Effects of mesoscale structures on the distribution of cephalopod paralarvae in the Gulf of California and adjacent Pacific. (January 2018)

• Record Type: Journal Article
• Authors: Ruvalcaba-Aroche, Erick D.; Sánchez-Velasco, Laura; Beier, Emilio; Godínez, Victor M.; Barton, Eric D.; Pacheco, Ma. Rocío
• Is Part Of: Deep sea research. Volume 131(2018)
• Page Start: 62
• Page End: 74
• Publication Date: 2018-01
• Subjects: Paralarvae -- Cephalopods -- "SD complex" -- Mesoscale structures -- Water masses -- Gulf of California -- Eastern tropical-subtropical Pacific; Oceanography -- Periodicals; Océanographie -- Périodiques; 551.4605
• DOI: 10.1016/j.dsr.2017.11.005
• Languages: English
• ISSNs: 0967-0637

Abstract

Abstract: Vertical distribution of the cephalopod paralarvae was investigated in relation to a system of two cyclonic and three anticyclonic eddies in the southern Gulf of California and a front in the adjacent Pacific Ocean. Results showed that the preferential habitat for the Sthenoteuthis oualaniensis – Dosidicus gigas "SD-complex" in both regions was the oxygenated surface mixed layer and the thermocline. The highest abundances occurred in of one of the anticyclonic eddies and a frontal zone, which are convergent structures. Enoploteuthid and Pyroteuthid paralarvae both displayed their highest abundances in the thermocline. Pyroteuthids dominated in the cyclonic eddy whereas Enoploteuthidae were less evident in the eddy system. Pyroteuthids were observed on the western (California Current) side of the frontal zone, and Enoploteuthids on its eastern (Gulf of California) side. The octopods and the complex of Ommastrephes-Eucleoteuthis-Hyaloteuthis paralarvae were present below the thermocline. Both groups had a scarce presence in the eddy system and high abundance near the frontal zone. The octopods abounded on the eastern side in association with the low dissolved oxygen concentrations (< 44 µmol kg −1 ) of Subtropical-Subsurface Water; the complex on the western front side was immersed in California Current Water. It may be concluded that the spawning and early stages of development of these cephalopod groups are associated with particular mesoscale structures of the water masses. For example, the "SD complex" inhabits the surface water masses, preferentially in convergence zones generated by mesoscale activity. Highlights: Preferential nursery habitat of most cephalopods is the thermocline. Preferential nursery habitat of SD-complex ommastrephid squid paralarvae is in convergent structures. Octopods paralarvae successfully inhabit both hypoxic and suboxic waters.