title: Prevalence of algal toxins in Alaskan marine mammals foraging in a changing arctic and subarctic environment.
abstract: Current climate trends resulting in rapid declines in sea ice and increasing water temperatures are likely to expand the northern geographic range and duration of favorable conditions for harmful algal blooms (HABs), making algal toxins a growing concern in Alaskan marine food webs. Two of the most common HAB toxins along the west coast of North America are the neurotoxins domoic acid (DA) and saxitoxin (STX). Over the last 20 years, DA toxicosis has caused significant illness and mortality in marine mammals along the west coast of the USA, but has not been reported to impact marine mammals foraging in Alaskan waters. Saxitoxin, the most potent of the paralytic shellfish poisoning toxins, has been well-documented in shellfish in the Aleutians and Gulf of Alaska for decades and associated with human illnesses and deaths due to consumption of toxic clams. There is little information regarding exposure of Alaskan marine mammals. Here, the spatial patterns and prevalence of DA and STX exposure in Alaskan marine mammals are documented in order to assess health risks to northern populations including those species that are important to the nutritional, cultural, and economic well-being of Alaskan coastal communities. In this study, 905 marine mammals from 13 species were sampled including; humpback whales, bowhead whales, beluga whales, harbor porpoises, northern fur seals, Steller sea lions, harbor seals, ringed seals, bearded seals, spotted seals, ribbon seals, Pacific walruses, and northern sea otters. Domoic acid was detected in all 13 species examined and had the greatest prevalence in bowhead whales (68%) and harbor seals (67%). Saxitoxin was detected in 10 of the 13 species, with the highest prevalence in humpback whales (50%) and bowhead whales (32%). Pacific walruses contained the highest concentrations of both STX and DA, with DA concentrations similar to those detected in California sea lions exhibiting clinical signs of DA toxicosis (seizures) off the coast of Central California, USA. Forty-six individual marine mammals contained detectable concentrations of both toxins emphasizing the potential for combined exposure risks. Additionally, fetuses from a beluga whale, a harbor porpoise and a Steller sea lion contained detectable concentrations of DA documenting maternal toxin transfer in these species. These results provide evidence that HAB toxins are present throughout Alaska waters at levels high enough to be detected in marine mammals and have the potential to impact marine mammal health in the Arctic marine environment.
authors.affiliation: Northwest Fisheries Science Center, NOAA Fisheries, Seattle, WA, USA. Electronic address: Kathi.Lefebvre@noaa.gov.
authors.forename: Kathi A
authors.initials: KA
authors.lastname: Lefebvre
authors.affiliation: Alaska Department of Fish and Game, Arctic Marine Mammal Program, 1300 College Road, Fairbanks, AK, USA.
authors.forename: Lori
authors.initials: L
authors.lastname: Quakenbush
authors.affiliation: Northwest Fisheries Science Center, NOAA Fisheries, Seattle, WA, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Frame
authors.affiliation: Alaska Veterinary Pathology Services (AVPS), 23834 The Clearing Drive, Eagle River, AK, USA.
authors.forename: Kathy Burek
authors.initials: KB
authors.lastname: Huntington
authors.affiliation: University of Alaska Fairbanks, Alaska Sea Grant, Marine Advisory Program, PO Box 400, Nome, AK, USA.
authors.forename: Gay
authors.initials: G
authors.lastname: Sheffield
authors.affiliation: North Slope Borough Department of Wildlife Management, PO Box 69, Barrow, AK, USA.
authors.forename: Raphaela
authors.initials: R
authors.lastname: Stimmelmayr
authors.affiliation: Alaska Department of Fish and Game, Arctic Marine Mammal Program, 1300 College Road, Fairbanks, AK, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Bryan
authors.affiliation: Northwest Fisheries Science Center, NOAA Fisheries, Seattle, WA, USA.
authors.forename: Preston
authors.initials: P
authors.lastname: Kendrick
authors.affiliation: Marine Mammal Laboratory, Alaska Fisheries Science Center, NOAA, Seattle, WA, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Ziel
authors.affiliation: One Health Institute, School of Veterinary Medicine, University of California, Davis, CA, USA.
authors.forename: Tracey
authors.initials: T
authors.lastname: Goldstein
authors.affiliation: U.S. Fish and Wildlife Service, Marine Mammals Management, 1011 East Tudor Rd., Anchorage, AK, USA.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Snyder
authors.affiliation: Marine Mammal Laboratory, Alaska Fisheries Science Center, NOAA, Seattle, WA, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Gelatt
authors.affiliation: The Marine Mammal Center, 2000 Bunker Road, Fort Cronkhite, Sausalito, CA, USA.
authors.forename: Frances
authors.initials: F
authors.lastname: Gulland
authors.affiliation: Marine Mammal Laboratory, Alaska Fisheries Science Center, NOAA, Seattle, WA, USA.
authors.forename: Bobette
authors.initials: B
authors.lastname: Dickerson
authors.affiliation: U.S. Fish and Wildlife Service, Marine Mammals Management, 1011 East Tudor Rd., Anchorage, AK, USA.
authors.forename: Verena
authors.initials: V
authors.lastname: Gill
mesh_terms: D000413:Alaska; D000818:Animals; D059001:Aquatic Organisms / Q000378:metabolism*; D001110:Arctic Regions; D002140:California; D010872:Caniformia / Q000378:metabolism*; D002591:Cetacea / Q000378:metabolism*; D004784:Environmental Monitoring; D008387:Marine Toxins / Q000032:analysis*; D015995:Prevalence
chemical_list: D008387:Marine Toxins