Last month, Biologist Peter Ward was on an exploratory trip off the coast of Ndrova Island in Papua New Guinea, when he saw something he hadn’t seen since 1986: a specimen of Allonautilus scrobiculatus, otherwise known as the crusty nautilus.
Before the crusty nautilus made its reappearance in July, only two humans had ever reported seeing it: Ward and his colleague, Bruce Saunders. But ever since, the animal has eluded searchers and many marine biologists feared that it had gone extinct. Ward returned to where he and Saunders first found the mollusc to see if any had survived being hunted for their shells and ongoing environmental change.
“We not only found them, we captured the first digital images of them alive in the wild, and attached tracking devices that are revealing some of the oldest and deepest secrets of their survival,” Ward writes in a guest post for National Geographic.
The crusty nautilus differs in several ways from other nautilus species, with its shell being the most obvious. When compared with another species, like the more common Nautilus pompilius, the shell of the Allonautilus scrobiculatus has a fuzzy, slimy coating, which gives it its name. It also has several other features that distinguish it from other nautili, namely its jaws, gills and male reproductive system, James Urton writes for UW Today, a publication by the University of Washington, where Ward holds positions in both the Department of Biology and Department of Earth and Space Sciences.
To snap the rare photographs, Ward and his team set bait to lure the nocturnal scavengers into frame. Underwater cameras would run all night, capturing high-definition videos at depths of 500 to 1,300 feet below the surface as undersea animals swam by. One day, while reviewing the previous night’s footage, Ward got his first glimpse of the crusty nautilus in 31 years, Urton writes.
Because nautili have a narrow band of cold temperatures where they can live, Ward and his team brought several captured specimens to the surface in cold water, where they took samples before releasing them at the capture point, according to Sci-News.com. The molluscs, which are distantly related to squid and cuttlefish, are commonly called “living fossils” because their shells have been found dating back 500 million years in the fossil record. While they are one of the oldest species on the planet, they are threatened by “nautilus miners” who hunt and kill them to sell their shells as souvenirs, Urton writes.
“Once they’re gone from an area, they’re gone for good,” Ward tells Urton. “As it stands now, nautilus mining could cause nautiluses to go extinct.”
In September, the United States Fish and Wildlife Service will decide whether to advocate for nautili to be added to the protected species list under the Convention on International Trade in Endangered Species of Wildlife Fauna and Flora. If nautili become protected, international trade of their shells could be curbed and give the nautilus a chance to thrive.