Study finds malnourishment contributed to Mobile Bay whale death

Mammal was only sperm whale ever seen in Mobile Bay

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DAUPHIN ISLAND – A sperm whale that died after wandering into Mobile Bay in November, was malnourished, a post-mortem examination found.

The whale may not have eaten for weeks or months before it stranded in the bay, far from the deep water the species usually inhabits, according to a necropsy, or animal autopsy.

After the whale was discovered in Mobile Bay on Nov. 19, members of the Alabama Marine Mammal Stranding Network, followed the animal studying its movements as it swam as far north as Montrose, according to reports in 2020.

On Nov. 25, after the whale had stranded itself several times, scientists decided that the animal would have to be euthanized.

“The sperm whale was a young adult male that was more than 33-ft long and weighed over 32,000 pounds,” ALMMSN veterinarian, Dr. Jennifer Bloodgood said in a statement.

The network provided photographs of the whale’s tail to the National Oceanic and Atmospheric Administration’s Southeast Fisheries Science Center, which collects and maintains photographs to identify individual whales, much like using a human fingerprint.

“We learned that this whale was previously photographed in the Gulf of Mexico in 2012, nearly 200 miles off the coast of southwestern Florida. Based on this and other natural history information, we estimate this whale was between 12 and 20 years old,” said Bloodgood.

After the whale was killed, external and internal examinations confirmed the whale was in very thin body condition and its stomach chambers were empty except for indigestible, hard parts including squid beaks and shell fragments from crustaceans, according to reports.

“While malnourishment itself could have led to the whale’s stranding, the reason behind the malnourishment remains unknown,” Bloodgood said. “We were able to examine or test for several other common causes of stranding, such as some infectious diseases, marine debris, and trauma, but those were ruled out.”

During the necropsy, ALMMSN collected more than 450 samples to better understand this stranding and learn more about Gulf of Mexico sperm whales. Some tests, including for contaminants, such as heavy metals and biotoxins, are pending results.

Sperm whales are protected under the Endangered Species Act and the Marine Mammal Protection Act. Fewer than 800 individuals are believed to be in the Gulf of Mexico. On average, only two sperm whales strand per year in the Gulf. The mammal that died in November was the first live sperm whale to ever strand in Alabama.

Anyone who finds a stranded marine mammal in Alabama is asked to call the ALMMSN at 1-877-WHALE-HELP (942-5343) as soon as possible.