title: Spatial scale, means and gradients of hydrographic variables define pelagic seascapes of bluefin and bullet tuna spawning distribution.
abstract: Seascape ecology is an emerging discipline focused on understanding how features of the marine habitat influence the spatial distribution of marine species. However, there is still a gap in the development of concepts and techniques for its application in the marine pelagic realm, where there are no clear boundaries delimitating habitats. Here we demonstrate that pelagic seascape metrics defined as a combination of hydrographic variables and their spatial gradients calculated at an appropriate spatial scale, improve our ability to model pelagic fish distribution. We apply the analysis to study the spawning locations of two tuna species: Atlantic bluefin and bullet tuna. These two species represent a gradient in life history strategies. Bluefin tuna has a large body size and is a long-distant migrant, while bullet tuna has a small body size and lives year-round in coastal waters within the Mediterranean Sea. The results show that the models performance incorporating the proposed seascape metrics increases significantly when compared with models that do not consider these metrics. This improvement is more important for Atlantic bluefin, whose spawning ecology is dependent on the local oceanographic scenario, than it is for bullet tuna, which is less influenced by the hydrographic conditions. Our study advances our understanding of how species perceive their habitat and confirms that the spatial scale at which the seascape metrics provide information is related to the spawning ecology and life history strategy of each species.
authors.affiliation: Balearic Islands Coastal Observing and Forecasting System (SOCIB), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Alvarez-Berastegui
authors.affiliation: College of Earth, Ocean, and Atmospheric Sciences (CEOAS), Oregon State University, Corvallis, Oregon, United States of America.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Ciannelli
authors.affiliation: Instituto Español de Oceanografía - Centre Oceanogràfic de les Balears (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Aparicio-Gonzalez
authors.affiliation: Instituto Español de Oceanografía - Centre Oceanogràfic de les Balears (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Reglero
authors.affiliation: Instituto Español de Oceanografía - Centre Oceanogràfic de les Balears (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Hidalgo
authors.affiliation: Instituto Español de Oceanografía - Centre Oceanogràfic de les Balears (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: López-Jurado
authors.affiliation: Balearic Islands Coastal Observing and Forecasting System (SOCIB), Palma de Mallorca, Balearic Islands, Spain; Institute for Advanced Studies (IMEDEA), Consejo Superior de Investigaciones Científicas (CSIC) and the University of the Balearic Islands (UIB). Esporles, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Tintoré
authors.affiliation: Instituto Español de Oceanografía - Centre Oceanogràfic de les Balears (COB-IEO), Palma de Mallorca, Balearic Islands, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Alemany
mesh_terms: D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D062312:Islands; D008522:Mediterranean Sea; D008962:Models, Theoretical; D011157:Population Dynamics; D054712:Salinity; D012623:Seawater; D062206:Spatial Analysis; D014413:Tuna