Endangered Freshwater Mussels Harmed by Climate Change

Climate change has introduced some permanent changes to the ecological and biological system of our planet. Off lately, freshwater mussels in North America have become victims of rising water temperatures, according to a latest study.

Due to the global climate change, there has been a significant change in the water cycles. According to the latest study by scientists at the U.S. Geological Survey, the rise in the water temperature due to the climate change is a great threat to the already endangered or threatened native freshwater mussels in North America.

Scientists conducted laboratory tests and discovered that a few species of the freshwater mussels have suffered a decline in heart and growth rates due to the significant rise in water temperatures. These mussels are compared to the 'canary in the coal mine,' meaning that they prove to be good indicators of good water and sediment quality of the U.S. Rivers. Also, the freshwater mussels are an important community of the food web, as they connect and control several trophic levels.

"Native freshwater mussels may be especially sensitive to climate change because of their patchy distribution, limited mobility, and dependence on host fish for their larval stage, as well as fragmentation of their ranges by habitat alteration," Teresa Newton, USGS scientist and an author of the report, said in a statement. "Many species are currently in danger of extinction."

For the study, scientists analyzed the effect of high water temperature- 68-95 degrees Fahrenheit (about 20-35 degree Celsius) on three different species of freshwater mussels that were two months old. The three species were pink mucket, fat mucket and washboard. When the temperature ranged from 25.3-30.3 degree Celsius nearly 50 percent of the mussel's population died. Researchers also witnessed a significant decline in the heart rate of pink mucket and washboard mussels as the temperatures of the water increased, according to a news release.  

According to the study researchers, warmer waters of the future could lower the biodiversity and trigger a shift to more temperature-tolerant mussel species.

"Freshwater mussels are the most endangered group of organisms in the U.S. and in the world," Newton said. "More estimates of the upper thermal limits in native mussels are urgently needed to assess the potential effects of global climate change on native mussel populations."

According to the study reports, nearly 70 percent of the 302 mussel species in North America are extinct or imperilled. Pollution, water quality degradation and habitat destruction have led to the decline in the diversity of mussels.

The findings have been documented in the journal Feshwater Science.