TechRare megamouth shark discovery sheds new light on marine life in the Philippines

Rare megamouth shark discovery sheds new light on marine life in the Philippines

The great white shark washed up on the beach.
The great white shark washed up on the beach.
Images source: © ILF Science | dr Glenn Moore

6:07 AM EST, December 7, 2023

An extraordinarily rare event occurred recently in the Philippines, as the sea cast up rarely seen sharks on the shores. Among these was a pregnant individual, identified as a representative of the megamouth shark species. This occurrence is unique in recorded history and serves as irrefutable evidence of the ovoviviparous nature of this species.

The twin discoveries took place in Dipaculao, situated on the Philippine island of Luzon. While one of the beached creatures was a juvenile, it was the gargantuan pregnant female that caught the world's attention.

Enigmatic titans of the deep

Megamouth sharks are marine oddities whose existence was unknown to us until less than 50 years ago. Researchers have had few opportunities to study these formidable creatures that can weigh up to 2679 pounds and have been observed only around 120 times in history.

These elusive swimmers are typically found in the tropical regions of the Pacific, Atlantic, and Indian Oceans. The life of a megamouth shark is predominantly hunting-based. They tail schools of fish, residing at depths of several thousand meters (miles) and only sporadically venture to shallower waters.

Pregnant megamouth shark found on Philippine shore

Mid-November marked a significant shift in history in the Philippines. Among the deceased sharks discovered was a female not only accompanied by one young one but also bearing six more within her. This event marks the first recorded discovery of a pregnant megamouth shark.

Her remains have been preserved and are set to be included in the collection of the National Museum of the Philippines. This find provides the first tangible evidence that megamouth sharks exhibit ovoviviparity. Scientists anticipate unveiling further insights about the physiology and lifestyle of this enigmatic shark species through ongoing examinations.

The cause of the shark's death remains uncertain, yet it raises many questions. Most known observations of megamouth sharks have been creatures victimized by accidents involving fishing equipment. Occasionally, they become stranded on a sandbank and, unable to return to deeper waters, succumb to starvation.

Investigators examining the carcasses found no perceptible injuries indicating any contact with boats or fishing gear. Furthermore, there were already fully hatched young ones inside the female, each measuring several dozens of centimeters (inches). This is an anomaly, as most other shark species tend to lay eggs or give birth primarily under stress. As there were no visible injuries on the female, it's unclear if she was under any duress to necessitate giving birth.

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