Antarctic life and ecosystems
Antarctica – a land of extremes
Antarctica is the highest, whitest, driest, coldest and windiest continent on Earth. It’s so cold that creatures often retreat to the sea to warm up. Add 24 hours of darkness during the winter months, and it’s a wonder anything lives there. Yet, Antarctica has thriving ecosystems on land and in the water.
The food web in the Ross Sea
This diagram shows how the food web in the Ross Sea, Antarctica, works. The arrows represent the energy flow and go from prey species (these get eaten) to predators (the hunters).
Notes: Baleen whales use baleen plates in their mouths to sieve plankton, krill and small fish from the water. Toothed whales have teeth for capturing prey. Krill is the dominant zooplankton species in the Ross Sea.
Skua (flying birds), phalder, 123RF Ltd; Adélie penguin, rhallam/123RF Ltd; Seal, Isselee/123RF Ltd; Fishing trawler, K_Stuart/123RF Ltd; Krill, Uwe Kils, CC BY-SA 3.0; Humpback whale (Baleen whale), Charles J Sharp CC BY-SA 4.0; Sperm whale (Toothed whales), Gabriel Barathieu, CC BY-SA 2.0; Phytoplankton, Public domain; Silverfish, martin_glhf, CC BY-NC 4.0, sourced from iNaturalistNZ; Toothfish, NOAA, Public domain; Zooplankton, Public domain; Flying squid, Darren Stevens, CC BY 3.0; Bacteria, Ivo Sedláček, CC BY 4.0; Benthic invertebrates, NIWA, CC BY-NC-ND 4.0; Ocellated icefish (Fish), Public domain.
Based on an original diagram by M. Pinkerton for NIWA.
Download a PDF version here.
An ecosystem is an interacting system made up of animals, plants, microorganisms and the physical and chemical environment they live in. Antarctica has marine ecosystems and terrestrial (land-based) ecosystems. Ecosystems rely on food webs – where energy and nutrients are passed from one living thing to another.
New Zealand ecosystem research
Two of the three research themes supported by Antarctica New Zealand involve protection, conservation and management of Antarctic ecosystems. Scientists study large marine creatures like Adélie penguins and Weddell seals, but they are also interested in really small benthic marine organisms.
Knowledge of megafauna like seals is crucial for understanding the ecosystem for its own sake and for understanding climate change. The top predators are like the gauge on the petrol tank.
Scientists also research what lives on the land. Antarctica is a polar desert. Terrestrial life is limited to the very small. There are no trees or shrubs, so vegetation is mainly mosses, lichens and algae. Springtails are one of the largest living terrestrial organisms – however, these invertebrates are only 1–3 mm in length! Mites and microscopic organisms like nematodes and bacteria live in the soil.
Adaptations for life in the freezer
Animals and plants that live in Antarctica have special adaptations that allow them to survive in the extreme conditions.
Nigel and Adélie penguins
Nigel visits an Adélie penguin colony at Cape Bird. He learns about their habits and adaptations with scientist Dr Amy Whitehead.
Penguins have thick, windproof and waterproof feathers. Penguins, whales and seals have thick layers of fat called blubber. Blubber acts as an insulator, helping to keep the animals warm. Antarctic animals often have small extremities (flippers and feet) to reduce heat loss.
Nature of science
Dr Amy Whitehead counts Adélie penguins – continuing research that began in the 1980s. Scientific knowledge is developed by a process of on-going inquiry, sometimes over months, years, decades or even centuries.
Plants are small and close to the ground to help protect them from fierce winds and dehydration. Algae can live in spaces between sandstone rocks where moisture and light are available. Lichens can carry out photosynthesis at very, very low temperatures and can survive dry periods by becoming dormant. Some invertebrates intentionally dehydrate to avoid damage caused by freezing.
Humans, ecosystems and adaptations
People living in Antarctica become part of the ecosystem. In the past, we weren’t too worried by this. Adventurers took pack animals to carry goods. Rubbish, huts and fuel spills were left behind when boats arrived to take explorers off the continent and back home. It’s very different today. People living in Antarctica do their best to minimise their impact on the environment.
Nigel Latta walks along the tracks made by others while he crosses the Dry Valleys and carries a special bottle to store his urine to ensure he leaves nothing behind.
One way Nigel and those living at Scott Base cannot avoid changing the landscape is with the buildings and transportation. Unlike the native plants and animals, humans have precious few adaptations for extreme weather living and travel! As an introduced species, we depend on well insulated clothing, buildings and vehicles to survive and navigate the icy continent.
Watch https://adam.antarcticanz.govt.nz/nodes/view/44058
Adélie penguins (video timecode 16:00–25:19)
Dry Valleys terrestrial ecosystems (video timecode 25:30–31:00)
Watch https://adam.antarcticanz.govt.nz/nodes/view/44059
Adélie penguins (video timecode 16:30–21:10)
Weddell seals (video timecode 2:25–9:00)
Dry Valleys terrestrial ecosystems (video timecode 24:45–30:40)
Antarctic life
Get up close with some of the Antarctic natives – from the very big (minke whales) to the very small (springtails and microalgae). Use these Science Learning Hub resources to read about the animal, plant and microscopic life in Antarctica.
Tardigrades and bdelloid rotifers use anhydrobiosis to survive in Antarctica’s extreme environments.
Activity ideas
Nigel sits in a small building (called a room with a view) and muses on Adélie penguin adaptations. These activities also get students musing about adaptations for life in the freezer. Both activities include a literacy component in which students use reading skills to locate and integrate information.
Animal and plant adaptations has students design a unique animal or plant capable of living in Antarctic conditions.
In Hiding in plain sight students investigate fish camouflage adaptations.
The education research article Reading aloud text with secondary students relates how one teacher used these Hub activities to help students with both their reading and their understanding of adaptation.
Deschampsia antarctica
Deschampsia antarctica is one of the grass species found on Antarctica’s peninsula. There are far more plant species on the Antarctic peninsula than the mainland, with the larger number of species at the peninsula’s northern end.
Antarctic ecosystems
Nigel visits the Dry Valleys and penguin and seal colonies and chats with Kiwi scientists who study these unique ecosystems. Learn more about ecosystems with these resources:
The article Changing times in Antarctica and the related podcast look at some of the possible impacts of a changing sea ice cycle on Antarctic ecosystems and the global climate.
The bottom of the food chain
NIWA scientist David Bowden explains the importance of the benthic food web and where phytoplankton is being eaten in the water column of the Ross Sea. NIWA scientist Julie Hall talks about the bottom of the food chain in the Antarctic waters, the bacteria, phytoplankton and zooplankton.
The top predators
NIWA scientist Stu Hanchet explains what types of top predators can be found in the Ross Sea.
Related content
The teacher resource Antarctica – literacy learning links lists selected articles from the Connected and School Journal reading series that support the science concepts when teaching about Antarctica.
Antarctic microscopic organisms
In Antarctic life – microalgae, meet a team of researchers investigating the phytoplankton that live on the bottom of the ice and among the sloshy platelet ice layer just below it.
In the Connected article Catch my drift, students learn about phytoplankton – tiny floating organisms that form the base of the marine food web. The article looks at two types of phytoplankton – dinoflagellates and diatoms.
Activity idea
The activity Making a food web enables students to describe relationships between organisms within the Antarctic ecosystem and build their own food web to show the interdependence of organisms in an ecosystem.
Citizen science projects
These citizen science projects ask for help to analyse images of Antarctic life:
Penguin Watch – Zooniverse – help scientists establish valuable baseline data about the numbers, locations, habits and health of penguins in a range of Southern Ocean sites.
These two projects have now finished, but they have links to general information and the results:
Crabeater Seals – Tomnod – looked at Crabeater seals living in the Southern Ocean surrounding Antarctica
Weddell Seals – Zooniverse – analysed images for information about changes in seal population numbers.
Adrift – nearly invisible to the naked eye, marine microbes drift continually in our ocean systems
Useful links
Find out more about food webs in our Food webs Pinterest board.
Find out more about the McMurdo Dry Valleys.
Discover more about Adélie penguins and Weddell seals on the Australian Antarctic Division website.
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