A dolphin swims through oiled waters in Barataria Bay, LA. Photo Credit: Louisiana Department of Wildlife and Fisheries (LDWF)

Marine Mammals Still Struggling on 10th Anniversary of Deepwater Horizon Disaster

FOR IMMEDIATE RELEASE

Contact:  steve.walker@nmmf.org

A Decade after the Deepwater Horizon Oil Spill, Dolphins, Whales Still Struggle to Survive and Reproduce

A Wake-Up Call about Caring for our Planet and Animals on the 10th Anniversary of the Deepwater Horizon Oil Spill

SAN DIEGO —April 20 marks the 10-year anniversary of the catastrophic Deepwater Horizon oil spill. A decade of scientific research indicates that the health of dolphins and other marine mammals in the Gulf of Mexico is not improving, and in some cases may be worsening.

“Our findings are disheartening and a stark reminder of the inextricable link between human activities and nature,” said Dr. Cynthia Smith, Executive Director and Chief Medical Officer of the San Diego-based National Marine Mammal Foundation (NMMF).

Dr. Cynthia Smith, Veronica Cendejas, and the field team perform a reproductive ultrasound exam on a dolphin in Barataria Bay, LA.
Dr. Cynthia Smith, Veronica Cendejas, and the field team perform a reproductive ultrasound exam on a dolphin in Barataria Bay, LA.
“Dolphins in the area of the spill have a low reproductive success rate of about 20% compared to 65% in dolphin populations that were not impacted by the spill. We don’t expect to see an improvement in reproductive success until the overall health of these female dolphins recovers,” Smith emphasized. The oil rig explosion caused a devastating flow of more than 130 million gallons of oil into the Gulf over an 87-day period.
NMMF research also indicates that dolphins in the Gulf continue to battle chronic, and potentially progressive, lung disease. These findings are consistent with human health studies, which have reported an increase in respiratory symptoms among individuals who responded to the oil spill, with some symptoms getting worse over time.
A dolphin swims through oiled waters in Barataria Bay, LA. Photo Credit: Louisiana Department of Wildlife and Fisheries (LDWF)
A dolphin swims through oiled waters in Barataria Bay, LA. Photo Credit: Louisiana Department of Wildlife and Fisheries (LDWF)

While scientists say the species of dolphins they are studying are not in danger of extinction, they have grave concerns about their long-term health and the health of the Gulf’s entire ecosystem. The oil-related health effects on offshore dolphins and whales, which include the critically endangered Gulf of Mexico Bryde’s whale, are expected to be similar to the Barataria Bay, Louisiana, dolphins that were closely studied.

Like people, dolphins and whales mature slowly and are long-lived. Many cetacean species do not produce their first calf until nearly 10 years of age and only a single offspring every three to five years. With so many sick and dead marine mammals in the wake of the Deepwater Horizon oil spill, scientific models predict it will take decades for their populations across the Gulf to recover.

A group of dolphins photographed by NMMF researchers as part of follow-up surveys to study reproductive and survival outcomes. The unique shape and pattern of notches in the dorsal fins allow for the identification of specific individuals.
A group of dolphins photographed by NMMF researchers as part of follow-up surveys to study reproductive and survival outcomes. The unique shape and pattern of notches in the dorsal fins allow for the identification of specific individuals.

The NMMF is committed to driving impactful science that will promote conservation actions with meaningful outcomes to protect these animals. With funding from the Gulf of Mexico Research Initiative, the NMMF is leading a consortium of researchers from across 10 organizations, including experts in veterinary medicine, pathology, immunology, cardiology, ecology, and statistical modeling. The research consortium has continued to study dolphins and other marine mammal species in the Gulf of Mexico to determine how and if they can recover following such a catastrophic environmental event.

NMMF’s Chief Scientist for Conservation Medicine, Dr. Lori Schwacke, helped lead the original Deepwater Horizon Natural Resource Damage Assessment for marine mammals. “The anniversary of the oil spill and ten years of research findings underscore the importance of continued studies of Gulf of Mexico marine mammals to provide the necessary science that best supports effective conservation. The challenges associated with studying these populations to describe both their recovery from past stressors and their responses to future threats require creative, big ideas.”

###

Did you enjoy this story? Sign up to receive the Latest NMMF news.
SHARE THIS JOURNAL ENTRY