Watch Over Antarctic Waters

Watch Over Antarctic Waters

COMMENT PANDEMICS Invest in screening CONSERVATION Krill, orca and PHYSICS Has the pursuit of OBITUARY Stanley Falkow, people for infections, not whales: three tales of ocean beauty led modern physics microbe-mechanism animals for viruses p.180 plunder p.184 into a morass? p.186 hunter, remembered p.190 /GETTY NATIONAL GEOGRAPHIC NATIONAL PAUL SUTHERLAND/ PAUL Wandering albatrosses follow a vessel as it fishes for toothfish. Watch over Antarctic waters In a rapidly changing climate, fisheries in the Southern Ocean must be managed cautiously in response to data, warn Cassandra Brooks and colleagues. ntartica is a “natural reserve, devoted are strict, precautionary and science-based. currents and weather patterns are changing3. to peace and science”, according to Nations that are signatories must avoid The northwest coast of the Antarctic Pen- the Antarctic Treaty System. This significant or irreversible damage to fish and insula is one of the fastest-warming places Acomplex set of agreements collectively takes other animals that depend on them. on Earth — summer mean temperatures a firm stance on conservation, exemplified But the convention is failing to protect the are on average 3 °C higher than they were in by the Convention on the Conservation of Southern Ocean from overfishing and the 1950. Diminishing sea ice also means fewer Marine Living Resources. Adopted in 1980, impacts of climate change. algae, krill and Antarctic silverfish (Pleura- this convention was negotiated rapidly in Up to 20 nations fish in these icy waters1. gramma antarctica). Cumulative impacts of response to expanding trawling of Antarc- Antarctic krill and Patagonian and Antarctic historical and current fishing combined with tic krill (Euphausia superba). Krill are at the toothfish (Dissostichus eleginoides and environmental change have been linked to base of the region’s marine food web, so there Dissostichus mawsoni) are the main quarry. declines in populations of Chinstrap4 and were worries that a dearth of the small crus- More vessels and more-efficient fishing Gentoo penguins5 (Pygoscelis antarctica and taceans would threaten the whole ecosystem, technologies are now able to catch more ani- Pygoscelis papua). especially whales. mals (see ‘Antarctic fisheries’). Vessels using Because of the convention’s strict The aim of the convention is to conserve vacuum pumps can suck up 800 tonnes of provisions, its 25-member implementing all biota and ecosystems in the Southern krill in one day2. The vessels compete with body — the Commission for the Conserva- Ocean. Although fishing is allowed, it is not birds and mammals for food, especially in tion of Antarctic Marine Living Resources a right and does not trump responsibility for the most accessible waters. (CCAMLR) — is widely seen as a leader conservation. The convention’s provisions At the same time, ocean temperatures, in high-seas fisheries management. ©2018 Mac millan Publishers Li mited, part of Spri nger Nature. All ri ghts r14ese rJUNEved. 2018 | VOL 558 | NATURE | 177 COMMENT But some fishing states are now trying to weaken the convention’s rules. China, An emperor penguin CCAMLR’s newest member (as of 2007), and an ice-breaker in argues that the convention enshrines the Ross Sea. nations’ rights to fish, rather than a respon- sibility to conserve6. China has also insisted that no-fishing zones are contrary to the convention, even though they are expressly included. And it has proposed that scientific evidence of a threat is required before an area is closed to fishing. Some other fishing nations, such as Russia, support this view7. Because CCAMLR operates by consen- sus, any state can block a measure that it perceives is not in its interests. For instance, in 2011, South Korea prevented the black- listing of one of its vessels that was caught fishing illegally8. If fishing carries on at its current pace amid rapid climate change, prime Antarctic fisheries and marine ecosystems could col- lapse, as has happened elsewhere9. For exam- ple, in the 1990s, after politicians failed to act on scientists’ warnings, the abundance of Atlantic cod (Gadus morhua) declined to less than 1% of historical levels9. We urge CCAMLR to better protect fisheries in the Southern Ocean. The impacts of climate change on populations now and in the future should be factored into decision- making, to avoid crashes in populations. CCAMLR may need to reduce or stop fish- Southern Ocean (see ‘Antarctic fisheries’). to increase its toothfish catch and send its ing in threatened areas or where there is high Owing to high prices, this is lucrative. Exploi- fleets into unfished areas such as the Weddell uncertainty about adverse effects. Marine tation rocketed in the 1990s, when toothfish, Sea5. Ukraine wants to capture more krill5. reserves must be well designed, and more of rebranded as Chilean sea bass, became popu- New Zealand and Australia, among others, JOHN B. WELLER them must be implemented. lar in top restaurants. Illegal, unreported and have extended their reach into toothfish CCAMLR should also do more to sup- unregulated fishing soared and ravaged popu- areas1. Other nations, including Namibia port basic research that is independent of lations; illegal fishers took six times more fish and Uruguay, signed the convention to gain the fishing enterprise. Such studies will lead than did legal vessels11. CCAMLR turned this fishing and market access1. to greater understanding of the dynamics of situation around by documenting catches, targeted species and their vulnerabilities to monitoring vessels and black-listing those KNOWLEDGE GAPS environmental change and overfishing. that did not comply. Illegal catches fell from Climate change compounds the problem. 33,000 tonnes in 1996 to less than 2,000 tonnes But environmental effects are difficult to FISHING PRESSURE by 2007 (ref. 11). Nonetheless, many Patagon- disentangle from the consequences of fish- Antarctic waters have long been plundered ian toothfish populations crashed, and remain ing. For example, scientists do not know (see also page 184). Species driven almost to depleted, notably whether toothfish fishing or encroaching ice extinction include elephant seals (Mirounga those around the “Some scenarios is behind the changing prevalence of killer leonina), blue whales (Balaenoptera muscu- Prince Edward may require whales in the southern Ross Sea12. lus), king penguins (Aptenodytes patagonica) Islands, BANZARE reduced More data would help. But research in the and marbled rockcod (Notothenia rossii)10. Bank and Kerguelen catches, or Southern Ocean is difficult and expensive. Some have bounced back; others haven’t, Plateau. allocations that Much of what is known about toothfish is such as the rockcod. Even so, remoteness The life cycles are restricted, gathered by the fishing industry, which does and harsh conditions have protected animals of toothfish make temporally or not collect environmental data. There are in the seas around Antarctica, in comparison them particularly spatially.” many gaps. We have much to learn about with those elsewhere. vulnerable, as well the life histories and population dynamics In the Southern Ocean, more krill are as difficult to study. They mature late, grow of the species being caught and how environ- caught than any other species (by weight). slowly and can live for 50 years. No one mental changes affect their birth and death About 300,000 tonnes are caught annually. knows how many there are in the Ross Sea, rates. There are few quantitative studies of They are mainly destined for omega-fatty- the main international fishery for tooth- connections among targeted organisms in acid supplements and fishmeal. Most krill fish. Nor does anyone know when, where the food web. are caught off the Antarctic Peninsula. The or how often they spawn9. They are the top The long-term ecological research (LTER) industry says that such catches are small, fish predator in the Southern Ocean, and programme, based at Palmer Station on the compared with the more than 300 million they are also key prey of Weddell seals (Lep- west of the Antarctic Peninsula, is unparal- tonnes of krill estimated to reside in circum- tonychotes weddellii) and killer whales (Orci- lelled in its multi-faceted approach. It gathers polar waters2. nus orca), and compete for smaller fish with information, for example, on how fluctuat- Patagonian and Antarctic toothfish each Adélie penguins (Pygoscelis adeliae). ing sea ice influences krill and other small support relatively small fisheries in the Fishing states want more. Russia is trying organisms. CCAMLR also has an ecosystem 178 | NATURE | VOL 558 | 14 JUNE© 20182018 Mac millan Publishers Li mited, part of Spri nger Nature. All ri ghts reserved. ©2018 Mac millan Publishers Li mited, part of Spri nger Nature. All ri ghts reserved. COMMENT South Atlantic CCAMLR Ocean Managed area Prince Edward Islands Sub-divisions South Georgia Marine protected areas NUMBER OF VESSELS South Sandwich Islands REQUESTING TO FISH 16–20 11–15 Krill shoals are 5–10 especially rich near the coasts of the <5 Weddell Western Antarctic Sea Peninsula, which is one of the fastest- Kerguelen warming regions Islands on Earth. TOTAL ALLOWED ANTARCTICA CATCH (TONNES) Davis Sea Krill 2.6m Ross 1,000 km Sea 440k 279k 155k Fishing pressure is 93k South Pacic increasing in the Ross Ocean Sea (for toothsh) and o the Antarctic Toothsh Peninsula (for krill). 5k monitoring programme designed to study ANTARCTIC FISHERIES 2.6k–3.5k krill-fishing impacts on land-breeding marine Krill and toothsh received the largest catch allowances in the Southern Ocean in 545–1.3k predators. However, these data are not effec- 2017–18. They are increasingly exploited in spite of tight management by the tively incorporated into decision-making. Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). 38–63 CCAMLR acknowledges that it must account for the impacts of global warming are making the area more accessible. In 2017, fishing can continue and still meet the SOURCE: WWW.CCAMLR.ORG in its policies.

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