Discovery of floating bottle carrying crustacean hitchhiker helps researchers learn more about the impact of plastic pollution on marine life
Scientists were investigating juvenile fish off the coast of Okinawa when they discovered a plastic bottle floating in the sea. They were surprised to discover that something very unusual lived inside.
“(To my surprise) a large live swimming crab… bad luck“The crab was trapped inside the bottle,” Hajime Sato and Yoichi Sakai, who discovered the crab, said in a statement. “The crab was clearly bigger than the mouth of the bottle!”
They wondered how the crab got inside.
When a bottle collected 500 meters off the coast of Sesoko Island in July 2022 was analyzed, traces of it being manufactured in November 2021, about eight months earlier, were found.
The bottle was open, but the crab was completely stuck, even though water was flowing in and out.
The diameter of the bottle mouth was 24mm, but the stranded creature was longer and wider. At 40.31 mm long and 88.23 mm wide, it’s too chunky to come out of the opening.
A large living, swimming crab, Portunus Sanguinolentus, is trapped inside a bottle. (Hajime Sato/Hiroshima University)
That’s probably how it came in, but how long has it been there? Sato and Sakai, along with their co-author, the late Tetsuo Kuwamura of Chukyo University in Nagoya, set out to solve the mystery and published their research results in a magazine. ecosphere.
At the time of this study, lead author Sato was a doctoral student under Professor Sakai at the Graduate School of Integrated Life Sciences at Hiroshima University, and is currently a postdoctoral researcher at Okinawa Institute of Science and Technology University (Okinawa Prefecture).
When they found the jar, there were four types of fry nearby.Canthidermis maculata)Sergeant Major Fish (Abdefduf vaigiensis)Rainbow Runner (Elagatis bipinnulata) and Freckle Drift Fish (Psenes Cyanofrith).
A bottle with algae and barnacles attached to it, the young fish collected with it, and a blue crab taken out of the bottle. (Hajime Sato/Hiroshima University)
“We hypothesized that this crab survived by hunting young fish in bottles,” the authors write in their study. Using DNA metabarcoding to analyze its stomach contents, we found evidence that it was feeding on triggerfish, sergeantfish, and green and brown algae.Ulva compression and strangulation of millionaire) may have been growing in a floating bottle.
High-density polyethylene (HDPE) Shaoxing wine bottles also contained goose barnacles (goose rabbit) grows on the outside. These were the keys to solving the mystery.
Knowing how fast these barnacles grew, scientists were able to estimate that the bottle had probably been floating in the ocean for 62 days.
“These results suggest that the crabs entered the bottle as larval or juvenile stages, survived with sufficient nutrition, and continued to grow in the bottle while drifting for approximately two months,” the study said. Eventually, the little crab was unable to escape and became completely trapped.
Scientists already know that plastic pollution can harm and even kill a variety of marine animals. Whales, sharks and marine mammals can become entangled in fishing nets, and turtles can die from eating plastic bags.
But the latest discovery shows that the harm extends to small creatures like this crab.
“Plastic bottles discarded by humans can trap crabs and prevent them from escaping,” the authors say. “Through this striking example, we want readers to realize that the items that make our lives easier can sometimes have unexpected effects on small marine animals.”
This isn’t the first time this crab-like animal has been trapped in a plastic bottle like this. “Similar cases have already been reported in waters near Japan,” the authors wrote, “suggesting that this was not an isolated incident.
Top image: Typical bottle of the sea © Getty
