The Tresher shark
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| Malapascua - Philippines - June 2017 |
The pelagic thresher (Alopias pelagicus) is a species of thresher shark, family Alopiidae; this group of sharks is characterized by the greatly elongated upper lobes of their caudal fins. The pelagic thresher occurs in the tropical and subtropical waters of the Indian and Pacific Oceans, usually far from shore but occasionally entering coastal habitats. The smallest of the three thresher species, the pelagic thresher typically measures 3 m (10 ft) long and about 70 Kg weight.
Malapascua - Philippines - June 2017
Malapascua is about the only place in the world where recreational divers can encounter Thresher Sharks on a near daily basis. Thresher Sharks are natural deep dwellers, spending the vast majority of their time at depths well below recreational (40 meters) and often Technical diving limits (deep dive world record by the Egyptian Ahmed Gabr at 305 meters - more than 1000 feet).
In Monad Shoal dive site in Malapascua you can go see these incredible animals everyday at 5 am while they come around 30 meters deep for an early morning cleaning session of the parasites they have on their body.
Because they live so deep, tresher skarks adapted to their very low light environment, this is why they have such big eyes to see in the dark. For this reason it is strictly forbidden to bring any kind of artificial light during these dives, cause we don't want to scare them.
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| Malapascua - Philippines - June 2017 |
The diet of the pelagic thresher consists mainly of small midwater fishes, which are stunned with whip-like strikes of their tails. Along with all other mackerel sharks, the pelagic thresher exhibits ovoviviparity and usually gives birth to two babies.
The developing embryos are oophagous, feeding on unfertilized eggs produced by the mother. The young are born unusually large, up to 43% the length of the mother. Pelagic threshers are valued by commercial fisheries for their meat, skin, liver oil, and fins, and are also pursued by sport fishers. The International Union for Conservation of Nature (IUCN) assessed this species as Vulnerable in 2007.
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| Malapascua -Philippines - June 2017 |
Just as a reminder, the year 2011 saw a reported 12 shark deaths worldwide, the most since 1993, according to National Geographic.
By contrast, a new report estimates that humans kill about 100 million shark every year. Yes !!!
The scientists official estimation is between 63 million and 263 million sharks every year.
The reason? overfishing. And the fact that shark are almost not protected in the high sea.
If this situation continues, it could drive many shark species to endangerment or even extinction.
If you wanna learn more about this, I invite you to look at Rob Stewart documentary called "Sharkwater"
The Shark conservation society
The Pew trust - Global shark conservation
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