title: Large-Scale Spatio-Temporal Patterns of Mediterranean Cephalopod Diversity.
abstract: Species diversity is widely recognized as an important trait of ecosystems' functioning and resilience. Understanding the causes of diversity patterns and their interaction with the environmental conditions is essential in order to effectively assess and preserve existing diversity. While diversity patterns of most recurrent groups such as fish are commonly studied, other important taxa such as cephalopods have received less attention. In this work we present spatio-temporal trends of cephalopod diversity across the entire Mediterranean Sea during the last 19 years, analysing data from the annual bottom trawl survey MEDITS conducted by 5 different Mediterranean countries using standardized gears and sampling protocols. The influence of local and regional environmental variability in different Mediterranean regions is analysed applying generalized additive models, using species richness and the Shannon Wiener index as diversity descriptors. While the western basin showed a high diversity, our analyses do not support a steady eastward decrease of diversity as proposed in some previous studies. Instead, high Shannon diversity was also found in the Adriatic and Aegean Seas, and high species richness in the eastern Ionian Sea. Overall diversity did not show any consistent trend over the last two decades. Except in the Adriatic Sea, diversity showed a hump-shaped trend with depth in all regions, being highest between 200-400 m depth. Our results indicate that high Chlorophyll a concentrations and warmer temperatures seem to enhance species diversity, and the influence of these parameters is stronger for richness than for Shannon diversity.
authors.affiliation: Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Muelle de Poniente, s/n, Apdo. 291, 07015 Palma de Mallorca, Spain.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Keller
authors.affiliation: SLU Swedish University of Agricultural Sciences, Department of Aquatic Resources, Lysekil, Sweden.
authors.forename: Valerio
authors.initials: V
authors.lastname: Bartolino
authors.affiliation: Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Muelle de Poniente, s/n, Apdo. 291, 07015 Palma de Mallorca, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Hidalgo
authors.affiliation: COISPA-Tecnologia & Ricerca, Stazione Sperimentale per lo Studio delle Risorse del Mare, Bari, Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Bitetto
authors.affiliation: COISPA-Tecnologia & Ricerca, Stazione Sperimentale per lo Studio delle Risorse del Mare, Bari, Italy.
authors.forename: Loredana
authors.initials: L
authors.lastname: Casciaro
authors.affiliation: Dipartemento di Scienze della Vita e dell'Ambiente, Università di Cagliari, Cagliari, Italy IEO.
authors.forename: Danila
authors.initials: D
authors.lastname: Cuccu
authors.affiliation: Centro Oceanográfico de Murcia, San Pedro del Pinatar, Murcia, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Esteban
authors.affiliation: IEO, Centro Oceanográfico de Malaga, Fuengirola, Málaga, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Garcia
authors.affiliation: IAMC-Coastal Marine Environment Insitute-CNR, Mazara del Vallo (TP), Italy.
authors.forename: Germana
authors.initials: G
authors.lastname: Garofalo
authors.affiliation: DFMR-Department of Fisheries and Marine Research, Ministry of Agriculture, Rural Development and Environment, Nicosia, Cyprus.
authors.forename: Marios
authors.initials: M
authors.lastname: Josephides
authors.affiliation: Ifremer, Institut Français de Recherche pour l'Exploitation de la mer, UMR 212 Ecosystèmes Marins Exploités (EME), Sète, France.
authors.forename: Angelique
authors.initials: A
authors.lastname: Jadaud
authors.affiliation: HCMR, Hellenic Centre of Marine Research, Athens, Greece.
authors.forename: Evgenia
authors.initials: E
authors.lastname: Lefkaditou
authors.affiliation: University of Bari Aldo Moro-Department of Biology, Bari, Italy.
authors.forename: Porzia
authors.initials: P
authors.lastname: Maiorano
authors.affiliation: Laboratorio Biologia Marina e Pesca, Università di Bologna, Fano (PS), Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Manfredi
authors.affiliation: Fishery Research Institute of Slovenia, Ljubljana-Smartno, Slovenia.
authors.forename: Bojan
authors.initials: B
authors.lastname: Marceta
authors.affiliation: Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Muelle de Poniente, s/n, Apdo. 291, 07015 Palma de Mallorca, Spain.
authors.forename: Enric
authors.initials: E
authors.lastname: Massutí
authors.affiliation: Ministry for Sustainable Development, Department of Fisheries and Aquaculture, Marsa, Malta.
authors.forename: Reno
authors.initials: R
authors.lastname: Micallef
authors.affiliation: HCMR, Hellenic Centre of Marine Research, Heraklion, Crete, Greece.
authors.forename: Panagiota
authors.initials: P
authors.lastname: Peristeraki
authors.affiliation: SIBM, Società Italiana di Biologia Marina, Genova and DISTAV, Università di Genova, Genova, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Relini
authors.affiliation: CIBM-Centro Interuniversitario di Biologia Marina ed Ecologia Applicata, Livorno, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Sartor
authors.affiliation: COISPA-Tecnologia & Ricerca, Stazione Sperimentale per lo Studio delle Risorse del Mare, Bari, Italy.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Spedicato
authors.affiliation: HCMR, Hellenic Centre of Marine Research, Heraklion, Crete, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Tserpes
authors.affiliation: Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Muelle de Poniente, s/n, Apdo. 291, 07015 Palma de Mallorca, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Quetglas
mesh_terms: D000818:Animals; D044822:Biodiversity; D049830:Cephalopoda / Q000502:physiology*; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D005843:Geography; D019083:Mediterranean Region; D008962:Models, Theoretical; D013045:Species Specificity; D013696:Temperature; D013997:Time Factors
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A