The gulfs that surround Península Valdés (PV), Golfo Nuevo and Golfo San José in Argentina, are important calving grounds for the southern right whale Eubalaena australis. However, high calf mortality events in recent years could be associated with phycotoxin exposure. The present study evaluated the transfer of domoic acid (DA) from Pseudo-nitzschia spp., potential producers of DA, to living and dead right whales via zooplanktonic vectors, while the whales are on their calving ground at PV. Phytoplankton and mesozooplankton (primary prey of the right whales at PV and potential grazers of Pseudo-nitzschia cells) were collected during the 2015 whale season and analyzed for species composition and abundance. DA was measured in plankton and fecal whale samples (collected during whale seasons 2013, 2014 and 2015) using liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). The genus Pseudo-nitzschia was present in both gulfs with abundances ranging from 4.4 × 10² and 4.56 × 10⁵ cell l⁻¹. Pseudo-nitzschia australis had the highest abundance with up to 4.56 × 10⁵ cell l⁻¹. DA in phytoplankton was generally low, with the exception of samples collected during a P. australis bloom. No clear correlation was found between DA in phytoplankton and mesozooplankton samples. The predominance of copepods in mesozooplankton samples indicates that they were the primary vector for the transfer of DA from Pseudo-nitzschia spp. to higher trophic levels. High levels of DA were detected in four whale fecal samples (ranging from 0.30 to 710 μg g⁻¹ dry weight of fecal sample or from 0.05 and 113.6 μg g⁻¹ wet weight assuming a mean water content of 84%). The maximum level of DA detected in fecal samples (710 μg DA g⁻¹ dry weight of fecal sample) is the highest reported in southern right whales to date. The current findings demonstrate for the first time that southern right whales, E. australis, are exposed to DA via copepods as vectors during their calving season in the gulfs of PV.

阿根廷的PenínsulaValdés（PV），Golfo Nuevo和Golfo SanJosé周围的海湾是南部右鲸Eubalaena australis的重要产卵地。但是，近年来小牛死亡率高的事件可能与植物毒素的暴露有关。本研究评估了潜在的生产者假性尼兹菌属物种中的海藻酸（DA）通过浮游动物媒介向活的和死的露脊鲸的转移，而鲸鱼则在PV上产犊。浮游植物和浮游动物（在PV右鲸鱼和潜在食草动物的初级猎物拟菱形藻细胞是在2015年鲸鱼季节收集的，并进行了物种组成和丰度分析。使用液相色谱-串联质谱（LC-MS / MS）测定浮游生物和粪便鲸鱼样品（2013、2014和2015年鲸鱼季节采集）中的DA。拟南芥属存在于两个海湾中，其丰度范围为4.4×10 ²和4.56×10 ⁵细胞l ^-1。拟南芥具有最高的丰度，最高可达4.56×10 ⁵细胞l ^-1。浮游植物的DA一般较低，除了在澳大利亚假单胞菌期间采集的样品外盛开。在浮游植物和中层浮游动物样品中的DA之间没有发现明显的相关性。中足类浮游动物样品中of足类动物的优势表明它们是从拟南芥属植物中转移DA的主要载体。到更高的营养水平。四个鲸粪便样品中检测到（从0.30至710微克克DA的高水平^-1粪便样品的干重或0.05和113.6微克克^-1湿重假设的84％的平均水含量）。粪便样品中检测到的最大DA水平（粪便样品干重为710μgDA g ^-1）是迄今为止在南部的右鲸中报告的最高水平。目前的发现首次证明了南方右鲸E. australis在产犊季节，通过co足类动物作为媒介在DA湾中暴露于DA。