In a recent survey by the National Institute of Hydrosphere and Atmospheric Research (NIWA), their scientists went to an offshore area near New Zealand’s South Island to conduct a census. for the hoki, a local fish, the white meat and specialty of the country’s export.
The goal of the scientists at NIWA: They will drop nets to a depth of 1,200 meters in multiple locations, collect and tally the number of hoki fish caught in the net, and then combine the numbers together into a map, model. estimate the entire population of this fish population on the South Island.
However, in a net pulling, by chance, scientists found a strange creature. It looked like a young naked rat, with large eyes and two fins resembling two wet chicken feathers attached.
Through its almost transparent skin, the researchers saw a yellow liquid. This made NIWA aquatic scientist Brit Finucci immediately know they had found a rare specimen: It was a ghost shark, a newly hatched ghost shark, to be precise, from an egg.
“You probably know it, because the golden yellow thing in its belly is the yolk, or the yolk of an egg“, Finucci said. Normally, ghost sharks will lay eggs all the way to the bottom of the sea. The egg embryo is completely in the yolk, and they will eat the egg yolk until it hatches.
It is not known why this young ghost shark can swim up to a depth of 1,200 m. “Most of the deepwater ghost sharks that humans have encountered so far are adult fish, newborns are not often reported, so we know very little about them.”Finucci said.
Rare footage of ghost sharks
But what exactly is a ghost shark? Why does it have such a name? The images from the video above can allow you to imagine the first time scientists have seen it on the deep sea floor.
The fish appeared in front of the camera like a pale ghost. It had the body of a withered shark, its body covered with stitches-like marks, and its eyes were white. The fish swims but its appearance does not exude any vitality.
In fact, ghost sharks are not really sharks. It belongs to one of 50 species of ratfish that have been discovered, a cross between a shark and a ray. All these ghost sharks are therefore boneless. The entire skeleton system that keeps them strong is actually just cartilage.
The first video of this fish was filmed in 2000. But it was not until 2002 that a team of scientists first described it in the journal Cybium. The ghost shark has since officially had a scientific and recognized name: Hydrolagus trolli – the name is in honor of Ray Troll, an Alaskan artist who often helps scientists draw illustrations of animals marine animals they discovered.
Lonny Lundsten, a senior researcher at the Monterey Bay Aquarium Research Institute (MBARI) in California said: “It was an odd-looking fish with a pointed snout. It had a long, tapered and well-pointed tail, relatively large eyes, and it was almost grey-white.”
Ghost sharks are quite small compared to real sharks. They are only 60-90 cm long, but live in very deep waters, from 1,600 m down to more than 2,000 m. Ghost sharks often reside on seafloors that are rocky instead of soft sediments.
The earliest fossils of this fish’s ancestor have been found by paleontologists between 350 million and 375 million years old. That means ghost sharks were present on Earth before the age of dinosaurs.
Today, ghost sharks are occasionally found off the coast of Australia, New Zealand and New Caledonia. However, when caught in the nets of fishermen and brought back to the mainland, most of them died. A total of 23 ghost shark specimens were collected and stored, but all were adult fish.
Never before have scientists found a newborn ghost shark like this one. So they are very careful about the opportunity to study it.
Scientists at the National Institute of Hydrosphere and Atmospheric Research (NIWA) plan to conduct genetic testing to determine the exact species of this ghost shark. Scientists have now discovered more than 50 species of ghost sharks in all.
There are a few interesting characteristics that attract them in these fish. In addition to their pale appearance and coloration, ghost sharks often have white birthmarks on their skin that look like post-surgery suture scars.
Scientists say they are actually the radar antennas of this fish. The suture-shaped white birthmarks are concentrated mainly on the head, allowing the ghost shark to sense every tiny vibration of the surrounding water.
Ghost sharks can use that skill to hunt. But until now, the diet of ghost sharks from childhood to adulthood is still something that scientists have to study.
With the discovery of a young ghost shark, with its yolk still on its stomach, scientists at NIWA are now able to shine a light on this strange fish.
Refer to Sciencealert, Livescience