title: Vertical migrations of a deep-sea fish and its prey.
abstract: It has been speculated that some deep-sea fishes can display large vertical migrations and likely doing so to explore the full suite of benthopelagic food resources, especially the pelagic organisms of the deep scattering layer (DSL). This would help explain the success of fishes residing at seamounts and the increased biodiversity found in these features of the open ocean. We combined active plus passive acoustic telemetry of blackspot seabream with in situ environmental and biological (backscattering) data collection at a seamount to verify if its behaviour is dominated by vertical movements as a response to temporal changes in environmental conditions and pelagic prey availability. We found that seabream extensively migrate up and down the water column, that these patterns are cyclic both in short-term (tidal, diel) as well as long-term (seasonal) scales, and that they partially match the availability of potential DSL prey components. Furthermore, the emerging pattern points to a more complex spatial behaviour than previously anticipated, suggesting a seasonal switch in the diel behaviour mode (benthic vs. pelagic) of seabream, which may reflect an adaptation to differences in prey availability. This study is the first to document the fine scale three-dimensional behaviour of a deep-sea fish residing at seamounts.
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; LARSyS - Laboratory of Robotics and Systems in Engineering and Science, Lisboa, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Afonso
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; MARICE, Faculty of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland.
authors.forename: Niall
authors.initials: N
authors.lastname: McGinty
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; LARSyS - Laboratory of Robotics and Systems in Engineering and Science, Lisboa, Portugal.
authors.forename: Gonçalo
authors.initials: G
authors.lastname: Graça
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; LARSyS - Laboratory of Robotics and Systems in Engineering and Science, Lisboa, Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Fontes
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; LARSyS - Laboratory of Robotics and Systems in Engineering and Science, Lisboa, Portugal.
authors.forename: Mónica
authors.initials: M
authors.lastname: Inácio
authors.affiliation: IMR - Institute of Marine Research, Bergen, Norway.
authors.forename: Atle
authors.initials: A
authors.lastname: Totland
authors.affiliation: IMAR - Institute of Marine Research at the University of the Azores, Dept. of Oceanography and Fisheries, Horta, Portugal; LARSyS - Laboratory of Robotics and Systems in Engineering and Science, Lisboa, Portugal.
authors.forename: Gui
authors.initials: G
authors.lastname: Menezes
mesh_terms: D025041:Animal Migration; D000818:Animals; D005399:Fishes; D009068:Movement; D009792:Oceans and Seas; D012621:Seasons; D013686:Telemetry