Publication Date:
2022-05-26
Description:
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Klevjer, T., Melle, W., Knutsen, T., Strand, E., Korneliussen, R., Dupont, N., Salvanes, A. G. V., & Wiebe, P. H. Micronekton biomass distribution, improved estimates across four north Atlantic basins. Deep-Sea Research Part II: Topical Studies in Oceanography, 180, (2020): 104691, doi:10.1016/j.dsr2.2019.104691.
Description:
Distribution of micronekton was investigated during early summer of 2013, using data from a cruise covering the central parts of four north Atlantic basins, the Norwegian Sea (NS), Iceland Sea (ICS), Irminger Sea (IRS), and Labrador Sea (LS). Continuous underway acoustics mapped vertical and horizontal distributions, and trawl sampling provided data on biomass and taxonomic composition. The hull mounted acoustics and trawl catches suggested that, among the four basins, biomass of epipelagic, larger nektonic species (〉20 cm length) during the cruise was highest in the NS and ICS basins, while mesopelagic non-gelatinous micronekton biomass peaked in the IRS and LS basins. Biomass of Scyphozoa was also about 1 order of magnitude higher in IRS and LS compared to ICS and NS. In ICS and NS, crustaceans made up about 50% of total non-gelatinous micronekton biomass, with fish making up less than 20% of total biomass. In contrast, fish constituted more than 60% of non-gelatinous biomass of catches in IRS and LS. In catches from ICS and NS the myctophid Benthosema glaciale dominated the catches, whereas bathylagids, gonostomatids, barracudinas and stomiids contributed to the high biomass densities of fish in IRS and LS. In addition to the differences in biomass between the basins, the acoustic measurements suggested gradients within the north-eastern basins, and large differences in vertical distribution of biomass between the basins during the cruise.
Description:
The detailed comments of two anonymous reviewers improved this paper. We gratefully acknowledge the cooperative effort and support provided by the Captains and Crew of the RV G.O. Sars during the six-week trans-Atlantic expedition. We are sincerely thankful for the financial support of the Institute of Marine Research that made the mission with G.O. Sars possible. The EU is thanked for support through EuroBasin (Integrated Project on Basin Scale Analysis, Synthesis and Integration), funded by Framework Programme 7, Contract 264933. The Research Council of Norway is thanked for the financial support through “Harvesting marine cold-water plankton species - abundance estimation and stock assessment” - (Harvest II, RCN 203871). The work is also a contribution to the Norwegian Sea Ecosystem Programme at IMR.
Repository Name:
Woods Hole Open Access Server
Type:
Article
