Dolphins in the Gulf of Mexico are still struggling to give birth in the wake of the 2010 BP oil spill, a new study reports.
According to CBS News, the government study tracked the health of dolphins in Barataria Bay, an estuary near New Orleans that was hit hard by the disaster which emptied 130 million gallons of oil into the Gulf. Researchers estimated 35 percent of the 2,300 dolphins living in Barataria died as a result of the spill.
The researchers monitored 10 pregnant dolphins over the course of four years and found that only two of the dolphins gave birth to calves. Cynthia Smith, a researcher in the study, said the dolphins’ reproduction difficulties may be due to ongoing health problems from swimming through oil slicks in Barataria.
The study, published Tuesday in the Proceedings of the Royal Academy of Sciences in Britain, is one of many investigating the impact of the BP oil spill on dolphin populations. Another study in 2011, a year after the spill had been stopped, tagged 21 dolphins and followed them. Scientists found they were prone to a high mortality rate and diseases which harmed their ability to reproduce.
Even under ideal conditions, dolphins are slow to reach reproductive age, and have a gestation of about year. They only give birth every three to five years.
While BP is insistent the Gulf of Mexico has recovered, scientists warn the spill could have far-reaching effects on the region’s wildlife, and say that more research is needed to determine the full scale of the environmental damage.
“The take-home message is that this dolphin population, as well as other dolphin and whale populations that were exposed to the Deepwater Horizon oil, will take a long time to recover,” said Lori Schwacke, a wildlife epidemiologist with the National Oceanic and Atmospheric Administration and the recent study’s lead researcher.
As of last week, BP has declined to comment on the study.