In the past few years, scientists have seen coastal dolphins suffering from a mysterious skin condition that was soon found to cover almost 70 percent of their bodies and could become fatal. But recently scientists published a study that revealed the previously unknown reason behind this deadly skin condition.
The scientists who conducted the research found that the increasing frequency and severity of storms as an effect of dramatic climate change to be the key factor in this novel disease, by drastically altering the salinity of the ocean waters.
Even though many people still call climate change a hoax, the fact is that this dramatic change of the environment is reshaping Earth's weather systems and strengthening storms. Earlier, researchers found how increasing temperature in the upper layer of the ocean was encouraging more powerful hurricanes. The World Meteorological Organization also explained how extreme weather conditions like cyclones and heavy rainfall were gaining in frequency across the world.
The drastic changes in the climate are causing the release of a massive amount of freshwater into the ocean and it is causing a rapid and significant decrease in salinity that lingers for months at a time. For the inhabitants of coastal regions, dolphins, such changes mean a sudden shift to an unfavorable condition.
How Climate Change Is Killing Marine Creatures?
According to the recent study, published in Nature, in Australia, two remarkably similar mortality events involving dolphins enabled the creation of a case definition based on pathology and environmental factors. As per the researchers, both groups of the marine animals exhibited patchy skin and lesions covering almost 70 percent of their body, bearing fungal and bacterial species and discoloration.
The study noted that the common feature of both events was "an abrupt and marked decrease in salinity due to rainfall in the catchments, with hypo-salinity persisting weeks to months".
The study was conducted by Pádraig J. Duignan from The Marine Mammal Center in the US, Nahiid S. Stephens from the School of Veterinary Medicine in Murdoch University, and Kate Robb from Australia's Marine Mammal Foundation. The combination of pathology and environmental factors helped the scientists create the first-ever case definition for this "freshwater skin disease." It also enabled the authors to establish the link between skin condition and climate change. Now, they hope that this finding will help the professionals diagnose and treat the dolphins suffering from such conditions.
Dr. Duignan, the chief pathologist at The Marine Mammal Center said that this "devastating" skin disease has been killing the dolphins since Hurricane Katrina. With a record hurricane season in the Gulf of Mexico in 2020 and more intense storm systems worldwide due to the drastic climate change, "we can absolutely expect to see more of these devastating outbreaks killing dolphins".