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Abstract In recent years, blooms of the neurotoxic dinoflagellateAlexandrium catenellahave been documented in Pacific Arctic waters, and the paralytic shellfish toxins (PSTs) that this species produces have been detected throughout the food web. These observations have raised significant concerns about the role that harmful algal blooms (HABs) will play in a rapidly changing Arctic. During a research cruise in summer 2022, a massive bloom ofA. catenellawas detected in real time as it was advected through the Bering Strait region. The bloom was exceptional in both spatial scale and density, extending > 600 km latitudinally, reaching concentrations > 174,000 cells L−1, and producing high‐potency PST congeners. Throughout the event, coastal stakeholders in the region were engaged and a multi‐faceted community response was mobilized. This unprecedented bloom highlighted the urgent need for response capabilities to ensure safe utilization of critical marine resources in a region that has little experience with HABs.
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Surface nitrogen conditions associated with bottle uptake measurements during a summer 2022 Alexandrium catenella bloom in the Alaskan Arctic (NRS2022_02S)
In the rapidly changing Arctic ecosystem, the recent emergence of harmful algal blooms (HABs) threatens human and ecosystem health. There is increasing evidence that toxic dinoflagellates of the Alexandrium genus are blooming in the Pacific Arctic Ocean, in dense enough concentrations to necessitate shellfishing closures and to detect toxins in marine mammals that forge in Alaskan waters. Our understanding of the nutrient dynamics that sustain HABs in the Pacific Arctic is severely limited, particularly as these blooms tend to occur in late summer when dissolved inorganic nitrogen is drawn down and limits phytoplankton growth. Dissolved organic nitrogen could prove a critical nitrogen source for HABs in the Pacific Arctic, as it has in other regions. This dataset presents measurements taken on Leg 2 of a research cruise (NRS2022_02S) on the Research Vessel (R/V) Norseman II in Aug-Sep 2022 to characterize the nutrient usage by A. catenella. It includes the nutrients (silicate, phosophate, total dissolved nitrogen, and four dissolved nitrogen substrates), particulate organic carbon and nitrogen, and chlorophyll concentrations associated with the beginning of 13 incubation experiments in which we measured nitrogen uptake rates by the surface biological community. We also include the salinity and temperature measurements from CTD-mounted sensors for water collection from Niskin bottles for each incubation set up. Other associated datasets include: Leah McRaven & Robert Pickart. (2024). Conductivity Temperature Depth (CTD) data from the Norseman II (NRS22-1s and NRS22-2s), as part of the 2022 Origin and Fate of Harmful Algal Blooms in the Warming Chukchi Sea cruise. Arctic Data Center. doi:10.18739/A2B853K56. Evangeline Fachon, Donald M Anderson, Mrunmayee Pathare, Michael Brosnahan, Eric Muhlbach, Kali Horn, Nathaniel Spada, & Anushka Rajagopalan. (2024). Alexandrium catenella planktonic cell abundance and toxicity from the Norseman II (NRS2022_01S and NRS2022_02S), as part of the 2022 Origin and Fate of Harmful Algal Blooms in the Warming Chukchi Sea cruise. Arctic Data Center. doi:10.18739/A2804XM7S. Miguel Goni & Dean Stockwell. (2024). Conductivity-Temperature-Depth (CTD) Bottle Data from the Norseman II cruises (NRS2022_01S and NRS2022_02S) including Particulate Organic Carbon (POC) Particulate Nitrogen (PN), Chlorophyll (Chl), Phaeophytin (Phaeo), and dissolved nutrients (Nitrate, Nitrite, Phosphate, Silicate, and Ammonium) (2022). Arctic Data Center. doi:10.18739/A2M90249T.
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- Award ID(s):
- 2112863
- PAR ID:
- 10555246
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- chlorophyll nitrate ammonia urea dissolved free amino acids
- Format(s):
- Medium: X Other: text/xml
- Location:
- Chukchi and West Beaufort Seas
- Institution:
- Stanford University
- Sponsoring Org:
- National Science Foundation
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