“Marine mammals are very good sentinels for ocean and human health, and they really act like the proverbial canaries in a coal mine,” said Dr. Greg Bossart, a veterinary pathologist and senior vice president in charge of animal health at the Georgia Aquarium. “They give us an idea of what’s occurring in the environment.”
So far this year, nearly 1,000 bottlenose dolphins — eight times the historical average — have washed up dead along the Eastern Seaboard...
The high death toll ... has alarmed marine scientists, who say it remains unclear why the dolphins have succumbed to the disease. The deaths, along with a spate of other unrelated dolphin die-offs along Florida’s east and west coasts, raise new questions about the health of the ocean in this part of the country and what role environmental factors may be playing, scientists said.
... each group of dolphins faces separate challenges that in some cases remain scientifically murky — disease, a polluted environment, infection and possible residue from the BP Deepwater Horizon oil spill in 2010. “It is alarming when you see so many different die-offs of marine mammals going on at once,”... [emphasis mine]