The tropical regions of our major planet are home to a overplus of colourful and strange fowl metal money , but our vibrant friends may be in danger . A new written report has unveil some of the highest - ever concentrations of atomic number 80 ascertain in tropical birds . The source ? Gold mining .

Until now , short was known about atomic number 80 contamination in thetropics . An international team of researchers sought to change that , analyzing 2,316 blood and feather samples from 322 bird species be across Central America , South America , and the West Indies .

The squad discovered the highest - ever concentrations ofmercuryfound in tropic songbird species – one unripe kingfisher even had 30 times the dependable amount . gamy levels were also found in tropical carnivorous and aquatic bird metal money ; in the former , the investigator put this down to hydrargyrum accumulation along the food Ernst Boris Chain , and in the latter , the collection of mercury in riverbeds .

But where did all this mercury derive from ? It can pass off naturally , spat out by volcano and stone in geologically alive areas of the tropics . However , in this case , the potential source was small - musical scale , or artisanal atomic number 79 excavation – this type of minelaying is the magnanimous informant of Hg pollution in the world .

“ The most important finding of our survey was that Hg assiduity were about four fourth dimension higher at sites impacted by artisanal and small-scale - scale gold excavation activities , ” said Chris Sayers , leading source of the discipline , in astatement .

Mercury is used in atomic number 79 mining as a quick way to access intemperate - to - reach , tiny atom of gold , as it can bind to the desire alloy . When these lumps of dental amalgam are heated , the mercury is vaporized , leaving only the Au . The mercury vaporisation either hold up into the basis , seeps into water , or go away into theatmosphere .

In their theme , the researcher describe mercury as “ a persistent pollutant that adversely impacts environmental , animal , and public wellness on a global scale . ” In tropical birds , gamy hydrargyrum point can affect their immune organization , making them more susceptible to disease . As tropical snort are often an index number of overall ecosystem health , the findings in the bailiwick suggest that mercury layer could be high in other species too , including humans – who also experiencetoxic effects – living near gold excavation operation .

As such , it ’s worth view if it ’s really necessary to use mercury in gold mining in the first position . agree to the researchers , the miners argue that it is , as it makes the process faster and more effective . Artisanalgoldmining can also be an important part of the thriftiness in small tropical community .

However , conscientious objector - generator of the sketch Claudia Vega enjoin that these communities should be informed about the environmental damage do by gold mining , although more research is postulate . This study involved local investigator , an approach that could help to guide these key conversations .

" This research serves as a wakeup call for bird preservation in the neotropics while also demonstrating the efficaciousness of heedful and just collaboration with local stakeholders , ” Sayers conclude .

The bailiwick is published inEcotoxicology .