Due to the decrease in the salinity of the water, dolphins develop severe and painful dermatitis which causes their death.
several Dolphins are dying along the coasts of the United States, South America and Australia from one lethal dermatitis. Dolphins affected by the disease die slowly and painfully as a result of severe skin lesions, similar to burns, which appear after exposure to fresh water.
The disease was first documented in 2005 in a group of dolphins trapped in a lake in Louisiana following Hurricane Katrina. Since then the cases have gradually increased and a recent study has linked them directly to the climate crisis.
Researchers who analyzed the deceased dolphins have indeed established that the onset of the disease is linked to extreme weather events, in particular to storms and heavy rains that modify the marine habitat, decreasing its salinity.
Tursiops australis can survive in freshwater for short periods: if the salinity of their habitat decreases or if the animals are trapped in unsalted waters for a long time, they develop a dermatitis which can affect up to 70% of the skin, therefore as serious as a third degree burn incredibly painful.
Animals often die from pain, while in other cases dermatitis causes fatal bacterial, fungal or algal infections.
The most exposed dolphins are those that live in coastal habitats or near river mouths, some belonging to species already risk of extinction.
Probably the sensitivity of dolphins to the salinity of the water is limited and they do not realize in good time that they are in an inappropriate environment.
"It's like humans: we know we need to breathe oxygen, but if you were locked up in a house that was slowly filling up with harmful gases, it would only be once a crisis point was reached that you would probably be aware of it," he explained. Nahiid S. Stephens, one of the researchers who analyzed the deceased dolphins.
The link between the disease and the climate crisis seems clear and cases are likely to increase. Unfortunately, the researchers do not know how to reverse the trend, but they hope that the results of their study contribute to the awareness of all of us about terrible consequences climate change.
Reference source: Nature
Read also:
- What are the plastic objects that kill the most dolphins, whales and other marine animals
- Hundreds of scientists sound the alarm about real and imminent risk of extinction for whales, porpoises and dolphins
- Taiji Bay: the hunt (and slaughter) of dolphins starts again. Already captured 4 specimens
