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, fungi, 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
The Antarctic Science Platform, a major New Zealand Government-funded project, has three key areas of research. Two areas focus on land and sea ice, and the third looks at the vulnerability of Ross Sea Region ecosystems to environmental change. The Platform’s portfolio includes long-term and short-term projects. Examples of long-term projects include the Adélie Penguin Census (1981) and Ross Sea Toothfish (2012).
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.
Adélie penguin and chick
Adélie penguins have a compact body shape. This minimises their surface area and reduces heat loss. Adélie penguins build their nests out of stones – choosing a sloping site that allows snow melt water to drain away.
Adaptations for life in the freezer
Animals, plants and fungi that live in Antarctica have special adaptations that allow them to survive in the extreme conditions.
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.
Some invertebrates – for example, tardigrades and rotifers – intentionally dehydrate to avoid damage caused by freezing. Extremophilic microorganisms living in Antarctica’s geothermal regions are polyextremophiles, which means they have adaptations to survive severe cold, heat, desiccation and/or intense UV radiation!
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.
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.
Gearing up in Antarctica
Watch what it takes to gear up for outdoor work in Antarctica. There’s even a pocket count to help you remember where you put your phone!
Select here to view questions for discussion, a point of interest and copyright information.
One way people 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.
Antarctic life
Get up close with some of the Antarctic natives – from the very big (minke whales) to the very small (springtails and microalgae).
Antarctic ecosystems
Learn more about ecosystems in Antarctica 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.
Activity ideas
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.
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.
Citizen science projects
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 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.
Visit Antarctica New Zealand’s website to find out more about:
New Zealand’s Antarctic Science Platform
Current science programmes happening in Antarctica
long-term science programmes happening in Antarctica
