isidella elongata is known to occur in the Alboran Sea and has
been documented in several places, such as Seco de los Olivos seamount and
Cabliers and Djibouti Banks (Pardo et al. 2011; de la Torriente et al. 2018) as well
as in deep slope bottoms (Grinyó et al. 2020), with scattered colonies on muddy
bottoms, probably due to trawling activity (see Chap. 10).
Another group that can be abundant in some deep soft bottoms of Alboran Sea are
bryozoans, although with only a few species. Among them, the most common are the
stalked bryozoans Kinetoskias sp., which were thought to have entered from the
Atlantic via the Gibraltar Strait (Harmelin and d’Hondt 1993) but have later been
found further inside the Mediterranean Sea, at the Balearic Islands (Aguilar et al.
2013).
The soft bottoms of the bathyal zone do not fit, even approximately any of the
habitats listed in the EU Habitats Directive. Their sole legal protection derives from
the Art. 4 of the Council Regulation (EC) No 1967/2006 concerning management
measures for the sustainable exploitation of fishery resources in the Mediterranean
Sea (Council of the European Union 2006), which prohibits the use of towed dredges
and trawl nets in fisheries at depths beyond 1000 m.
The bamboo coral Isidella elongata is a critically endangered species, following
IUCN Red List category (Mastrototaro et al. 2017; Otero et al. 2017). Habitats
harbouring Leptometra phalangium, Funiculina quadrangularis and Isidella
elongata and more generally the deep-sea habitats below 1000 m depth are listed
as “Essential Marine Habitats (EMH) of relevance for the management of priority
9 Benthic Fauna of Littoral and Deep-Sea Habitats of the Alboran Sea: A. . .
341
(Salas 1996; García Raso 1996; Abad et al. 2007; Gofas et al. 2011; Hebbeln et al.
2009; de la Torriente et al. 2014, 2018; Ciércoles et al. 2018; Moya-Urbano and
Rueda pers. comm.).
Bathyal muddy bottoms (Fig. 9.22) are probably the most widespread bottom
type in the Alboran Sea and are generally colonized by different cerianthids
(Cerianthus spp., Arachnanthus oligopodus), bamboo coral (Isidella elongata) and
sea pens (Virgularia mirabilis, Kophobelemnon stelliferum, K. cf. leuckarti,
Funiculina quadrangularis), polychaetes (Sabella sp., Spiochaetopterus sp.), molluscs (Abra longicallus, Kelliella miliaris, Nucula sulcata, Cuspidaria spp.,
Aporrhais serresiana, Buccinum humphreysianum, Galeodea rugosa), decapods
(Nephrops norvegicus, Monodaeus couchii, Goneplax rhomboides, Pagurus alatus,
Plesionika spp., Calocaris macandrae), the holothurian Mesothuria intestinalis, the
fragile starfish Hymenodiscus coronatus, the echinoid Brissopsis lyrifera and the
small ophiuroid Ophiocten abyssicolum that sometimes can be the dominant
macrobenthic component (Salas 1996; García Raso 1996; Abad et al. 2007; Hebbeln
et al. 2009; Gofas et al. 2011; Pardo et al. 2011; Ciércoles et al. 2018; Moya-Urbano
and Rueda pers. comm.).
Sea pen communities have also been detected in coarser sandy bottoms of the
Djibouti Banks, the Alboran Ridge and Seco de los Olivos, mainly on areas
characterized by low-medium slopes (Hebbeln et al. 2009; Pardo et al. 2011; de la
Torriente et al. 2018) and in deep slope sedimentary bottoms (Grinyó et al. 2020).
The bamboo coral Isidella elongata is known to occur in the Alboran Sea and has
been documented in several places, such as Seco de los Olivos seamount and
Cabliers and Djibouti Banks (Pardo et al. 2011; de la Torriente et al. 2018) as well
as in deep slope bottoms (Grinyó et al. 2020), with scattered colonies on muddy
bottoms, probably due to trawling activity (see Chap. 10).
Another group that can be abundant in some deep soft bottoms of Alboran Sea are
bryozoans, although with only a few species. Among them, the most common are the
stalked bryozoans Kinetoskias sp., which were thought to have entered from the
Atlantic via the Gibraltar Strait (Harmelin and d’Hondt 1993) but have later been
found further inside the Mediterranean Sea, at the Balearic Islands (Aguilar et al.
2013).
The soft bottoms of the bathyal zone do not fit, even approximately any of the
habitats listed in the EU Habitats Directive. Their sole legal protection derives from
the Art. 4 of the Council Regulation (EC) No 1967/2006 concerning management
measures for the sustainable exploitation of fishery resources in the Mediterranean
Sea (Council of the European Union 2006), which prohibits the use of towed dredges
and trawl nets in fisheries at depths beyond 1000 m.
The bamboo coral Isidella elongata is a critically endangered species, following
IUCN Red List category (Mastrototaro et al. 2017; Otero et al. 2017). Habitats
harbouring Leptometra phalangium, Funiculina quadrangularis and Isidella
elongata and more generally the deep-sea habitats below 1000 m depth are listed
as “Essential Marine Habitats (EMH) of relevance for the management of priority
9 Benthic Fauna of Littoral and Deep-Sea Habitats of the Alboran Sea: A. . .
341