It might have been a bit startling to see, if not smell: a small pickup truck, headed north on I-95 in late August, its bed full of irregularly bulging black contractors’ bags, an essence of decay wafting from behind it like so much putrid exhaust. To the driver and his assistant, however, it was a prize haul.
Inside those bags were the mostly skeletonized remains of a female orca, scientifically known as Orcinus orca, the largest member of the dolphin family.
A few days later, John Ososky and Teresa Hsu—both collections specialists at the Smithsonian’s National Museum of Natural History—heave the bags out of the pickup and begin pulling the contents out, placing them on a low steel exam table and across the gray concrete floor of the Osteo Prep Lab at the Museum Support Center in Suitland, Maryland.
Ososky, Hsu and an assistant—wearing purple latex gloves and thick rubber boots—start hosing down the bones, blackened by a mix of dirt and surface oil; carving off any bits of flesh still hanging on; and assembling them. It quickly becomes evident that this had been a fairly large animal. It is also the first time Ososky and Hsu have a chance to closely examine their catch.
“It looks like one of the vertebrae just sort of blew out,” says Ososky, examining a section of the spine near where it joined the animal’s tail.
The one vertebra is abnormally devoid of bony content, hollowed out like a shallow bowl. Hsu says it appears to be an old injury and could be indicative of trauma, cancer, an infection or maybe even a blow from a ship.
They also see what looks to be a healed-over crack on a scapula (shoulder blade), which could be due to arthritis or also potentially a boat strike. “Those are things we want to look at to try to learn more life history information from the skeleton,” says Ososky.
While there are no plans for it to appear as an articulated skeleton in the Natural History Museum’s Sant Ocean Hall, the orca—along with a genetic sample—will go in the museum’s collection of some 18,000 marine mammals. The skull will be stored on a shelf with other orca skulls, and the rest of the skeleton will go in a collection case, where it will be available to researchers. It will be the first full adult skeleton from the Atlantic Ocean in the collection. (Older, mature animals are of more use than juvenile specimens.) A majority of the killer whale specimens already in the collection come from the Pacific Ocean. Ososky says he expects the skeleton will be of great interest, in part because of the orca’s unique stranding location.
The female whale was found stranded in January on a beach near Palm Coast, Florida. After her death, the National Oceanic and Atmospheric Administration (NOAA) and the Florida Fish and Wildlife Conservation Commission coordinated a post-death study, called a necropsy, and analyses of the animal’s tissues. The orca was then taken to an undisclosed location at the University of Florida in Gainesville. Following Ososky’s instructions, workers heaped hay on top of the whale and put a wire cage over the carcass to keep vultures and other scavengers away. Over the succeeding months, the creature essentially composted, rotting down to the bones.
Now, at the Osteo Prep Lab, the skeleton will bathe in water—to degrease the bones—until late October or so, and then it will get a soak with a mild ammonia solution for at least a couple of weeks that will sanitize it and get rid of any lingering odors from the microbes that strip the final organic matter off the bones, says Ososky.
No one knows why the orca was in the Florida waters, he says: “It’s not a hot spot for orcas exactly.” Researchers have taken genetic samples and will aim to link up this female with other known populations in the Atlantic, but as yet it’s not clear where it came from.
Ososky became aware of the beached whale through a network of scientists and wildlife specialists who respond to strandings. He doesn’t always accept offers to collect specimens, but this one was different, he says. While Ososky has processed some 1,500 specimens of marine mammals, mostly cetaceans and seals, over the 25 years he’s been with the Smithsonian, he says, “this is the first orca stranding that I’ve responded to.”
The new specimen could help address scientists’ questions about the species. “One of the things you want to know is how are [orcas] changing through time,” says Ososky. This orca’s bones could provide some answers.
Orcas are found in higher density in colder waters, but they are known to be in the waters off the eastern United States and in the northern Gulf of Mexico, says Erin Fougeres, a marine biologist with NOAA who administers the agency’s marine mammal stranding response program for the southeast region, which encompasses North Carolina to Texas, Puerto Rico and the U.S. Virgin Islands. Only two previous orca strandings have been recorded in that region—one in 1948 and another in 1956, says Fougeres, who is not involved in the Smithsonian’s preparation of the skeleton.
“Killer whales are out there—we just don’t get them regularly stranding on our beaches,” says Fougeres, who adds that scientists estimate that 14,000 orcas live in the Atlantic.
The post-mortem studies of the museum’s specimen indicate that the female was about 21 feet long and showed signs of age, including a benign fibrous tumor in her reproductive tract, says Fougeres. Females in the wild can live up to age 90, but 50 years is a more typical life span, she says. Researchers will cut into the specimen’s teeth and, just as they do with trees, count the rings that are exposed by the cutting to get an estimate of her age.
It’s not clear why she became stranded. Tissue studies show some bleeding in her lungs and muscles, and some fluid buildup around her heart, but that all could have happened while she thrashed on the beach, says Fougeres.
Getting the bones is important, because they may tell more about how the animal lived and died, and provide a starting point for scientists doing comparative research.
“Having the skeleton is really valuable, because you can keep learning from the animal even after we’ve done the necropsy and we’ve examined the tissues,” says Fougeres. With the bones, “you can see what could potentially be additional age-related bone degradation or maybe trauma,” she says.
Researchers might, for instance, pursue what caused the orca’s vertebra to disintegrate. Ship strikes on whales and dolphins have become increasingly common on the East Coast, affecting minke, humpback and right whales, says Fougeres. “But I can’t say that’s what happened for this whale,” she says.
Having a physical skeleton or skull to study is critical, says Eric Archer, a marine mammal geneticist with NOAA’s Southwest Fisheries Science Center. Unlike this particular case, specimens housed in museums tend to be a species prototype, which helps in classifying potentially new species. “Also, there are measurements and features that we don’t know yet might be important,” he says. It’s good to be able to go to a specimen and “say, ‘Ah, we never looked at this particular feature,’” says Archer.
Sometimes a difference can’t be measured but can be differentiated by the human eye, he says, adding, “Collections are critical.”
“This really does give us an opportunity for a unique data point,” says Ososky. “I don’t know where this whale came from. I don’t know what’s happened to it in its lifetime. There’s a lot we can learn about it.”