The mother shark aborted her dead young and washed up on a UK shore

 

The examination of the carcass of the elusive shark revealed that it had not reached its full maturity.

The conclusion reached by specialists is that a baby shark washed up on a beach in the United Kingdom had most likely been aborted by its mother before it was due to be born.

According to a report published by the local news organization Bournemouth Echo, Georgina and Tim de Glanville discovered the dead shark on Southbourne beach in Bournemouth, southern England, on May 13. (opens in new tab). It was determined to be a common thresher shark (Alopias vulpinus), which, despite being very widespread in the waters of the United Kingdom, is not often sighted. The shark's body was recovered by a group representing the local council. Then it was taken to be examined by specialists.

According to Georgia Jones, a conservation ecologist at Bournemouth University who performed an autopsy on the shark's bones, "It was a pretty significant surprise to hear that a thresher had washed ashore." This information was shared with Live Science. Locally, a few have been caught and released, but this is the first one that has washed ashore.

Typical threshing machines can reach up to 20 feet (or 6 meters). According to Jones, a significant portion of their length comprises their long, crescent-shaped tails, which they whip through the water to startle their prey. She went on to say that thresher sharks are notoriously difficult to spot close to the coast of the United Kingdom since they prefer to live in deeper seas.

According to a Twitter thread(opens in new tab) by Jones, the length of the fetal shark was approximately 3 feet (0.9 m), which is slightly shorter than the average body length of a newborn thresher shark. The shark was identified as a female due to the absence of claspers, a shark's equivalent of a penis.

Jones stated that the shark's small size and the presence of other anomalies, such as the lack of front teeth and the absence of growth rings in the shark's vertebrae, are all indications that the pup may have been aborted by its mother. Other anomalies include the absence of growth rings in the shark's vertebrae. "Abortion is more common in sharks, rays, and skates than was previously acknowledged," and it has been observed in species closely related to thresher sharks, she added. "Abortion is more common in sharks, rays, and skates than was previously known."

The Chondrichthyes are a group of fish distinguished by the presence of a skeleton comprised of cartilage rather than bone. This group includes sharks, rays, and skates. Abortions in Chondrichthyes are much more common than was previously believed, according to a study released in 2018 and published in the journal Biological Conservation (opens in a new tab). These abortions may be triggered by high-stress situations such as being chased by a predator or being caught by humans, may be triggered by high-stress situations. Abortion rates, on the other hand, can vary widely vary depending on the species.

According to Jones, in the case of the deceased thresher shark, it is plausible that the mother may have been prompted into having an abortion after being mistakenly caught by anglers, referred to as bycatch. She went on to say that bycatch is one of the primary reasons threshers are included on the International Union for the Conservation of Nature's (IUCN) Red List of species threatened with extinction .

Jones had the opportunity to investigate the physiological characteristics of thresher sharks during the autopsy that he performed on the premature shark. Most sharks have an ectothermic, or cold-blooded, metabolic system, but thresher sharks have an endothermic, or warm-blooded, metabolic system. This means that thresher sharks have different muscles and a more sophisticated blood artery system than most other sharks. According to Jones' explanation, thresher sharks are endothermic, which allows them "a warm brain and eyes so that they can operate remarkably well in cooler water," which also improves their swimming performance.

The southern coast of the United Kingdom is a thresher shark hot spot because the area is part of an important migration route for the species. According to Jones, the shark mother may have been migrating along this path when she had an abortion on her newborn pup. On the other hand, it is not quite obvious where the shark that was found dead came from. Jones speculated that the puppy had been in the water for several days and could have floated to the Bournemouth shore from a great distance because its stomach and liver had already been removed by scavengers when it washed up on the beach. Additionally, a portion of the pup's iconic tail had also been removed by scavengers.

Article source : https://www.livescience.com/aborted-thresher-shark-uk-beach

Image source : https://pixabay.com/id/photos/hiu-ikan-laut-bawah-air-akuarium-164899/

# The dead baby shark that washed up on a beach in the UK most likely did not survive because its mother had aborted it.

# A dead baby shark found on a British beach was probably aborted by its mother.