Based on biomass , more sharks live in the waters surrounding the northernmost island of the Galapagos archipelago than anywhere else in the world . The island of Darwin and Wolf are home to 11.2 tonnes ( 12.4 tons ) of shark per hectare ( 2.5 Akka ) , according to new findings published inPeerJthis week . The findings will avail inform the government of Ecuador as it modernise the“no - take ” reservethat was just announced in March .
Overfishing has consume shark and other top predatory fish population around the public , reducing their biomass by more than 90 per centum . Now , one in four species of gristly Pisces the Fishes is threatened with extinction because of overutilisation and habitat deprivation . Even distant locale have been hard impacted . There are , however , a few hotspot for shark rest : Costa Rica ’s Cocos Island National Park , Chagos Marine Reserve in the Indian Ocean , and Darwin and Wolf in the far north of the Galapagos Marine Reserve .
Darwin and Wolf are the tops of eroded , nonextant submerge volcanoes . These modest island , located less than 40 kilometer ( 24.8 Roman mile ) apart , are hard charm by the warm Panama current that add up from the nor'-east . Unlike other island in the archipelago , which is dominated by the cold equatorial counter - current , the waters of Darwin and Wolf range from 22.5 to 29 ° ampere-second throughout the year .
During November of 2013 and August of 2014 , a team led by Pelayo Salinas de León from the Charles Darwin Research Station conducted two expedition to Darwin and Wolf to estimate the abundance of shark and predatory fish assemblages . The squad surveyed the fish at seven sites around the two islands using traditional visual censuses as well as a plunger - operated stereo - TV system equipped with cameras .
Their estimate revealed the largest Rand fish biomass ever reported : 21.7 tonnes ( 24 tons ) per hectare at Darwin and 11.4 tonnes ( 12.6 wads ) per hectare at Wolf , or 15.9 tonne ( 17.5 tons ) per hectare on average . And 73 percent of the entire biomass ( or 11.2 tonne per hectare ) was shark , admit scalloped hammerheads , Galapagos sharks , and blacktips .
The presence of sharks and top marauder indicates a level-headed marine ecosystem . But the squad also found low amounts of predatory Rand Pisces the Fishes such the leatherbass and sailfin grouper . These long - live fish grow slow , make up them especially vulnerable to overfishing . Despite being part of the Galapagos Marine Reserve , the two northern islands were n’t fully protect until the declaration of theDarwin and Wolf Marine Sanctuaryin March 2016 .
