Abstract
Pelagic larval stages (meroplankton) of benthic invertebrates seasonally make up a significant proportion of planktonic communities, as well as determine the distribution of their benthic adult stages, yet are frequently overlooked by both plankton and benthic studies. Within the Arctic, the role of meroplanktonic larvae may be particularly important in regions of inflow from sub-Arctic regions, where they can serve as vectors of advection of temperate species into the Arctic. In this study, we describe the links between the distribution of larvae and adult benthic communities of bivalves, echinoderms, select decapods and cnidarians on the Pacific-influenced Chukchi Sea shelf during August-September in the time period 2004-2015 using traditional morphological and molecular tools to resolve taxonomic diversity. For most taxa, we observed little regional overlap between the distribution of larvae and adults of the same taxon; however, larvae of some organisms (e.g., the burrowing anemone Cerianthus sp., the sand dollar Echinarachnius parma) were only observed near populations of adult organisms. Larval stages of species not commonly observed in the Chukchi Sea benthos were also observed in the plankton; overall, shelf meroplanktonic communities were numerically dominated by larvae of coastal hard-bottom taxa, rather than local soft-bottom shelf species. Our results suggest that most larvae that we observe on the shelf are advected from other areas rather than produced locally, and most likely will not successfully settle to the benthos. Seasonality and distribution of water masses were the most important parameters shaping meroplankton communities. We discuss the implications of changing oceanographic and climatic conditions on the potential of range extensions by temperate species into the Arctic Ocean.
Highlights
The Chukchi Sea is one of two inflow regions of the Arctic, providing the only connection between the temperate Pacific region and high Arctic Ocean (Figure 1)
Most of the flow entering the Chukchi Sea from the Pacific is dominated by a mixture of two currents: the Anadyr Current, originating on the Bering Sea slope and carrying cold, nutrientrich oceanic water, and the Bering Shelf Current, which originates on the Bering Sea shelf and is warmer and lower in nutrients (Coachman and Aagaard, 1975)
We aimed to identify the main driving factors that shape the meroplanktonic communities on the Chukchi sea shelf, anticipating that both local production and advection play important roles in the distribution and the fate of the larvae that we observe in this region
Summary
The Chukchi Sea is one of two inflow regions of the Arctic, providing the only connection between the temperate Pacific region and high Arctic Ocean (Figure 1). Most of the flow entering the Chukchi Sea from the Pacific is dominated by a mixture of two currents: the Anadyr Current, originating on the Bering Sea slope and carrying cold, nutrientrich oceanic water, and the Bering Shelf Current, which originates on the Bering Sea shelf and is warmer and lower in nutrients (Coachman and Aagaard, 1975) These two currents merge as they travel through the Bering Strait, forming Bering SeaAnadyr Water, split into three branches: one exiting north through Herald Canyon; one east of Hanna Shoal and through Barrow Canyon; and one through the Central Channel, which separates Herald Valley and Hanna Shoal (Weingartner et al, 2005; Figure 1). A fourth water mass type, Siberian Coastal Water, is sometimes present in the western Chukchi Sea when the cold, buoyancy driven East-Siberian Coastal Current enters through Long Strait (Weingartner et al, 1999)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
