Pygmy Sperm Whale on Florida Beach Was Emaciated with Abnormal Heart Tissue

Yet another gentle giant has been found dead on a beach, adding an additional tragedy to the list of whale strandings along the East Coast of the U.S. in recent months.

The 10-foot-long pygmy sperm whale was found early on Friday morning in Indialantic, Florida, on the seashore just in front of BLEU Beach Resort, Florida Today newspaper reported.

While the exact cause of the whale's death has not yet been determined, researchers who have examined its body found that the mammal was very thin, with damage to its heart tissue.

Wendy Noke Durden, a research scientist at the Hubbs-SeaWorld Research Institute in Florida, told Newsweek: "Although it will be a while before we receive the histopathology [tissue study] results, which may be able to provide a definitive answer, upon examination the most significant findings were emaciation and abnormalities in the heart tissue. These were consistent with cardiomyopathy or heart disease.

"Cardiomyopathy has been documented to be the most common cause of stranding for this species and likely contributed to the mortality of this animal."

Pygmy sperm whales are a rare species found across the world. According to The National Oceanic and Atmospheric Administration (NOAA) Fisheries, the whales can grow to lengths of up to 11.5 feet, and weigh between 700 and 1,000 pounds.

Until 1966, pygmy sperm whales were thought to be the same species as dwarf sperm whales, which are similar-looking and around the same size. Their namesake, the sperm whale, can grow up to 60 feet long in comparison.

The most-recent NOAA Fisheries data estimates that the population of pygmy sperm whales in the western North Atlantic is around 7,750. Populations off Hawaii and the West Coast and in the Gulf of Mexico are estimated at 42,000, 4,000 and 300, respectively.

Because of their small numbers, not much is known about the behavior of pygmy sperm whales. They are thought to swim either alone or in small groups of between six and seven whales, and spend very little time at the ocean surface.

Pygmy sperm whales are capable of diving at least 1,000 feet to hunt for food, mostly feeding on squid, octopus, crustaceans and fish. Like their larger cousins, the whales use echolocation to find their prey. They emit high-pitched squeaks of sound and use the amount of time it takes that squeak to bounce back to detect their surroundings in the dark depths of the ocean.

These whales use a strange and unique tactic when threatened that only their close dwarf sperm whale cousins also utilise: they release clouds of dark liquid like a squid. The pygmy sperm whales have a sac containing over three gallons of this red-brown liquid inside their intestines, according to NOAA Fisheries. The mammals can also release it as a sort of smoke-screen if threatened, proving a distraction to predators as they escape.

"Pygmy sperm whales (Kogia breviceps) are commonly found stranded," Noke Durden said. "They are the second most commonly stranded cetacean [whale and dolphin] species in the southeastern United States.

"In our stranding response area, around 40 percent of Florida's east coast, we receive approximately three Kogia strandings each year," Noke Durden added. "It is very common for these animals to strand alive on the beach. Upon examination, it appeared that this most-recent whale likely stranded alive earlier in the morning."

Pygmy sperm whales are protected under NOAA's Marine Mammal Protection Act. Common threats facing the population include entanglement in fishing gear, whale hunting, ocean noise, eating marine debris, and being struck by boats and other vessels.

Kate Wilson, a spokesperson for the International Whaling Commission, told Newsweek in January: "Strandings occur for either natural reasons like age or disease or human-related factors such as vessel collisions or ocean noise. Animals may strand alive on the beach or die at sea before being carried onto land by ocean currents. Some strandings occur due to a combination of factors, and it's often very difficult to identify the cause of a stranding."

Several other whales have been found dead on beaches along the East Coast over the past few weeks, with two sperm whales and seven humpback whales stranding between December 1, 2022, and January 20, 2023. Multiple sperm whales have also washed up on Oregon beaches since the start of the year, some within days of each other.

"Our team responds to approximately 70 dolphin and whale strandings along the east coast of Florida each year, and the majority of these events are carcasses that wash ashore [around 16 percent strand alive]," Noke Durden said.

The reasons for most of these other recent strandings remain unknown.

"When animals do strand alive, most often it is because the animal is very ill and may be in the process of dying," Noke Durden added. "The stressors associated with the stranding process often result in the mortality of an already compromised animal."

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