Spineless urchins warning
Anglers argue that shark conservation has been too effective , as increasingly their catches are being intercepted . What ’ s really going on , asks Shark Trust MD Paul Cox
Spineless urchins warning
Surveys in the Red Sea have indicated a rapid reduction in numbers of the black sea urchin , thought to play an important role in controlling algae and keeping coral reefs balanced .
To date , the reefs of the Red Sea have shown a remarkable resilience to warming sea temperatures , with ancient hard coral reefs such as the Fury Shoal and St John ’ s still in excellent condition . However , to the north near the city of Eilat , Israeli researchers have reported a startling drop in the numbers of black sea urchins . Recent surveys show a 90 per cent reduction in the Jordanian port of Aqaba , in addition to similar disappearances across Egypt and Saudi Arabia .
The phenomenon has been attributed to a new pathogen that paralyses the urchin ’ s spines and tiny feet . Eventually , necrosis sets in , leaving a bare skeleton . Without their spines , infected urchins are soon eaten by fish . The urchins play a key role in grazing algae from the reefs and thus keeping the coral clean , so losing them could have a profound effect on Red Sea corals if the trend continues .
Victims of our own success ?
Anglers argue that shark conservation has been too effective , as increasingly their catches are being intercepted . What ’ s really going on , asks Shark Trust MD Paul Cox
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report that I came across this month on ABC news from Australia , hints at the next stage in shark conservation as we gradually work towards successfully implementing better fisheries management for sharks . Are we going to come to a point where we ’ re so successful that we end up with ‘ too many sharks ’?
We know that the primary threat to sharks and rays is overfishing . One-third of the world ’ s species are threatened and in every single case , the problem comes from fishing . So , when fisheries are controlled , as around Australia , populations can start to rebound . That should be a good thing , but not everyone agrees .
Anglers in Australia are now concerned that they face more and more cases of depredation – essentially sharks taking fish off the hook from anglers . One fishing charter operator claimed that he ’ s experienced trips where only one in ten of the fish caught get past the sharks . This is obviously bad for business and spoils a day out for recreational anglers . It also messes up stock management as the catches taken by sharks can ’ t be logged . So , what ’ s going on ?
It ’ s possible that the reports of ‘ out of control ’ depredation are caused by an excess of sharks , or a wider imbalance in the system as bait fish are removed while predators are protected . That ’ s a challenge for fisheries managers . Keeping everything in balance , especially if a lack of data means that they find themselves working ‘ blind ’.
But there could be other explanations . Research on sharks ’ responses to underwater sound and to their behaviour around baited traps suggests that some species quickly learn to adapt to a free meal . So , the sound of a slowing boat engine , or the sniff of bait acts like a call sign . And they quickly learn where the popular fishing spots are . So maybe not so much more sharks , but smarter sharks .
There ’ s also the effect of social media . Anecdotal accounts of increasing losses to sharks are amplified and this can affect our perception of the issue . So , getting to the bottom of the issue isn ’ t straightforward . Anglers , scientists and fisheries managers need to work together . Sightings and catches need to be recorded , populations need to be monitored and , crucially , fisheries need to be managed for sustainability .
Sharks and rays are an intrinsic element of a bigger system . Conservation is never as simple as we might hope . There will always be another challenge . As we see on land , where wildlife and human interests come into conflict , so we may see more of this at sea in the years to come . www . sharktrust . org
( SFF ), which represents the country ’ s fishermen ’ s associations , has warned the plans could have a “ catastrophic impact ” on the industry .
The Scottish government will now consult further with the industry , communities and conservationists about a new approach .
However , groups that wish to pursue community-led marine protection in their local area on a quicker timescale , such as those initiatives in Lamlash Bay on Arran , will be supported to pursue their plans .
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