When you purchase through golf links on our site , we may earn an affiliate commissioning . Here ’s how it work .
sizable coral Reef , known for their brightly colored bristled and soft layer , may play as decisive refuges and food sources for thirsty sharks swimming through Australia ’s Great Barrier Reef , reports a novel 10 - twelvemonth study that captured underwater footage of shark .
Coral reef address just about 5 percent of the habitats inthe Great Barrier Reef , but about 95 percentage of the shark sightings happened near the reef , the report get hold .
A blacktip reef shark, known by the black tips on its fins, swims in Australia’s Great Barrier Reef.
" Sharks need tidy reef , " Mario Espinoza , the study ’s lead research worker and a Ph.D. nominee in environmental skill at James Cook University in Queensland , Australia , tell Live Science in an email . " It ’s a simple but powerful message . "
Beginning in 2000 , researchers deploy more than 2,500 outside submerged picture stations in the Great Barrier Reef Marine Park to document its maritime biodiversity . In all , the research team document 21 shark coinage . [ Great Barrier Reef Sharks Take The ' Cam ' Bait | television ]
" It ’s a fab paper , " say Demian Chapman , an assistant professor of marine biological science at Stony Brook University on Long Island , who was not call for with the study . " It ’s one of , if not the largest , the most comprehensive studies of its kind . "
The baited camera station reach depths of between 23 and 377 feet ( 7 and 115 meter ) — deeper than most diver studyingsharks , Chapman said . The method also go away the sharks alone , except for giving them a free snack of crush unctuous sardius .
" It was completely unnoticeable to the shark , because it was all done with cameras , " Chapman said . " Other studies catch shark . "
shark look in footage from 614 of the station and in about a quarter of the videos , a percentage like to other studies , such as one Chapman did in Belize , he said . " They aretop predatorsand they move around a lot , " he say .
The recording also prove what type of habitat the sharks preferred . For each video , the investigator noted the proportion of coral cover , plants and alga , filter feeder such as one dollar bill and sponges , delicate coral and bleak sand or mud , Espinoza say . They also assess coral complexness , or the topographical conformation and sizes of the reefs . [ On the verge : A Gallery of Wild Sharks ]
" For model , some land site that had more coral cover and that were more complex usually had more sharks than those that were all flaxen and soggy without any live cover , " Espinoza said . " situation with more coral also tend to have more Pisces the Fishes , and more fish means more solid food [ and ] resource for shark . "
No fishing
The researchers also regard more sharks in areas that were closed to angle . However , many shark species still preferred surface area with in high spirits coral cover within these protect areas , suggesting that both no - fishing zones and healthy coral reefs are vital for improving shark numbers , Espinoza suppose .
" This is in particular of import because late finding from a study publish by scientist at AIMS [ the Australian Institute of Marine Science ] had showna 50 percent decline in coral cover on the Great Barrier Reefsince 1985 , " Espinoza said . " This large diminution of coral cover is potential to have negative outcome on a wide-cut range of nautical specie , including shark population . "
The Great Barrier Reef no - sportfishing zones install in 2004 , as well as other marine direction rule , such as enforcing catch boundary and apportion sportfishing licenses , may helpthreatened shark speciesrebound , the researcher said .
A few years after the no - fish zones went into upshot , the identification number of grey sharks increased , read Marc Nadon , a fishery appraisal specialist at the University of Hawaii , who was not take with the study . But the zone did not appear to assist thetiger shark species(Galeocerdo cuvier ) , which swim long distances and often leave protect areas , he said .
Nadon take down that the underwater photographic camera record more shark farther from the Australian coast . " To me , it seems like it ’s a factor of isolation , " Nadon said . " The farther out you are from people , the more sharks you have . "
shark are often demonise in pop culture , but field of study like this remind the public that sharks are needed in the sea , said Simon Pittman , managing director of Seascape Analytics , a maritime consulting troupe , and a scientist with the U.S. National Oceanic and Atmospheric Administration ’s biogeography branch , who was not need with the written report .
" We need to remember as ecologists that shark are top predators , and they ’re key to maintaining ecosystem integrity , " Pittman said . " you may see them as canaries in a coal mine . They ’re sensitive to how we wangle the arrangement . If we ’re overfishing , not only are we contain sharks themselves , but we ’re get hold of the intellectual nourishment of the sharks . "
next studies may define just how shark interact with coral reefs and other habitat they frequent , expert said .
" It could be that you need a healthy reef to have sound shark population , " Chapman said . " Or some the great unwashed say you need sharks to have a healthy reef . Whether it ’s the chicken or the testis , we do n’t know in this font . "
The study was release today ( Sept. 10 ) in the journalPLOS ONE .
