The massive, sucker-covered carcass of a giant squid washed onto the rocky shore of Scarborough Beach in Cape Town, South Africa, Tuesday (Aug. 16). The beast, which measured nearly 14 feet (4.3 meters) long, was the second giant squid to crop up on a beach in the region this year, according to the South African news site news24 (opens in new tab).
The last known giant squid (Architeuthis dux) to wash ashore near Cape Town showed up about 6 miles (10 kilometers) northwest of Scarborough Beach, on Long Beach in Kommetjie, on April 30, Live Science previously reported. That cephalopod measured roughly 11.5 feet (3.5 m) long. For comparison, the largest giant squid ever seen measured a whopping 43 feet (13 m) long, and some studies suggest that the creatures could potentially reach 66 feet (20 m) long, although no squid of such size has ever been spotted.
The squid that washed onto Scarborough Beach this week seemed to be another A. dux specimen, said Mike Vecchione, a National Oceanic and Atmospheric Administration invertebrate zoologist stationed at the Smithsonian's National Museum of Natural History in Washington, D.C. "Although other large squids exist, I am fairly certain this is a true giant squid," he told Live Science in an email.
Other squid species, including the colossal squid (Mesonychoteuthis hamiltoni), rival A. dux in terms of sheer size, and some scientists argue that the Architeuthis genus actually includes a variety of giant squid species, rather than A. dux alone, according to the Smithsonian (opens in new tab).
Related: Why are there so many giants in the deep sea?
Giant squid species beak reveal (by attending marine biologist) - Scarborough wreck this morning. pic.twitter.com/9Mr9QbjZmiAugust 16, 2022
Without an examination of its internal organs, it's difficult to guess how the Scarborough Beach squid perished, Vecchione said. "Note that most of the skin has abraded and some of the arms are broken off, but this (especially the skin abrasion) can result from washing up on the rocky shore." The remaining skin on the squid's mantle — the muscular sheath that houses its organs — gleamed ghostly white in the sun.
It may be that the squid ventured into shallow, near-shore waters to feed and got struck by a ship propeller, "but this is difficult to prove without witnesses," Dylan Clarke, a marine scientist and curator at Iziko South African Museum, told news24. "The literature … suggests that they come up into shallower waters because they display a behaviour called diel vertical migration. In other words, they venture into shallower waters during the evening to feed and migrate back to deeper waters during the day."
Giant squid generally live in frigid waters some 1,640 to 3,280 feet (500 to 1,000 m) beneath the ocean surface, and they use their dinner plate-size eyes to peer through the inky darkness, according to the Smithsonian. Based on where the animals have washed ashore, scientists think the squids may inhabitat all the world's oceans, but they're most frequently seen on the shores of New Zealand and Pacific islands, on the east and west sides of the North Atlantic, and in the South Atlantic along the African coast.
"Strandings of Architeuthis on South African shores are not unusual at all," Vecchione told Live Science. "It is one of several places around the world where they show up regularly."
Officials gathered tissue samples from the squid carcass on Scarborough Beach, and these will soon be examined by researchers at the Iziko South African Museum, Gregg Oelofse, the City of Cape Town coastal manager, told news24. Scientists could use such samples to sequence the animal's DNA and run chemical analyses to detect pollutants and stable isotopes — nonradioactive chemical elements with varying numbers of neutrons in their nuclei — in its flesh, Vecchione said. The isotope analysis would provide hints about the squid's feeding history, as would an examination of the animal's digestive system.
In addition, scientists could determine how old the squid was based on its reproductive organs and statoliths, small mineralized masses that sit inside sensory organs in the squid's head and accumulate "growth rings" over time, Vecchione said. Past studies of these statoliths suggest that giant squid can live to be about 5 years old, according to the Smithsonian.
"The availability of information on giant squids is relatively poor and is either based on dead or dying animals that have been washed ashore or captured in commercial trawl nets," Clarke told news24. The newfound Scarborough Beach squid will join a collection of giant squid specimens at the Iziko South African Museum that were largely acquired through such strandings or incidental catches during bottom trawls, he said.
Originally published on Live Science.