Mercury biomagnification in an Antarctic food web of the Antarctic Peninsula

Sex‐specific mercury levels in skin samples of southern elephant seals (Mirounga leonina) at Isla 25 de Mayo (King George Island), Antarctic Peninsula

“…This study provides the first description of sex‐specific THg concentrations in hairless skin of SES from molting individuals on Isla 25 de Mayo/King George Island. Mean THg concentrations are similar to those reported previously for SES hair from the South Shetland Islands ( M = 1,654, SD = 1,390 ng/g dw, n = 15; Matias et al, 2022), and below to those reported for lanugo from pups that reflected THg transferred from their mothers ( M = 5,600, SD = 300 ng/g dw, n = 35; Kehrig et al, 2022), and adult liver samples ( M = 25,680 ng/g dw, n = 2; Cipro et al, 2017). They were, however, higher than fat ( M = 180 ng/g ww, n = 2; de Moreno et al, 1997), muscle (613 ng/g dw, n = 1; M = 180 ng/g ww, n = 2; Cipro et al, 2017; de Moreno et al, 1997), and skin ( M = 120 ng/g ww, n = 2; de Moreno et al, 1997).…”

“…In Antarctica, Hg has been reported in sediments, bottom water, column water, krill, and other local fauna and flora (e.g., Angel-Romero et al, 2018;Bargagli, 2016;Bengston et al, 2021;Carravieri et al, 2020;Cipro et al, 2017;Cossa et al, 2011;de Moreno et al, 1997;dos Santos et al, 2006;Kehrig et al, 2022;Matias et al, 2022;Seco et al, 2019Seco et al, , 2020aSeco et al, , 2020bSontag et al, 2019). Katabatic winds favor the transport of Hg from the mainland to coastal areas and sea-ice, where Hg is then released into sediments and deeper waters, and then spreads into the water column during upwelling events (Bargagli, 2016;Cossa et al, 2011;Liu et al, 2019).…”

“…During these long‐distance migrations, SES are exposed to pollutants, such as mercury (Hg), through their diet. Of particular concern is the common organic Hg form, called methylmercury (MeHg), which has a high toxicity, biomagnifies along trophic webs including that of the Southern Ocean (e.g., Matias et al, 2022), and bioaccumulates in long‐lived top predators. Therefore, the United Nations Environment Program through the goals of the Minamata Convention on Hg has proposed to implement a worldwide biomonitoring network (Bengston et al, 2021; Evers & Sunderland, 2019).…”

“…Despite the potential role of SES as Hg bioindicators in Antarctica, little is still known about their exposure. For instance, in the South Shetland Islands where breeding and molting colonies are established, only four studies have assessed current Hg accumulation in SES: two at Isla 25 de Mayo/King George Island (tissues: liver and muscle; Cipro et al, 2017; muscle, skin; de Moreno et al, 1997), one at Livingston Island (hair; Matias et al, 2022), and one in recently weaned pups from Elephant Island (lanugo; Kehrig et al, 2022).…”

“…For this reason, tissue samples obtained by minimally invasive methods should be more effective for assessing Hg contamination of SES. Tissues like hair and blood have been successfully used for this assessment in the northern elephant seal ( Mirounga a ngustirostris ; e.g., Cossaboon et al, 2015; Peterson et al, 2015) and in the SES (e.g., Kehrig et al, 2022; Matias et al, 2022). Skin, obtained from minimally invasive remote biopsy sampling, has also been shown to provide accurate Hg concentrations from other free‐ranging marine mammal species (e.g., Aubail et al, 2013; Cáceres‐Saez et al, 2015; Fontaine et al, 2015).…”