In this second post on Antarctic Wildlife I’m focusing on the sea, mainly whales and seals.
There was a strong contingent of people on the voyage who went snorkelling or scuba diving. My impression is that they really didn’t see much in the way of biological organisms, large or small! From the zodiacs (read about them here), we could at times see quite deeply into the clear water. What did we see? Nothing! There was virtually no seaweed to be seen, and very little washed up on the shore, and certainly no fishes.
We did see chains of salps, and first thought these were plastics lost overboard from some boat! Rather, salps are gelatinous creatures with bright red internal organs. They reproduce asexually by forming long chains of individuals – which is what we were seeing. As salps are 90% water they don’t contribute significantly to the Antarctic food chain.
A chain of salps washed up on the shore
Whales
These always create the most excitement!
But I came away disappointed:, with one exception, my whales were long dead, or way off in the distance. Once I saw one within a couple of hundred metres, and then it flashed its tail at us and was gone: an Antarctic minke whale, perhaps. A couple of times when looking at a photo I’d taken of an iceberg or the scenery, I found a barnacled flipper or snout poking out of the water: a southern right whale, or a humpback whale, and over a kilometre away.
Minke whale, cruising by and going down
Others definitely fared better; you had to be in right place at the right time! Once, the Polar Pioneer slowed and stopped as the bridge had seen whales right next to the ship. An announcement was put over the p/a system, but by the time we were dressed for the outdoors and up on deck, they too were gone.
One of our landings, on the tiny island of D’Hainaut, was very poignant. It had the skeletal remains of a couple of whaling skiffs and masses of whale bones partially buried in silt and penguin poo.
Remains of whaling skiff and whales on D’Hainaut Island
The vertebrae, ribs and remains of skulls were simply enormous. Little wonder their living descendants cause such excitement.
Seals
And now, seals. Their dog-like faces and beautiful whiskers have an adorable appeal despite their somewhat rheumy eyes and great blundering bodies.
The first seals we encountered were Antarctic fur seals. These are the smallest of the seals, up to 1.5 m long, and closely related to dogs. They have teeth, fur rather than blubber, vestigial external ears, and can walk on all fours using their flippers as legs. Almost certainly the fur seals we encountered were females and pups. There was a lot of quarrelling amongst the pups: no doubt males practicing for being the boss of a harem.
Antarctic fur seals
On all-fours
Antarctic fur seals quarreling
Our fur seals may have been querulous, but they were also playful! We watched one group of youngsters frolicking in water enclosed by an iceberg reminiscent of a jumping castle. They also practiced seal yoga.
Come and play, it’s cold but absolutely delightful!
Seal yoga anyone?
These animals were hunted to the point of extinction – for their fur – and were regarded as commercially extinct by the early 1900’s. However, the population has recovered and now numbers in the millions. Ironically, fur seals have benefitted by the increase in the krill population due to 20th century Antarctic whaling.
The other seals were much larger than the fur seals, and seemed to be far more sedentary! They certainly cannot use their flippers to walk, but move by undulating the body. One Weddell seal was snoozing on the ice while we wandered around. It was easily 3 metres long and had a lovely almost cat-like face. This one did not move at all while we were watching it. Apparently Weddell seals are incredibly docile, and seem totally unaffected by human presence!
A Weddell seal
We also saw a lot of Crabeater seals, which are also quite large. They too seem to just lie around on ice flows. They don’t eats crabs! Rather, they eat krill and have specially adapted teeth to strain krill out of the sea water. Most of the Crabeaters we saw had parallel scars on their abdomen, being scars from Leopard seal attacks when they were pups.
Weddell seals on an ice flow near Verandsky Station – and the gorgeous green depths
Weddell seals
As for the Leopard seals themselves, I don’t think I saw one, and certainly don’t have a photo of one. They have a bit of a reputation for being vicious, so I’m not disappointed!
Krill
Finally, some comments about the Antarctic food chain.
Unlike elsewhere on the planet, it is an incredibly short step from the smallest creatures at the base of the chain, i.e. plankton, to the largest creatures on earth, the great whales. In between is a single organism: krill. In fact krill is essential to all Antarctic animals. Sure, the top predators, like leopard seals and killer whales, are carnivores and eat fish, penguins and seals, but these prey depend immediately on krill.
We did not see free-swimming krill by the coast; only sicked-up krill, and the remains of krill post-digestion by penguins or seals – i.e. as somebody’s poo. Krill are deep water creatures during the day, and only come to the surface at night – but never mind, whales, seals and penguins can dive quite deep!
Second hand krill?
The ultimate top predator, Homo sapiens, also has an appetite for krill. The thought that factory ships be given licence to harvest krill on a massive scale is a scary thought. This could potentially devastate the entire Antarctic food chain. Krill do not have the charisma or public appeal of whales, but krill are the corner stone of Antarctic wildlife, whales and all.
I sincerely hope krill harvesting is not going to be something that slips under the public radar!
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