Hendrix Alicia M, Lefebvre Kathi A, Quakenbush Lori, Bryan Anna, Stimmelmayr Raphaela, Sheffield Gay, Wisswaesser Gabriel, Willis Maryjean L, Bowers Emily K, Kendrick Preston, Frame Elizabeth, Burbacher Thomas, Marcinek David J
Department of Environmental and Occupational Health Sciences University of Washington, Seattle Washington.
Environmental and Fisheries Science Division Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle Washington.
Mar Mamm Sci. 2021 Oct;37(4):1292-1308. doi: 10.1111/mms.12822. Epub 2021 May 3.
Domoic acid (DA) and saxitoxin (STX)-producing algae are present in Alaskan seas, presenting exposure risks to marine mammals that may be increasing due to climate change. To investigate potential increases in exposure risks to four pagophilic ice seal species (, bearded seals; , ringed seals; , spotted seals; and , ribbon seals), this study analyzed samples from 998 seals harvested for subsistence purposes in western and northern Alaska during 2005-2019 for DA and STX. Both toxins were detected in bearded, ringed, and spotted seals, though no clinical signs of acute neurotoxicity were reported in harvested seals. Bearded seals had the highest prevalence of each toxin, followed by ringed seals. Bearded seal stomach content samples from the Bering Sea showed a significant increase in DA prevalence with time (logistic regression, = .004). These findings are consistent with predicted northward expansion of DA-producing algae. A comparison of paired samples taken from the stomachs and colons of 15 seals found that colon content consistently had higher concentrations of both toxins. Collectively, these results suggest that ice seals, particularly bearded seals (benthic foraging specialists), are suitable sentinels for monitoring HAB prevalence in the Pacific Arctic and subarctic.
阿拉斯加海域存在产生软骨藻酸（DA）和石房蛤毒素（STX）的藻类，这给海洋哺乳动物带来了暴露风险，而由于气候变化，这种风险可能正在增加。为了调查四种嗜冰海豹物种（髯海豹；环斑海豹；斑海豹；带纹海豹）暴露风险的潜在增加情况，本研究分析了2005年至2019年期间在阿拉斯加西部和北部为维持生计而捕杀的998只海豹的样本中的DA和STX。在髯海豹、环斑海豹和斑海豹中均检测到了这两种毒素，不过在捕杀的海豹中未报告急性神经毒性的临床症状。髯海豹中每种毒素的患病率最高，其次是环斑海豹。白令海髯海豹胃内容物样本显示，DA患病率随时间显著增加（逻辑回归，P = 0.004）。这些发现与预测的产生DA的藻类向北扩张一致。对15只海豹的胃和结肠采集的配对样本进行比较发现，结肠内容物中两种毒素的浓度始终较高。总体而言，这些结果表明，冰海豹，尤其是髯海豹（底栖觅食专家），是监测太平洋北极和亚北极地区有害藻华患病率的合适哨兵。
