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Distribution and Prevalence of Harmful Algal Blooms in Arctic Waters

Tracking the impact of harmful algal blooms in the Arctic

The Harmful Algal Bloom (HAB) Project is dedicated to examining the prevalence of different HAB species in Arctic seas using sediment and water samples collected on research cruises in the Bering, Beaufort, and Chukchi seas. Partnering collaborators were contacted to collect HAB samples from other areas on different cruises.

The resulting large cyst bed of Alexandrium catenalla found between cruise-collected samples is unparalleled compared to previous years, leading to the concern of warming waters and additional spreading of these organisms to different areas within and outside studied areas. Future research includes conceptual modeling and categorizing the spread of HAB taxa, as well as incorporating an Imaging Flow Cytobot (IFCB) within monitoring activities.

Alaskan (2018–2020) and Gulf of Maine (2004–2012) Alexandrium catenella cyst abundance in surface sediments, depicted on the same scale (Albers Equal-Area Conic projection). Sites visited across multiple years were averaged to create these composite maps.

Don Anderson

Primary Investigator

Project Institution: Woods Hole Oceanographic Institution 

Partnerships: NSF

Award Period: 01 October 2021 – 30 September 2022

Vessels Information: R/V Norseman II, R/V Sikuliaq, Cruises of Opportunity (during the 2022 Bering Arctic Subarctic Integrated Survey and the Northern Bering Sea Survey)

What Are Harmful Algal Blooms?

Due to climate change, many aquatic microorganisms are flourishing from high levels of nutrients and warmer waters, causing for algal blooms to occur more frequently in the Arctic sea. Although most species are harmless, two harmful algal bloom (HAB) species are posing large threats to human, ocean, and ecosystem health.

One is a toxic dinoflagellate called Alexandrium catenella, responsible for infecting shellfish that cause paralytic shellfish poisoning (PSP). The second is a toxic diatom called Pseudo-nitzschia, responsible for amnesic shellfish poisoning (ASP). This is concerning for Alaskan sea regions, as extremely high concentrations of dormant A. catenella have been documented in samples from the Chukchi Sea, alluding that HAB events have already begun to affect the stability of local resources.

Alexandrium catenella
Satellite image of Alexandrium catenalla algal bloom in the Bering Sea.
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Data Access

About The Datasets 

Offshore sampling for harmful algal bloom (HAB) species was conducted in two back-to-back research cruises aboard the R/V Norseman II (July 19, 2022 – August 15,  2022, 28 days and August 17, 2022 to Sept. 6, 2022, 21 days). 

Along with collecting water and sediment samples, an Imaging FlowCytobot (IFCB) was configured to collect phytoplankton imagery along the cruise track. Net tows and benthic invertebrate samples were also collected to measure levels of the food web.

By The Numbers

Between both cruises, 120 sediment grabs were collected, 47 net tows were deployed, and water samples were collected across multiple depths at 191 locations. Additional sediment and water samples were collected aboard cruises of opportunity, including the 2022 Bering  Arctic Subarctic Integrated Survey (BASIS, 8/12/22 – 9/11/22) and the Northern Bering Sea  Survey (NBS, 8/27/22 – 9/20/22).  

2018 Healy Cruise Data

2019 Healy Cruise Data

Alexandrium catenella planktonic cell distribution in the Alaskan Arctic (2018-2019)

Alexandrium catenella resting cyst distribution in the Alaskan Arctic (2018-2019)

Imaging FlowCytobot (IFCB) Data

(a) An Imaging FlowCytobot (IFCB). Image credit: Michael Brosnahan, WHOI (b) Examples of phytoplankton imaging data that the instrument produces. A single water sample collected from shipboard underway seawater in the Chukchi Sea during an August 2018 cruise contained Alexandrium (red boxes) and Pseudo-nitzschia (blue boxes). (c) Post-processing of IFCB imagery classifies cells by type, allowing easy identification and quantification of HAB cells, including Alexandrium, Pseudo-nitzschia, Karenia, and Dinophysis.

Featured Publication

Harmful algal blooms in the Alaskan Arctic: an emerging threat as oceans warm

March 1, 2023

Donald M. Anderson Evangeline FachonKatherine HubbardKathi A. LefebvrePeigen LinRobert PickartMindy RichlenGay Sheffield, and Caroline Van Hemert 

Harmful algal blooms (HABs) present an emerging threat to human and ecosystem health in the Alaskan Arctic. Two HAB toxins are of concern in the region: saxitoxins (STXs), a family of compounds produced by the dinoflagellate Alexandrium catenella, and domoic acid (DA), produced by multiple species in the diatom genus Pseudo-nitzschia. These potent neurotoxins cause paralytic and amnesic shellfish poisoning, respectively, in humans, and can accumulate in marine organisms through food web transfer, causing illness and mortality among a suite of wildlife species. 

Publications & References

Anderson, D.M., E. Fachon, K. Hubbard, K.A. Lefebvre, P. Lin, R.S. Pickart, M. Richlen, G.Sheffield, C. Van Hemert. 2022. Harmful Algal Blooms in the Alaskan Arctic: An Emerging Threat as Oceans Warm. Oceanography (35).
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Dai, Y., Yang, S., Zhao, D., Hu, C., Xu, W., Anderson, D.M., et al., 2023. Coastal phytoplankton blooms expand and intensify in the 21st century. Nature 615, p. 280–284. 
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Erdner, D.L., Richlen, M.R., McCauley, L.A.R., Anderson, D.M., 2011. Diversity and Dynamics  of a Widespread Bloom of the Toxic Dinoflagellate Alexandrium fundyense. PloS one 6(7),  e22965.
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Harmful Algal Bloom Task Force. 2022.  Progress and Recommendations Regarding Red Tide (Karenia brevis) Blooms.  St. Petersburg, FL: Florida Fish and Wildlife Conservation Commission. Consensus document #2, December 2021.
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Hubbard, K.A., Rocap, G. and Armbrust, E., 2008. Inter-and intraspecific community structure  within the diatom genus Pseudo-nitzschia (Bacillariophyceae). Journal of Phycology, 44(3),  pp.637-649. 
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Hubbard, K.A., Olson, C.H. and Armbrust, E.V., 2014. Molecular characterization of Pseudo nitzschia community structure and species ecology in a hydrographically complex estuarine  system (Puget Sound, Washington, USA). Marine Ecology Progress Series, 507, p.39. 
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Hubbard KA, Villac MC, Chadwick C, DeSmidt AA, Flewelling L, et al., 2023. Spatiotemporal transitions in Pseudo-nitzschia species assemblages and domoic acid along the Alaska coast. PLOS ONE 18(3): e0282794. 
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Lefebvre, K.A., Fachon, E., Bowers, E.K., Kimmel, D.G., Snyder, J.A., Stimmelmayr, R., Grebmeier, J.M., Kibler, S., Hardison, D.R., Anderson, D.M. and Kulis, D., 2022. Paralytic shellfish toxins in Alaskan Arctic food webs during the anomalously warm ocean conditions of 2019 and estimated toxin doses to Pacific walruses and bowhead whales. Harmful Algae, 114, p.102205.
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Richlen, M.L., Erdner, D.L., McCauley, L.A.R., Libera, K., Anderson, D.M., 2012. Extensive  genetic diversity and rapid population differentiation during blooms of Alexandrium fundyense  (Dinophyceae) in an isolated salt pond on Cape Cod, MA, USA. Ecology and Evolution, 2(10):  2583-2594
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10/24/22, Fachon, E., Kulis, D., Richlen, M., Uva, V. Lefebvre, K., Anderson, D., Toxin profiles  of A. catenella isolates and bloom populations from the Northern Bering and Chukchi Seas, 11th  U.S. Symposium on Harmful Algae, Albany, New York, poster & talk.

10/24/22, Spada, Nathaniel, Anderson, D.M., Kulis, D., Uva, Victoria, Long-term preservation  of Alexandrium catenella cells for FISH hybridization , 11th U.S. Symposium on Harmful  Algae, Albany, New York, poster and talk

10/24/22, Don Anderson, Evie Fachon, Robert Pickart, Alexis Fischer, Dave Kulis, Nate Spada,  Kali Horn, Mike Brosnahan, Mindy Richlen, Peigen Lin, Leah McRaven, Kate Hubbard, Kathi  LeFebvre, Large-scale Alexandrium catenella blooms in the Alaskan Arctic: new observations  and analyses, 11th U.S. Symposium on Harmful Algae, Albany, New York

10/24/22, Lefebvre, K.A., Anderson, D. M., Fachon, E., Bowers, E., et al., , Algal toxins in  Arctic food webs and estimated doses to Pacific walruses and bowhead whales, 11th U.S.  Symposium on Harmful Algae, Albany, New York

10/20/22, Anderson, D.M., Toxic algae blooms in the Arctic, Arctic Clash: Geopolitics and the  Environment, NSF-USC Workshop on Arctic Climate Change and Security, University of Southern California DC Center

9/16/22, Anderson, D.M., Harmful Algae in Western Alaska: Summer 2022 Bloom Event, Strait. Science Series, University of Alaska Fairbanks (online)
Link To Recording

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