As humanity tries to battle with the more obvious consequences of climate change, some that might slip by unnoticed are brimming out of our sight, under the blue warming waters.
The increasing frequency and severity of storms as a result of climate change has turned out to be the key factor in a mysterious skin condition in coastal dolphin populations that was first noticed by scientists nack in 2005.
The study was published in the journal Scientific Reports.
Decreased water salinity brought upon by climate change
Researchers first started noticing the skin disease on approximately 40 bottlenose dolphins near New Orleans after Hurricane Katrina hit back in 2005. The disease was seen to cover as much as 70% of the dolphin's bodies and could prove fatal.
The disease has been killing dolphins ever since with significant outbreaks in Louisiana, Mississippi, Alabama, Florida, Texas, and Australia.
The dolphins had patchy skin and lesions that caused discoloration covering up most of their body with fungal and bacterial species. It was found that a sudden and drastic decrease in salinity in the waters due to climate change was the common factor in all of the cases.
The growing severity and frequency of storm events dump unusual amounts of rain that turns coastal waters to freshwater. Especially after intense storms, this condition can last for months, and since coastal dolphins do not live in freshwater, they develop skin lesions due to the decreased water salinity brought upon by climate change.
"This devastating skin disease has been killing dolphins since Hurricane Katrina, and we're pleased to finally define the problem," Marine Mammal Center's chief and study co-author Dr. Pádraig Duignan said. "With a record hurricane season in the Gulf of Mexico this year and more intense storm systems worldwide due to climate change, we can absolutely expect to see more of these devastating outbreaks killing dolphins."
Researchers are expecting the condition to be more common as time passes and long-term consequences of climate change are more felt, and the long-term outlook for dolphins affected by the disease is poor, especially in cases where there is prolonged exposure to freshwater. Researchers are hoping that the study can better help professionals diagnose and treat dolphins in the future.
"As warming ocean temperatures impact marine mammals globally, the findings in this paper will allow better mitigation of the factors that lead to disease outbreaks for coastal dolphin communities that are already under threat from habitat loss and degradation," Duignan said.
"This study helps shed light on an ever-growing concern, and we hope it is the first step in mitigating the deadly disease and marshaling the ocean community to further fight climate change."