Journey to the Ross Sea #1

In February 2015, Rob Lott, WDC’s Policy Manager, will be heading to New Zealand to join a ship’s expedition to the Ross Sea in Antarctica. Over the coming weeks he will provide updates through blogs and images of this fragile ecosystem highlighting the region’s landscapes and wildlife while also documenting the environmental threats the Antarctic currently faces.

To kick off this series we will start with an overview of Antarctica’s wildlife and the Ross Sea – a region scientists refer to as The Last Ocean.

The Antarctic continent and the surrounding Southern Oceans are considered the largest marine mammal feeding grounds on the planet today. If you are lucky enough to travel to this region, you will be rewarded with an incredible whale and dolphin watching experience. A huge number of species make their homes here or come to these waters to feed.  You are most likely to encounter Antarctic minke whales, humpback whales and orcas. It’s estimated that there are around 25,000 orcas in Antarctic waters and the pioneering work of researchers such as Dr Bob Pitman and Dr John Durban into the different populations of Antarctic orcas has been particularly fascinating. It appears the issue is not black and white at all!

Like the fish-eating ‘resident’ orcas and the mammal-eating Bigg’s or ‘transient’ orcas of the Pacific Northwest, familiar to us through adopt a whale, some of the Antarctic orca populations live in the same areas but with no social interaction between the different groups. This suggests these may be different species.

These distinct populations are known by scientists as ‘ecotypes’ and we now know there are probably four different ecotypes of orcas around Antarctica and the sub-Antarctic islands. Each ecotype looks different, has different feeding habits and possibly even ‘speaks’ a different language. Type A looks most familiar to us looking much like the Canadian orcas we know from WDC’s adopt an orca programme. Type B has two forms, large and small, and their skin has a yellowish hue. Type C orcas live deep in the pack ice and often miles from open water. And a fourth group, Type D, has only recently been recognised. These whales have a very small wispy eye patch and a bulbous head.

The rich culture and distinct behaviour of these different groups of orcas with their unique dialects, cooperative feeding strategies and transmission of knowledge through the generations is matched only by their equivalent terrestrial top predator – humans.

Type C orcas have only been seen in the Ross Sea region on the eastern side the Antarctic continent and have therefore become known as the Ross Sea orca. First discovered in 1842 by James Clark Ross, the Ross Sea is also known as the ‘last ocean’ because its ecosystem is structured on natural and not man-made forces. This makes it one of the last remaining stretches of ocean on Earth not to have been harmed by human activity. It is for this reason that Antarctic scientists believe there is a unique opportunity here to study a pristine ecosystem that is operating ‘fully functionally’.

Adventure cruise ship expeditions to the Ross Sea are rare with most Antarctic passengers visiting the more accessible Peninsula side of the continent. For the fortunate few, lucky enough to visit this vast wilderness, the rewards are huge. The freezer opens its doors for just a short period each year when the ice thaws enough to allow vessels access. This opens a window to a glittering world of sea and ice studded with massive icebergs, spectacular ice cliffs, incredible wildlife and the chance to follow in the footsteps of Scott and Amundsen and other adventurers from the heroic age of Antarctic Exploration.  

Sailing into the Ross Sea takes you further south into the Continent than any other sea route and as you cruise alongside the immense Ross Ice Shelf – the largest body of floating ice in the world – the South Pole lies just 800 miles away.

The wildlife is astounding along the Ross Sea with huge colonies of Adélie penguins as well as Emperor penguins and Antarctic petrels. What is especially interesting about this region though is that, unlike the rest of the world’s oceans, its top predators haven’t been exploited and its numbers of fish, seals, minke whales and orcas have been relatively high.

But the clock is ticking.

The slaughter of minke whales in Antarctica by Japanese whalers, under the guise of ‘scientific whaling’ has been well-documented, but today there is a new fishery in town. Large scale commercial fishing for toothfish, the main prey for Type C orcas, has recently been established in the Ross Sea. Toothfish are slow growing, reach up to 6ft in length and weigh over 200lb. The fishing boats target the larger specimens – the older fish that are most actively reproducing – and this can lead to dramatic population decreases in a very short time. If the planned expansion of the toothfish fishing industry continues, their population may be reduced by as much as 50% of its current size in the next 35 years. As the orca’s prey is fished in such huge numbers by humans, scientists are already beginning to notice a decrease in Type C orcas near McMurdo Sound.

WDC is campaigning hard to have the Ross Sea declared a marine reserve protecting up to 1.4 million square miles of this unique ecosystem. This may be one of the last places on Earth where sea ice remains year round. As a ‘living laboratory’ to study the Earth’s dynamic processes and ecosystems, the Ross Sea rates alongside such iconic places as the Galapagos and Hawaii. If fully protected, this marine reserve would be the jewel of all protected areas on the ‘last continent’ and stand as a shining beacon of what can be achieved through international treaties and conventions designed to conserve this astonishingly beautiful region…and the heart of Antarctica.