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The research was led by Kristen J. Zemaitis of the University of Georgia\u2019s Odum School of Ecology<\/a>. The study tracked 133 wild alligators from the Okefenokee Swamp, Jekyll Island, and the Yawkey Wildlife Center.<\/p>\n In alligators from the Okefenokee, the average mercury level in blood was 0.62 milligrams per kilogram, and overall levels were about eightfold higher than at the two coastal sites.\u00a0<\/p>\n The experts reported that size and diet signals sometimes added to site differences, which helps explain why individuals in the same place can carry different burdens.<\/p>\n \u201cAlthough a naturally occurring element, mercury (Hg) is a potent neurotoxin,\u201d wrote Zemaitis. That\u2019s a clear risk signal for a top predator that reflects what is moving through the food web.<\/p>\n Mercury builds up in food webs<\/p>\n In water and wet soils, bacteria convert mercury into methylmercury<\/a>, an organic form that readily builds up in the living tissue of animals. This type of mercury moves most efficiently into food webs. <\/p>\n In addition, organisms do not get rid of methylmercury easily, and it accumulates over time. This process is called bioaccumulation<\/a>, the gradual build-up of a chemical in a living body. <\/p>\n When predators<\/a> eat prey that already contain mercury, the concentration increases again, meaning that species feeding higher on a food chain carry a heavier contaminant load. This process is called biomagnification<\/a>.<\/p>\n The study also used stable isotope markers to trace diet. Nitrogen isotope values tended to rise along with mercury in some sites, which is consistent with a shift toward bigger or higher-level prey.<\/p>\n Why the Okefenokee matters<\/p>\n The Okefenokee<\/a> is not just a scenic wetland. It sits at the headwaters of the Suwannee and St. Marys rivers.<\/p>\n That geography means contaminants do not stay put. Water flowing out of the swamp can transport mercury downstream into connected rivers and coastal waters.<\/p>\n Okefenokee water is dark and acidic, a classic blackwater system that is rich in natural organic matter. These conditions can favor the microbial processes that produce methylmercury from inorganic mercury.<\/p>\n Alligators, mercury, and humans<\/p>\n For people who fish or hunt, the findings add context to state guidelines<\/a> that advise how often certain species from specific waters should be eaten. The guidance aims to reduce long-term exposure, especially for pregnant people and children.<\/p>\n Mercury is a neurotoxin<\/a>, a substance that can damage the brain and nerves and, at high exposures, can also affect kidneys and the digestive tract. <\/p>\n The EPA<\/a> notes particular concern for fetal and infant development, since even modest prenatal exposures can have lasting effects.<\/p>\n Wildlife face parallel risks. Fish, birds, and reptiles can show reduced growth, impaired reproduction, or changed behavior when mercury loads climb.<\/p>\n Older and larger alligators tended to carry more mercury than smaller ones at some sites. That fits with trophic level<\/a> \u2013 the position in a food chain \u2013 where eating larger prey with higher mercury levels pushes body burdens upward.<\/p>\n The research team also measured hatchlings and found concerning values in some clutches. <\/p>\n Scientists have documented<\/a> the transfer of mercury from mother alligators to eggs, which means exposure can begin before a hatchling ever feeds.<\/p>\n Diet shifts matter too. As young gators switch from insects and small fish to turtles, birds, and larger fish, the chance of higher intake rises along with prey size.<\/p>\n What scientists still need to learn<\/p>\n Mercury pollution is not uniform. Local chemistry, water flow, and food web structure can change how much methylmercury forms and where it accumulates.<\/p>\n Tracing sources remains key. Atmospheric deposition from far away, historical inputs, and local releases can all contribute, and those drivers rarely act alone.<\/p>\n Better mapping of hotspots would help managers target monitoring and public advice where it matters most. The Okefenokee results suggest a need for careful tracking in connected rivers where people regularly harvest fish.<\/p>\n Eat fish, but choose wisely and follow local advice. People who rely on self-caught fish can lower exposure by picking species and sizes known to have less mercury.<\/p>\n Hunters can contribute by reporting harvest locations and allowing samples when asked by biologists. Those small steps build the datasets needed to protect both people and wildlife.<\/p>\n The research also highlights the value of healthy wetlands. When water quality improves, mercury risks can fall, and those gains ripple through food webs.<\/p>\n The study is published in the journal Environmental Toxicology and Chemistry<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.\u00a0<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Scientists working across Georgia and South Carolina report that mercury in some swamp alligators is far higher than…\n","protected":false},"author":2,"featured_media":254949,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[47],"tags":[192,79],"class_list":{"0":"post-254948","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-environment","8":"tag-environment","9":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/254948","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=254948"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/254948\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/254949"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=254948"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=254948"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=254948"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}