They are as breathtakingly beautiful as they are toxically lethal. Tourists flock to the Matsu Islands from all over China to get a view of the “blue tears,” described as “an enchanting display of blue lights in the waters.” Experts say not to get anywhere near them because they will literally kill you.
Magical blue tears that kill everything around them
There’s no denying that the display of lights is breathtakingly beautiful. The magic behind the blue tears is that they “are caused by the bloom of tiny, bioluminescent organisms called Noctiluca scintillans, a type of dinoflagellate phytoplankton.” The big problem is they “can release chemicals in the seawater and harm marine animals.”
A study published in Geophysical Research Letters notes that the researchers tracked satellite data and it shows something really disturbing. The deadly toxic tears are “steadily growing.” They may look stunning but out of control growth is not a good thing. Similar to the more common but less attractive “red tide,” these colonies typically “produce toxins that poison fish, shellfish, marine mammals, birds and humans.” They won’t necessarily kill humans right away but the researchers warn playing in the contaminated water is risky.
After looking at “almost 1,000 satellite images from 2000 to 2017,” the scientists discovered a “signature unique to blue tears.” The wavelengths of light that they reflect is as distinctive as a fingerprint. The researchers were able to use that fingerprint to determine that “the bloom of dinoflagellates is expanding farther off-shore and into deeper waters in recent years.” Kind of like “the Blob” it seems to be endangering Godzilla.
Forming further out to sea
Generally, the blooms of blue tears form close to the shoreline but the satellite photos show “that many of them are also located farther out into the sea.” For the past 18 years, they have been a regular occurrence, usually starting to form in China’s summer months between April and August.
Marine biologists are alarmed because the organisms pose “a major threat to marine animal health. “Blue tears can poison life forms in the sea.” The Dinoflagellates themselves are not toxic, but they prefer to eat toxic algae. They excrete “ammonia and other chemicals that poison the water around them.” They also “take up oxygen until there’s none left in the surrounding waters.”
“The oxygen in the water is so low that many animals can die,” explains Chanmin Hu, an oceanographer with the University of South Florida. They aren’t really sure what caused the blue tears in the first place but the study noted a major factor “is the fertilizer runoff that comes from the Yangtze River.”