Birds are amazing creatures that are capable of migrating vast distances every year. There are many species of migratory birds that travel hundreds or even thousands of miles between their breeding and wintering grounds. But which bird travels the farthest? The answer is the Arctic tern, which migrates about 44,000 miles round-trip from pole to pole every year.
The Arctic tern breeds in the Arctic during the summer months. Once winter arrives, it flies an astonishing 22,000 miles to Antarctica for the summer season there. This round trip migration is the longest regular migration of any bird or animal on Earth. Keep reading to learn more facts about the epic journeys of the Arctic tern.
What Is Migration?
Migration refers to the seasonal movement of animals from one area to another in order to find more favorable conditions. Many birds migrate to take advantage of abundant food sources, suitable breeding habitat, and comfortable weather conditions.
There are a few different types of migration:
- Latitudinal migration – This north-south migration is what most people think of when it comes to bird migration. Birds fly from their breeding grounds in the north to warmer climates farther south for the winter.
- Longitudinal migration – This migration follows an east-west pattern instead of north-south.
- Altitudinal migration – Here, birds move up and down mountains to escape extreme winter weather.
- Irruptive migration – In this type of migration, birds temporarily move outside their normal range if food becomes scarce in a particular region.
The Arctic tern’s massive migration from pole to pole is an example of latitudinal migration. Next, let’s look at some key facts about the Arctic tern itself.
Key Facts About the Arctic Tern
Here are some quick facts about the record-holding migratory bird:
- Scientific name: Sterna paradisaea
- Wingspan: 20-24 inches
- Body length: 15 inches
- Weight: 2.8-5.3 oz
- Coloring: Gray and white plumage, red beak, red/black legs
- Diet: Small fish, shrimp, insects
- Habitat: Coasts, tundra, wetlands
- Population: 2-3 million pairs
- Conservation status: Least concern
The Arctic tern is a medium-sized seabird with slender, pointed wings. Its streamlined body shape makes it built for endurance flights. Next, we’ll look at the bird’s amazing migration route.
The Epic Migration Route
The Arctic tern migrates from Arctic to Antarctic and back again each year. This annual round trip covers about 44,000 miles!
Here is an overview of the Arctic tern’s migration:
- Breeds in Arctic regions circling the North Pole, including Northern Europe, Siberia, Alaska, and Northern Canada
- Migrates south in the autumn through western Europe and the coasts of Africa and South America
- Winters in the pack ice of Antarctica seas
- Travels north again in spring, back to the Arctic breeding grounds
The Arctic tern sees two summers per year thanks to this global migration. The map below traces out the bird’s epic journey.
Image source: U.S. Fish and Wildlife Service
As the map shows, the Arctic tern flies an astonishing round-trip of about 22,000 miles from pole to pole each year. No other migratory animal travels as far.
How Do Arctic Terns Fly So Far?
The Arctic tern’s immense migration is an incredible feat of endurance. Here are some key facts about how this bird is able to fly enormous distances:
- Aerodynamic body shape – The Arctic tern has long, narrow wings and a streamlined body perfect for efficient flight.
- Resting on ocean currents – Terns can rest on the sea surface and drift long distances with ocean currents to conserve energy.
- Fat stores – Before migrating, terns eat extra to build up fat reserves that power their journey.
- Short hops – Terns migrate in shorter hops with brief stopovers to rest and feed.
- Strong navigational skills – Terns use the sun for direction and have an internal magnetic compass and mental map of migration route.
Terns have many physiological and behavioral adaptations that enable their extreme endurance flights year after year.
Interesting Facts About Arctic Terns
Beyond their superlative migration, Arctic terns exhibit many fascinating behaviors and characteristics. Here are some interesting Arctic tern facts:
- Mate for life – Arctic terns breed in colonies and pair up with a lifelong mate. Partners work together to defend their nest and raise young.
- Extremely long-lived – Arctic terns can live over 30 years, the longest lifespan of any tern species.
- Aggressive breeders – Terns fiercely attack any predators or competing birds that enter their nesting territory.
- Plunge divers – To catch fish, terns dive from flight into the ocean at speeds up to 40 mph!
- Endangered by oil spills – Oil spills pose a major threat, damaging terns’ waterproof plumage.
- Travel farthest of any animal – At over 44,000 miles round-trip, the Arctic tern migrates the farthest of any known animal.
The tenacious, feisty nature of Arctic terns enables them to survive for decades and complete their record-breaking migrations year after year.
Threats Facing Arctic Terns
Despite their impressive resilience, Arctic terns face growing threats on their migration:
- Habitat loss at breeding sites
- Disturbance of nesting colonies from human activity
- Oil spills that coat their feathers
- Climate change affecting prey abundance
- Increased storms and extreme weather
- Pollution and plastics in marine feeding grounds
Protecting coastal ecosystems and minimizing offshore oil spills in the Arctic and Antarctic regions are key to preserving tern populations.
Efforts to Protect Arctic Terns
Some positive conservation steps have been taken to protect Arctic terns:
- Designated important nesting sites as protected areas
- Require buffer zones around tern colonies where no disruptive activities are allowed
- Band birds to track migrations and population trends
- Remove invasive predators from nesting islands
- Educate coastal communities about reducing disturbance
- Monitor contamination levels in eggs and adults
International cooperation is needed to sustain protections across the terns’ migratory range from the high Arctic all the way down to Antarctica.
Can Arctic Terns Keep Up with Climate Change?
The rapid pace of climate change poses new challenges for Arctic terns. Here are some of the impacts researchers are concerned about:
- Declining sea ice reducing nesting habitat
- Prey availability shifting with warming seas
- Increased storms battering breeding colonies
- Drying conditions at some nesting sites
Arctic terns exhibit flexibility in choosing nesting sites, which may enable them to adapt to some habitat shifts. But it remains to be seen whether terns can adjust quickly enough to keep pace with global warming.
Conservationists are tracking tern populations very closely to see how they respond to climate change in the coming decades. The terns’ incredibly long migration gives them exposure to environmental changes happening in both polar regions.
Significance of the Arctic Tern’s Migration
The superlative migration of the Arctic tern is astounding and has important ecological significance:
- Inspires wonder at the natural world and animal resilience
- Indicates health of Arctic and Antarctic ecosystems
- Connects distant continents and diverse habitats
- Spreads resources between northern and southern regions
- Provides important data on global climate trends
The Arctic tern embarks on an odyssey each year that connects critical habitats around the world. Studying these marvellous migrants provides insights into ocean health, global weather patterns and the extreme feats that animals can achieve.
Conclusion
The Arctic tern’s epic migratory journey from pole to pole makes it the reigning champion of marathon migrations in the animal kingdom. This incredible voyage is fueled by the tern’s aerodynamic design, navigational skills, endurance and flexibility to find resources across the earth’s oceans. While climate change poses new threats, the resilient Arctic tern continues its extraordinary global odyssey each year, offering inspiration and insights about the natural forces shaping our world. Learning more about these far-flying birds highlights the interconnectedness of ecosystems from the Arctic to Antarctic.