Toxins: Equally dangerous to dolphins is contaminated warm water, caused by the global warming effect of companies dumping chemical additives to the ocean. 

It was reported in the US in March 2015 that 60% of the dolphin population on the East Coast had been killed by chemical contamination and global warming. These big companies are creating a giant, boiling cauldron of death for marine life, and the dolphins, the most fragile of marine animals, are suffering the consequences. But, sadly, the opposite can also be true.

In Mississippi and Alabama in 2011, marine scientists from Dauphin Island Sea Labs reported a correlation between large pulses of chilly water (the likely source being the melting ice caps of the Arctic ocean) entering Mobile Bay and dozens of stillborn dolphin calves washing up on the beaches. 

Oil spill: Some environmentalists, however, argued that the Mississippi and Alabama issues could be yet another after effect of the Deepwater BP oil spill in 2010 – either the toxic effect of the oil itself or the toxic effect of the cleanup operation.

Dead dolphins examined by autopsy between 2010 and 2012 after the oil spill in the Gulf of Mexico showed levels of bacterial pneumonia, adrenal disorders and severe lung lesions that were far more serious than a control group of bottlenosed dolphins not in the oil spill area. “These dolphins had some of the most severe lung lesions I have seen in the over 13 years that I have been examining dead dolphin tissues from throughout the United States,” said Kathleen Colegrove, the study’s lead veterinary pathologist, based at the University of Illinois, in a statement reported by Newsweek magazine on 20 May 2015.