Why Do Whales Beach Themselves?

iStock/shayes17
iStock/shayes17

Humans have observed marine mammals stranding themselves on land since at least the first century CE, when the ancient Romans and Greeks recorded beaching incidents. Modern marine biologists are only able to determine the cause of a beaching about 50 percent of the time, according to the Woods Hole Oceanographic Institution, and the reasons they find are varied.

Often the cause is obvious injury or illness. Disease or wounds from predators can leave an animal too weak to keep itself afloat, and at some point it gives up and lets the tides wash it ashore.

Cases where a group of animals beach themselves together, and not all of them exhibit signs of trauma, are more puzzling. One explanation biologists offer is that whales and dolphins, which hunt and travel together in groups called pods, fall victim to their own social structure. If the group leader or dominant animal is sick or hurt and runs ashore, the rest of the group might follow. Other times, the pod may just get itself stuck by a low tide after hunting or traveling too close to shore.

In some instances, mass beachings have occurred shortly after active use of military sonar in an area. In 2000, for example, 17 animals from four species (Cuvier’s beaked whale, Blainville’s beaked whale, Minke whale, and the spotted dolphin) were found beached within a 36 hour period in the Bahamas the day of, and after, a U.S. Navy sonar exercise. A joint Navy and National Oceanic and Atmospheric Administration (NOAA) investigation soon concluded that the tactical mid-range frequency sonars used by the Navy ships “were the most plausible source of the acoustic or impulse trauma” that occured. The evidence suggests that sonar may have both physical and behavioral effects on marine mammals.

Some animals also beach themselves purposefully as a hunting tactic. Killers whales, or orcas, frequently chase pinnipeds, like seals and sea lions, into the surf zone and onto shore, where the prey has to make a clumsy transition from swimming to walking in shallow, turbulent water. As the prey struggles to escape, the orca launches itself, or rides a wave, onto the beach and grabs the prey in its jaws. After the meal is secured, the orca can either wriggle back into deeper water or let a large wave lift it off the ground and back out to sea.

Could Gigantic Coconut Crabs Have Played a Part in Amelia Earhart’s Mysterious Disappearance? At Least One Scientist Thinks So

Getty Images
Getty Images

Amelia Earhart's disappearance during her attempt to fly around the world has captivated historians and conspiracy theorists for more than 80 years. One organization is now suggesting that her fate may have been sealed by giant crabs.

The International Group for Historic Aircraft Recovery (TIGHAR) believes that Amelia Earhart and navigator Fred Noonan may have landed their plane on Nikumaroro Island when they couldn't find their target, Howland Island, and that Nikumaroro's endemic crustaceans may have played a part in the ensuing mystery.

According to National Geographic, there are several clues supporting TIGHAR's theory. The large reef that hugs Nikumaroro’s coast makes it conducive to emergency aircraft landings. In 1940—just three years after Earhart’s disappearance—British colonists found 13 human bones beneath a ren tree on the island and shipped them to Fiji, where they were lost. The colony's administrator, Gerald Gallagher, sent a telegram back to England positing that it was Earhart’s skeleton. Then, in 2001, researchers uncovered U.S.-made artifacts around the ren tree including a jackknife, a woman’s compact, a zipper, and glass jars. The plot thickened even further in 2017, when four forensic bone-sniffing dogs all indicated that a human had indeed died at the site, though excavators failed to dig up any more evidence.

If those 13 bones beneath the ren tree did belong to the unfortunate castaway, where are the rest of her remains? Tom King, TIGHAR’s former chief archaeologist, thinks that coconut crabs can answer that question.

Nikumaroro is home to thousands of the colossal creatures, which can grow to a terrifying 3 feet across and weigh 9 pounds. They’re sometimes called robber crabs because of their penchant for absconding with objects that smell like food, and they’ll eat practically anything—coconuts, fruit, birds, rodents, other crabs, their own discarded body parts, and carrion.

It’s not unreasonable, then, to think that coconut crabs may have feasted on Earhart’s corpse and then taken her bones home with them. In one experiment to test the theory, TIGHAR researchers deposited a pig carcass on the island and filmed the aftermath. With the help of small strawberry hermit crabs, coconut crabs stripped the pig down to the bone in two weeks. After a year, some of the bones had been dragged 60 feet from the carcass’s original location, and some were never recovered at all.

King believes Earhart’s missing 193 bones could be hidden in the burrows of various coconut crabs. As in the pig experiment, crabs may have scattered some of Earhart’s bones dozens of feet away, but maybe not all of them—after all, the forensic dogs smelled bones near the ren tree that haven’t yet been located. Right now, TIGHAR is working with the Canine Forensics Foundation to further explore the area.

While we wait for more answers, dive into these other theories about Earhart’s disappearance.

[h/t National Geographic]

The Cat Sanctuary That Sits Near the Ancient Roman Site Where Julius Caesar Was Murdered

ClaireLucia/iStock via Getty Images Plus
ClaireLucia/iStock via Getty Images Plus

Cats will sleep anywhere—even in ancient ruins. Located in Rome, Colonia Felina di Torre Argentina is a cat sanctuary on the site where conspirators stabbed Julius Caesar 22 times outside the Theatre of Pompey, on March 15 44 BCE. Centuries later, in 1929, Mussolini excavated the area to reveal four temples that are 20 feet below the street level. Today, it’s the oldest open-air spot in Rome.

Bystanders can view the temple complex known as Largo di Torre Argentina from the fenced-off street, but according to Conde Nast Traveler, after a $1.1 million restoration process, the sanctuary will open to tourists in the second half of 2021. For now, the only living things allowed in the sacred area (area sacra) are feral cats.

According to Colonia’s website, they are "the most famous cat sanctuary in Italy” and also the oldest in Rome. Many of the cats fall into the special needs category: Some are disabled, missing part of a paw, or are blind; the special needs and elderly cats live in a walled-off area. Volunteers—a.k.a. gattare, or cat ladies—take good care of them, and some cats are available for adoption.

Atlas Obscura reports that “since the mid-1990s, the population has grown from about 90 to a peak of 250” cats and notes that the sanctuary has a spay/neuter program. From the street, visitors can watch gatti like the three-legged Pioppo and Lladrò—known as “poisonous kitten” because of how angry he was when he got there—sunbathe and sleep under pillars.

It’s unclear if the cats are respecting Caesar or disrespecting the fallen leader. However, a gift shop is open to visitors, and people can donate money toward the cats and/or volunteer.

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