Climate change causing deadly skin disease in dolphins

In recent years, an increasing number of dolphins evolving in coastal waters have developed severe skin disease. According to this new study, this condition is directly linked to climate change.

A close link

In the context of work recently published in the journal Scientific Reports, US researchers have shown that the increasing frequency and severity of storms due to climate change is a key factor in the development of a potentially fatal skin disease in dolphins, radically altering the salinity of the coastal waters in which the animals live.

Climate change is reshaping Earth’s weather systems, and intensifying storms is one of its main consequences. Work has previously shown that increasing heat in the upper ocean layer is contributing to the increase in the power of hurricanes, while reports from theWorld Meteorological Organization have shown that extreme weather events like cyclones and heavy rains are increasingly common around the world.

One of the byproducts of these phenomena is the dumping of huge amounts of fresh water into the seas and oceans, which causes a rapid and significant decrease in their salinity, which can last for months. For dolphins that live in coastal areas, this means the sudden onset of alien and unfavorable conditions, the main factors of which researchers were unaware of until recently as well as the health consequences of cetaceans.

In fact, it was not until two recent waves of mortality in Australia among distinct populations of coastal dolphins so researchers can draw parallels. Both groups of cetaceans exhibited discolored skin and lesions covering up to 70% of their body, while samples taken revealed the presence of fungal and bacterial populations. According to the team, the two outbreaks followed a ” abrupt and marked drop in salinity over several weeks or months ”, Due to heavy rainfall in neighboring watersheds.

“It was essential to be able to better understand the problem”

Combined with environmental factors, these observations allowed the authors of this new study to create the very first case definition for a so-called freshwater skin disease, and to establish what they consider to be a link between this condition and the climate change. The hope remains that research can help professionals to better diagnose and treat dolphins affected by this disease which will continue to progress in the years to come.

” This devastating skin disease has been killing dolphins since Hurricane Katrina, it was essential to be able to better understand the problem », Explains Dr Pádraig Duignan, chief pathologist at Marine Mammal Center and lead author of the study.

” With a record hurricane season in the Gulf of Mexico this year and more intense storm systems around the world due to climate change, we absolutely must expect to see more of these devastating epidemics.. “