Necropsy Reveals Maris The Beluga Whale’s Cause Of Death

Photo by Caroline Ashburn

By Daniel Stanton

It has almost been two months since the death of Maris, the twenty-one –year-old beluga whale.

Maris suddenly and unexpectedly passed away October 22nd, 2015 around 2pm at the Georgia Aquarium after living in their care for ten years. She was born in 1994 at the New York Aquarium and was moved to the Georgia Aquarium in 2005.

The staff at the Georgia Aquarium is still coming to terms with the sudden loss of Maris. The bonds that were formed between trainers and the beluga were special and Maris was one of the first beluga whales at the Georgia Aquarium. Our hearts go out to the teams at the Georgia Aquarium.

Veterinary teams routinely examined Maris. Upon Maris’ last exam the morning before she suddenly died, the team found that she was a healthy beluga whale. They conducted an ultrasound as a routine part of the exam and found no abnormalities. She ate normally and engaged with the animal care team, trainers, and the other whales.

With no warning, Maris suddenly passed away, the cause of death was unknown.

The other two belugas (Grayson and Qinu) appeared anxious the day of her death, but have since recovered and resumed normal activities.

Georgia Aquarium veterinarians and University of Georgia pathologists conducted a necropsy to determine the cause of death. The results of the necropsy were released yesterday and concluded that Maris died of an acute heart failure. Her heart and other tissues examined had microscopic lesions. The necropsy report stated that the condition she had was hard to detect. This was a case of an acute animal death.

The official cause of death was “acute heart failure from unknown etiology”. There was no report or evidence that Maris had a predisposition to heart failure. Additionally, there was no evidence of any infectious disease.

This is not the first report of a beluga dying from heart failure in human care.

Tiqa died at the Vancouver Aquarium in September 2011, although the cause of heart failure was different.  Unlike Maris, Tiqa’s heart failure was due to an infection. The infection caused a buildup of fluid around the heart. The cause of death was pleural and pericardial effusion and interstitial pulmonary edema due to cardiovascular collapse.

This is different than Maris’s case, but there are also some similarities. Both whales died suddenly and there was nothing that anyone could do predict or prevent these deaths. Lesions were also found in the heart and other organs indicating that Tiqa had ongoing heart failure. The Vancouver necropsy team even suggested that the cause of the heart lesions was unknown but could be congenital, related to toxins, or possibly due to an, as yet, undetected virus or other organism.

Given the history of acute heart failure in both whales, it stands to reason that there  may be a single underlying cause that contributed to their deaths. While Tiqa had an infection, Maris did not, as reported both by her previous exam the morning before her death and the necropsy. This leaves a common culprit between the two cases. The heart lesions could be congenital.  This should be explored more, but the problem is that we still are learning about beluga whales and if it weren’t for beluga whales in captivity, we may not even know that there could be genetic propensities that make them more likely to have heart lesions. This is just an observation at this point gained from the comparison of the two deaths. More work needs to be done to fully understand if genetics played a role in the development of lesions and if there can be a link between this and the deaths of both belugas.

Regardless, the hearts of the Awesome Ocean family go out to the Georgia Aquarium during this difficult time, and we stand with you to support your efforts. We hope to learn more about belugas and their genetic predispositions through research. It is aquariums and the combined efforts of dedicated researchers, animal care teams, training teams, and veterinary teams that help us to learn more about these amazing and graceful animals. We stand with you.

Daniel Stanton has a passion for animals and conservation. He holds a Master’s of Science Degree in Biology from Winthrop University where he did his thesis on the evolution of circadian clock genes in the lower Metazoa. He is a Sr. Biological Scientist at the University of Florida, and has experience in various areas of biology. Mr. Stanton has presented his research at many scientific meetings and worked on many scientific publications in collaboration with fellow researchers. He believes that one person can make a difference and create a wave of positive change.