The deep ocean is full of oddities , frommagnetic field - sensing bacteriaand otherstrange microorganismstomassive squidand even “ murphy ” . The depths of the sea off the glide of New Zealand host something peculiarly curious , or at least they did until recent research exposed its origins : the unexplained “ hoofprints ” scattered across the seafloor are in reality the work of some crafty fish .
First discovered in 2013 , the mystery marks have mystify scientists ever since . They were found more than 450 meters ( 1,476 foundation ) deep in Aotearoa New Zealand ’s water by researchers at the area ’s National Institute of Water and Atmospheric Research ( NIWA ) .
The team has now analyzed their original footage and , after much drumhead scratching , have come up with an explanation for the cryptic markings , which unfortunately does n’t involve a small underwater horse .
The seafloor bitemarks match the head shape of two species of rattail.Image credit: Stevens et al., Deep Sea Research Part I: Oceanographic Research Papers, 2023
The culprits , they believe , are mysterious - sea rattails , also known as grenadier ( Coelorinchus ) – some specie of which have a pointed snout that looks suspiciously like the peculiar seafloor print .
“ We wondered if these grading could be traces of a rattail forage in the deposit for its next meal , ” NIWA ’s Darren Stevens said in astatement .
“ These types of rattails have a long schnoz and an extendable mouth on the underside of their head that allow for them to feed off the seafloor , something that other coinage do not . ”
To investigate , Stevens overlaid image of rattails ’ uniquely shaped heads with snaps of the seabed impression , finding , to his surprise , that they fit together perfectly .
“ I had a intuition this might work but I was really surprised how well the head profile epitome matched the mental picture . We were able to provide fairly good evidence that these impressions were made by two grenadier mintage , ” Stevens added , before going on to explain how this discovery could be crucial for our savvy of rattail species by identifying alimentation areas and critical habitat .
It is also the first time that their raw foraging behavior has been document , the team believe , revealing priceless selective information about how they hunt . It is thought they get hold of the seafloor in a read/write head - down billet , which may involve a “ unretentive salvo of stop number ” , before sucking up deposit and dribble it for their prey , the squad writes in a paper presenting their findings .
project such flummox patterns in the mystifying sea is by no means slowly , lease alone attempt to work out what caused them . In this case , the squad was capable to do so by using the Deep Towed Imaging System ( DTIS ) to permit them to see the seafloor in especial particular , study author Sadie Mills excuse . However , most of the time , pinpointing what ’s responsible for for anything unusual is impossible .
“ It is so coolheaded to finally have the establishment that what we view on the television was actually rattails feeding in the clay . It ’s like getting a nice reward at the end of many geezerhood of watching DTIS footage , ” Mills said .
This is n’t the first time that tricksy deep sea critter have trip a nautical mystery : hungry crustacean were found to be the architects ofcurious holesat the bottom of the Bering Sea , and thesestrange octagonsstamped across the Davy Jones of the Fram Strait were the work of feeding octopus .
The field is published inDeep Sea Research Part I : Oceanographic Research Papers .
