Did you know that there is a shark called sofa shark? The false catshark (Pseudotriakis microdon) is a large (up to 9.8 ft -3 m- in length) shark that appears like a flabby brown-pink sofa. At least if you haul it on the surface.

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This 3-m-long false catshark was observed in Nihoa Canyon at 1,200 m depth. By NOAA Ocean Explorer, Public Domain

The also referred to as dumb shark is actually a, albeit mostly sluggish, predator and scavenger in its natural environment: at depths of 1,600–4,600 ft -500–1,400 m- all over the world. Due to its large oily liver, the sofa shark is able to hover, too. It feeds on bony fish, smaller sharks and squid and, as a AT&T deep-sea shark expedition off the Canary Islands 30 years ago proved (using deep-sea longlines to find the culprits damaging their communications cables), also on our waste: the stomach of one false catshark contained “a softdrink tin, a whole pear, several boiled potatoes and a pack of cigarettes”.

The sofa shark reproduces ovoviviparous, the gestation period lasts possibly two or three years. During that time the embryos feed first off a yolk sac and later off a vast amount of unfertilized eggs provided by the mother (oophagy), but they also use them to replenish their external yolk sac (which they later transfer into an internal yolk sac to serve as a post-birth food reserve). The sofa shark gives birth to only two (maybe up to four) 3.9–4.9 ft -1.2–1.5 m- long pups at a time.

Because of the vastly different conditions especially the water pressure compared to its natural habitat, hauling deep sea fishes to the surface is not a good idea. Even after throwing them back overboard (after catching them for scientific purposes or as by-catch) they most likely die. We should let the deep seas alone.

Sources: here and here

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