After James Ross Island and the Polar Plunge, we motored north towards our last destination in Antarctica, the South Shetland Islands. I spent every waking moment on the deck hoping for a fly-by Snow Petrel or Antarctic Petrel, but it wasn't meant to be.
Humpback Whale
I said my goodbyes to the amazing ice bergs.
Unfortunately most of the way north to the South Shetlands was spent overnight. Who knows how many Snow Petrels we went by in the dark.
The next morning we made it to Livingston Island and specifically Hannah Point for a shore excursion to another penguin and seal colony.
This is where we got our first looks at Elephant Seals! Massive creatures that have difficulty hefting their weight around on land. In the water they apparently one of the most accomplished deep divers and can do amazing things. Here is some text from Elephantseal.org which is more about the Northern Elephant Seal but the same applies.
"When diving to hunt, the northern elephant seal first exhales, emptying its lungs of almost all air. This reduces buoyancy and protects the seal from the bends (decompression sickness). All of the oxygen used to provide the energy needed during the remainder of the dive is stored in the red blood cells and the muscles. At the beginning of the dive the seal swims with its tail fins, however during the rest of the descent, almost 90% of the time the seal simply glides.
To enable the long period without breathing and the rapid recharge at the surface, the northern elephant seal has a very different surface and underwater metabolism. At the surface the seals have a heart rate of between 80 and 110 beats per minute. When diving, the heart rate drops typically to one-third the surface rate and occasionally as low as 3 beats per minute. Circulation becomes limited almost completely to the heart and the brain so that oxygen consumption is minimized.
Dive profiles are approximately V-shaped with vertical speeds of 2 to 5 mph (4 to 8 kph). A seal will swim approximately 15,000 to 20,000 miles (25,000 to 32,000 km) each year. They are capable of swimming at speeds up to 10 mph (16 kph) but usually travel more slowly to conserve energy.
When away from the continental shelf, seals dive somewhat deeper during daylight hours than at night. This probably reflects the behavior of the prey, approaching the surface at night, rather than the effects of reduced light on the seals.
Elephant seals have a very large volume of blood, allowing them to hold a large amount of oxygen for use when diving. They have large sinuses in their abdominal veins to hold blood and can also store oxygen in their muscles with increased myoglobin concentrations in muscle. In addition, they have a larger proportion of oxygen-carrying red blood cells. These adaptations allow elephant seals to dive to such depths and remain underwater for up to two hours.
The dive response slows down the seal’s heartbeat (bradycardia) and diverts blood flow from the external areas of the body to important core organs. Seals also slow down their metabolism while performing deep dives.
There were still some Antarctic Fur Seals about too. They are much more agile on land.
This Elephant Seal looked like it was about to sneeze....
The mighty bellow of an Elephant Seal is enough to knock a man over.
Gentoo Penguin
Chinstrap Penguin
Some people call them Stonecracker Penguins because of their loud calls.
Northern Giant Petrel giving me the stink eye as if to say "any closer and I am going to projectile vomit on you."
Check out that tube nose!
Juvenile Kelp Gull standing on the only greenery Antarctica has on land - moss and lichen.
Adult Kelp Gull
Elephant Seal - check out the little hail balls on the beach. We had a bit of a hail storm move in while we were on the island.
Earlier the naturalist crew had told us it was rare to see Leopard Seals on land. So we were really surprised to find this one...
The head of the Leopard Seal almost looks reptilian and friendly at the same time.
However, the Fur Seal did not like sharing the same beach and went on the attack causing the much bigger but much less agile Leopard Seal to shuffle back into the ocean.
A molting Chinstrap.
A Southern Giant Petrel with chick.
This crusty Elephant Seal escorted us to the shoreline and we said our goodbyes.
Although icebergs were pretty much gone, we did manage to find a glacier.
Fin Whale (I think! could be a Sei Whale)
There were a ton of whales on the way to our last destination, Deception Island.
Great times!
Last installment for Antarctica later this week.
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