It faces the cumulative threats of commercial krill fishing, tourism, research infrastructure expansion and climate change. Our call comes ahead of a meeting, due in the next fortnight, of the international group responsible for establishing marine protected areas in the Southern Ocean. We urge the group to protect the region, because delays could be disastrous. Climate change threatens to unravel the Southern Ocean ecosystem as species superbly adapted to the cold struggle to adapt to warmer temperatures.
The impacts of climate change are especially insidious on the Western Antarctic Peninsula, one of the fastest-warming places on Earth. In February, temperatures reached a record high: a balmy The peninsula is also the most-visited part of Antarctica , thanks to its easy access, dramatic beauty, awe-inspiring wildlife and rich marine ecosystems. A map of the current and proposed marine protected areas under consideration.
Cassandra Brooks, Author provided. More than 74, cruise ship passengers visited last year, up from 33, in the season. The expansion of infrastructure to accommodate scientists and research, such as buildings, roads, fuel storage and runways, can also pose a threat, as it displaces local Antarctic biodiversity. While there's less ice, there are more people. Last year nearly 20, tourists visited the Antarctic Peninsula, according to the International Association of Antarctica Tour Operators.
There are also more researchers, and there is more exploration for minerals and other resources. An increase in visitors means more disturbances to the fragile ecosystem, more pollution and more opportunities to bring organisms onto the continent from elsewhere in the world.
These organisms could include invasive species that significantly affect delicately balanced ecosystems. An increase in boats means a greater chance of an oil spill in an area that would be very difficult to clean up. More than a dozen "vessel emergencies" have been reported in the Southern Ocean in the past six years, according to a study cited in the new paper. That includes a Chilean vessel that went down in carrying 50, gallons , liters of diesel. A Brazilian ship sank in April.
Robust tests of long-held theories of how the under-ice habitat sustains krill larvae require much more quantitative data—over time and over a wide scale—on larval abundance, distribution, and foraging behavior. But netting krill is not easy. Larvae tend to wedge themselves into nooks and crannies, defying divers' attempts to nab them while protecting their expensive nets— loaded with even more expensive electronic gear—from the ice.
Whatever is behind the correlation between sea ice decline and krill declines, the future of the Antarctic ecosystem hangs in the balance. A report by the Intergovernmental Panel on Climate Change predicted that the Antarctic Peninsula will experience some of the largest, most rapid climate changes on earth.
Concluding his testimony on climate change impacts, Fraser warned the US Senate committee that if future warming continues and the cycle of heavy ice years exceeds the life span of krill, the species will face a reproductive crisis. Our understanding has advanced light years since then, rendering such notions nearly quaint. Cherry-Garrard and his companions thought the forbidding Antarctic landscape immune to human assaults. Today, with this notion, too, proven false, one wonders if the damage can be reversed.
But the clock is ticking. If the Antarctic ecosystem collapses, it won't be because scientists were off on a misguided search for penguin eggs.
In , oceanographers Warren White and Ray Peterson identified significant inter-annual variations in the atmospheric pressure at sea level, wind stress, sea surface temperature, and sea-ice extent over the Southern Ocean. They called this system of coupled anomalies the Antarctic Circumpolar Wave. Heavy black arrows depict the general eastward motion of anomalies, while other arrows indicate communications between the circumpolar current and the more northerly subtropical gyres.
Download: PPT. Box 1. Retreating Sea Ice and Krill Declines In November , the most comprehensive study to date of krill distribution and abundance in the Southern Ocean reported a catastrophic drop in krill numbers. Figure 2. A Question of Sustainability A major issue in devising strategies to protect krill populations concerns the impact of krill fisheries. Further Reading and Information 1.
Nature — View Article Google Scholar 2. View Article Google Scholar 3. View Article Google Scholar 4. Accessed 14 February View Article Google Scholar 5. Climate change Climate change is the greatest long-term threat to the region. Some parts of Antarctica are experiencing significant ice retreat, including the collapse of ice shelves along the Antarctic Peninsula, while other areas are increasing.
If our climate continues to warm and acidify the Southern ocean, scientists predict that krill populations could be devastated, undermining the entire food chain. As global fisheries become depleted, there is growing interest to expand fishing throughout the region.
In particular, krill fishing needs to be closely monitored and controlled to ensure whales, penguins and other wildlife are protected. Illegal, unregulated and unreported IUU fishing also threatens fish stocks in some areas of the Southern Ocean and thereby the seabirds and marine mammals that depend upon them.
The harmful fishing methods used by IUU fishing vessels also cause the direct deaths of countless seabirds. Marine pollution Persistent organic pollutants POPs have been measured around Antarctica and detected in wildlife.
Microplastics are emerging as a threat in the region. Increasing quantities of plastic are washing up on the Antarctic coastline and sub-Antarctic islands. Invasive species Many Antarctic species have evolved in isolation from the rest of the world.
Consequently, they have developed no means of defending themselves from the invasive species carried aboard ships. WWF catalysed and helped fund the removal of rabbits from Macquarie Island and is now helping to remove mice from the Antipodes Islands.
The international commission which decides on conservation plans for the oceans surrounding Antarctica has once again failed to deliver increased prot Satellite tracking is unlocking the mystery of exactly where humpback whales feed on krill, highlighting the need for increased protection of the West We acknowledge the Traditional Custodians, whose land we work upon and we pay our respects to their Elders past, present and emerging.
At WWF, we work in Australia and in our Asia-Pacific backyard to protect endangered species and habitats, meet the challenge of climate change, and build a world where people live in harmony with nature. Text available under Creative Commons licence. Thank you for your enquiry. Our team will be in touch soon Here are other ways to help WWF.
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