At first, the black blob spotted between rocks along the shores of San Diego this week was mistaken for a ball of tar. But as a concerned surfer approached, it became clear that this was something special.
The finned creature had a gaping underbite that revealed nightmarish spiny teeth, small black eyes, a tentacle-covered appendage and bulb protruding from its head.
Scientists at University of California San Diego’s Scripps Institution of Oceanography swiftly identified it as a Pacific football fish, a deep-sea dweller so rare that only 31 specimens have been found in more than a century since it was first discovered.
The recent find, however, marked an even more remarkable moment. The Pacific footballfish is the third to wash ashore in California this year, a highly unusual event given its extreme reclusiveness.
At this point, no one knows how or why the fish appeared – but scientists are excited about the opportunity to learn more.
“The fact that a few washed up this year might just be serendipity for us,” said Ben Frable, an ichthyologist and the Collection Manager of Fishes at Scripps Institution of Oceanography who is examining and preserving the fish. He dismissed the idea that this was an indication that something was amiss. If that was the case, he said, there would be many more. But the two that were recovered this year (a third was photographed on the beach but disappeared before scientists got to the scene) are already offering the chance of new insights about the species.
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“We don’t know a lot about even the basics of how they live,” Frable said.
Made famous as the monster from the depths in Pixar’s Finding Nemo, the Pacific footballfish is one of over 100 species of anglerfish found around the world. Scientists know they typically dwell thousands of feet beneath the surface and lure unsuspecting prey into their mouths with the help from the flashy bioluminescent bulbs that dangle from their heads. They are covered in spikes and their sharp teeth are not used to chomp but to trap other fish, squid, and crustaceans that dwell in depths of up to 3,300ft, according to the California Academy of Sciences.
But this description applies only to the females. The males have evolved to become little more than sexual parasites that fuse themselves to their mates, losing all their internal organs – including their eyes – in the process. Connected for ever, the male retains only his testes to provide sperm in exchange for food.
The latest discovery, a female that measures about 15 inches and weighs 5.5lb, was in almost perfect condition aside from some slight scuffs and a small missing chunk probably caused by a curious seagull. She’s spiny but flabby, Frable said, and he could feel several big lumps in her abdomen. After X-rays and a quick peek inside, the scientists discovered she had sand in her belly. Most of the footballfish discovered wash ashore with completely empty stomachs.
It’s unclear if that is connected to their demise or if the fish just don’t eat very often. They are, after all, “just floating around in a giant black desert”, Frable said. The fish is now being preserved before undergoing more studies. “Specimens like this, every time they wash up, can provide additional clues.”
The other recently acquired Pacific footballfish, which was discovered in Orange county’s Crystal Cove in May, has already expanded scientists’ understanding of the species. It was also on display for several months this year at the Natural History Museum in Los Angeles, which enabled members of the public to catch a glimpse of the unusual creature. William Ludt, the assistant curator of the ichthyology collection at the Natural History Museum, said the exhibit fueled excitement about the find.
“There’s a lot we don’t know about this species in general,” he said. “It is exactly the type of thing we want to put on display so people can see it and learn about the world around them and about the strange creatures that are in their own backyard.”
That’s also why it is so important that anyone who encounters an animal on the beach alert officials who can get it into the right hands. Each one has the potential to provide a piece of a puzzle scientists are trying to solve. “Each one of these that comes up is a treasure trove of information,” Ludt said.