The Hidden Wildlife of Antarctica
Dig a little deeper into the ecology of Antarctica and you’ll discover an intriguing realm of plants and animals, on which all life in the frozen continent depends.
Antarctica – a vast realm of snow-clad mountains, freezing waters and polar winds. In spite of its extreme environment, this icy desert is a haven for wildlife of all kinds, whether they have fins, feathers, or flippers.
Animals in Antarctica range from microscopic water bears called tardigrade to the world’s largest animal, the blue whale. The sizes of the other Antarctic inhabitants' range between these two extremes, and include penguins, seals, sea birds and a few land invertebrates.
But how can the coldest continent on Earth be home to such a large number of animals? The secret to understanding this lies in an unlikely place: under the lens of a microscope.
Getting your hands wet
During your exploration of Antarctica, we’ll use our small expedition boats to visit the coasts of the Antarctic Peninsula. As we do, we’ll have the opportunity to use a variety of oceanographic tools to examine the waters of the glacier-fed fjords here.
The simple Secchi disk, for example, measures water transparency while a CTD device looks at water conductivity, temperature, and depth. The Expedition Team will also use a specially adapted net to collect water samples directly from the sea here.
A whole new world of wildlife
The real discovery begins as you peer down the microscope back on board the ship in the Science Center. Thanks to the powerful magnification, what looked like just a standard drop of clear water is suddenly revealed to be a new dimension brimming with a myriad of microscopic organisms.
These tiny plants and creatures, collectively called plankton, exist as their own ecosystem, a hidden world of geometric and alien-like lifeforms not seen by the naked eye. While the many different types, shapes, and sizes are a marvel, they can be separated into two clear categories: phytoplankton and zooplankton. Together, they fuel a complex yet fascinating food chain that goes right up to seals, seabirds, and whales.
Phytoplankton are essentially tiny plants, living off sunshine in the shallow water and on nutrients brought to the surface by upwellings of deep ocean currents. In the Antarctic summer, 24 hours of sunlight boosts photosynthesis and causes the mini-solar factories to bloom in the water. Collectively, these microscopic plants are responsible for releasing over 50% of Earth’s oxygen.
This in turn creates an abundance of food for zooplankton – microscopic animals – to feast on. One such zooplankton is krill, a small, shrimp-like creature that can grow up to 6 cm in length. Swarms of krill are so dense that it is thought there may be as many as 30,000 in a single cubic metre of water.
Krill are an essential part of the menu for fish and squid, which then sustain populations of seals, penguins, and other birds, enabling terrestrial life to flourish on the shores of the frozen kingdom. Even the behemoth-level blue whale feeds primarily on krill, consuming as much as four tonnes of the miniscule microorganisms.
Everything counts in large amounts
All this means that almost all the animals living in Antarctica are able to tap the food chain close to the initial producers – the phytoplankton. Energy from the sun, converted by photosynthesis, is efficiently consumed rather than lost in any intermediate stages.
The fact that the largest animal on the planet is dependent on the smallest is a testament to the intricacies of nature. It is a powerful lesson in how we are all interconnected on this living planet. Indeed, without the humble phytoplankton as the starting building blocks, Antarctica’s amazing web of wildlife wouldn’t be possible. Every lifeform matters, even the tiniest.
Small changes have big consequences
With plankton forming such a crucial part of our oceans’ ecology, scientists are keen to monitor the overall health of these microorganisms. In light of such threats as climate change and microplastics, even small changes in plankton could have big consequences for us all.
For example, global warming leads to more glacial melt in Antarctica, diluting the salty sea water with freshwater. This then alters the living conditions for all life in the Southern Ocean, beginning with phytoplankton all the way up to whales.
Being part of the bigger picture
Scientists on your Expedition Team will talk enthusiastically and thoroughly about plankton and Antarctic wildlife during your expedition. You’ll also have the option of participating in Citizen Science initiatives that enlist the help of willing volunteers to check on plankton in different parts of the globe.
It’s as simple as connecting to a live scientific database to upload Secchi disk data or microscope photographs of plankton. Just doing this enables international research institutes to build current, accurate models which then help specialists better understand what’s happening in our world.
You’ll be able to count yourself among the wider scientific community, doing your bit to uncover important facts about our planet. Just as plankton is connected to all life in Antarctica, your contribution to Citizen Science will also make you part of something bigger. Is there a more worthy endeavour?