Researchers discovered that seals adding to the toxic mercury levels in coastal waters may just be further mounting on the pollution levels and placing certain animals at risk, in spite of the fact that large fish, and other mammals naturally accumulate the substance themselves.
However, scientists examined the high levels of methyl mercury gathering up in the coastal waters of Ano Nuevo State Reserve, which reportedly spiked in the presence of elephant seals to worrying levels. The amounts have risen by 17% during molting season, when their skin and hair is shed into the nearby waters, and nearly doubled during mating season.
It had drawn the attention of researchers, and moved further to investigate the problem. They found that 99% of the seals amass incredibly high concentrations of mercury within their body, amounts that would cause neurotoxicity to humans. The element is further spread through their environment, their surroundings as well as their predators.
Through shed skin and hair, elephant seals cause the levels of mercury in the waters to skyrocket. According to researcher Jennifer Cossaboon, where “seals or sea lions are eating and defecating and molting”, the levels spike and it’s a matter that should be further looked into, as it remains unknown what damage it may cause to the environment.
A previous study by Russell Flegal, in 1981, has remarked upon the high content of mercury laced into the coastal waters and beaches due to the feces of elephant seals. While it has been the root of newer researches, the theory was somewhat disbanded with the rise of new technology.
According to the study’s author, microbiologist Flegal, they were able to look at “seasonal changes” this time around, and understand that the molting was primarily to be blamed on the toxic levels of methyl mercury in the water, due to the fact that the mammals often don’t eat while on land. If they abstain from intake of food, there would be less to excrete.
However, it may be transferred to their natural predators, who up their mercury levels by simply eating the elephant seals, because, according to Cossaboon, “mercury is an element, so it never breaks down”, it only changes its form in its new host.
A colony of 4,000 seals can reportedly bring as much as 120,000 pounds of mercury laced shed skin into the adjoining waters of their breeding grounds. The high toxicity may be quite harmful to humans, but it’s still unknown in its effects on the mammals.
According to co-author of the study, Sarah Peterson, who specializes in ecology and evolutionary biology, it’s important to take caution, and not jump to the assumptions that such toxic levels could be potentially lethal for surrounding species.
Even more, researchers are unclear on what high concentration of mercury means for elephant seals, other than the fact that they’re spreading it throughout their nearby waters.
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