Common Tern vs Arctic Tern for Kids
Common Terns and Arctic Terns are close relatives that can look almost identical over bright water. Both have pale gray backs, black caps, forked tails and red legs in breeding season. The Common Tern, Sterna hirundo, is usually a little heavier, has longer legs and often shows a black tip on its orange-red bill. The Arctic Tern, Sterna paradisaea, has very short legs, longer tail streamers and usually a completely red adult bill. Its yearly migration links the Arctic and Antarctic.
Common Tern
- Type: Living
- Group: Tern species in the gull family Laridae (Sterna hirundo)
- Known for: Black cap, orange-red bill with a black tip, red legs, graceful hovering and plunge-diving for fish
- Diet: Carnivore; mainly small fish, plus crustaceans and aquatic insects
- Special skill: Hovers to aim, then plunges into shallow water and lifts out with a small fish in its bill
Arctic Tern
- Type: Living
- Group: Tern species in the gull family Laridae (Sterna paradisaea)
- Known for: Very long tail streamers, short red legs, mostly all-red adult bill and the longest regular migration of any animal
- Diet: Carnivore; mainly small fish and marine crustaceans
- Special skill: Tracks productive winds and feeding zones on a pole-to-pole journey between northern and southern summers
Quick Answer
Look at several clues together. A breeding Common Tern usually has an orange-red bill with a black tip, longer red legs, a slightly larger head and shorter tail streamers. A breeding Arctic Tern usually has an all-red bill, very short legs, paler-looking wings and tail streamers that extend beyond the folded wing. Young and nonbreeding birds are harder to separate.
Common Tern vs Arctic Tern: Quick Comparison
| Feature | Common Tern | Arctic Tern |
|---|---|---|
| Scientific name | Sterna hirundo | Sterna paradisaea |
| Average British mass | About 127.5 g in BTO records | About 103.8 g in BTO records |
| Breeding bill | Orange-red, usually with a black tip | Usually shorter and entirely deep red |
| Legs | Red and noticeably longer | Red and very short |
| Tail | Forked with moderate streamers | Deeper fork with longer streamers |
| Folded-wing clue | Tail usually does not project far beyond wing tips | Tail streamers often project beyond wing tips |
| Flight impression | Graceful, with a slightly heavier head and body | Especially light, buoyant and delicate |
| British nesting habitat | Coastal and inland waters | Almost entirely northern coasts and islands |
| Typical clutch | Usually 2-3 eggs | Usually 1-2 eggs |
| Migration | Mostly winters along western and southern coasts, including Africa | Migrates between high northern breeding grounds and Antarctic waters |
How Are Common and Arctic Terns Alike?
- Both are slender white-and-gray seabirds with black breeding caps and deeply forked tails.
- Both hover over water and plunge down to catch small fish near the surface.
- Both are long-winged migrants that spend much of the year around coasts and open water.
- Both nest on the ground in colonies and defend eggs or chicks with noisy swoops.
- Both carry fish crosswise in the bill when feeding a mate or chick.
How Are Common and Arctic Terns Different?
- A Common Tern is usually a little heavier and longer-legged than an Arctic Tern.
- The Common Tern’s breeding bill often has a black tip; the Arctic Tern’s is usually all red.
- Arctic Tern tail streamers are longer and commonly extend beyond the folded wings.
- Common Terns regularly use inland lakes and reservoirs, while British Arctic Terns breed only on coasts.
- Arctic Terns migrate much farther, traveling between northern breeding grounds and Antarctic waters.
Common vs Arctic Tern Adaptation Showdown
- Size – Common Tern: The species overlap in length, but BTO’s British records give the Common Tern the greater average mass.
- Speed – Tie: Both are swift aerial hunters, and different wind, route and flight styles prevent a fair single speed champion.
- Strength – Common Tern: Its slightly heavier average build gives it more total body power; this is not a fight prediction.
- Stealth – Arctic Tern: Its paler, more translucent-looking wings can merge beautifully with bright northern sky and sea.
- Social – Tie: Both form noisy nesting colonies and cooperate informally when driving threats away.
- Swimming – Tie: Both float and bathe, but they hunt mainly by plunge-diving rather than sustained underwater swimming.
- Weirdest – Arctic Tern: Its route lets it experience northern summer and southern summer in one year, producing extraordinary lifetime air miles.
Fun Common Tern vs Arctic Tern Facts
A Journey Between Summers
After breeding in the far north, Arctic Terns follow long ocean routes toward Antarctic waters, then return north the next year.
The Bill-Tip Puzzle
A breeding Common Tern usually shows a dark tip on its orange-red bill. An adult Arctic Tern’s shorter bill is usually red from base to tip.
Legs Like Landing Gear
Common Terns stand higher on longer legs. Arctic Terns have such short legs that a resting adult can look as if its belly nearly touches the ground.
A Tail Beyond the Wings
When an adult Arctic Tern folds its wings, the long tail streamers often stick beyond the wing tips. A Common Tern’s shorter streamers usually do not.
An Inland Tern
Common Terns can nest on islands and rafts in reservoirs, lakes and flooded gravel pits. In Britain, Arctic Tern colonies are coastal and mostly northern.
Common Tern vs Arctic Tern Quiz
Which tern usually has a black tip on its breeding bill? A) Common Tern B) Arctic Tern C) Both always Answer: A) Common Tern
Which tern has shorter legs? A) Common Tern B) Arctic Tern C) They are identical Answer: B) Arctic Tern
Which tern often nests beside inland water in Britain? A) Common Tern B) Arctic Tern C) Neither Answer: A) Common Tern
Which bird makes a pole-to-pole migration? A) Common Tern B) Arctic Tern C) Both follow the same route Answer: B) Arctic Tern
How do both terns commonly catch fish? A) By plunge-diving B) By digging burrows C) By climbing trees Answer: A) By plunge-diving
Common Tern vs Arctic Tern FAQ
Are Common and Arctic Terns the same size?
Their length ranges overlap, but Common Terns are usually a little heavier and look slightly more substantial.
Is bill color enough for identification?
No. Light, age and season change appearances, so check bill pattern, leg length, tail, wings, call and location together.
Do Arctic Terns really reach Antarctica?
Yes. Many travel from high northern breeding areas to productive waters near Antarctica and back each year.
Do both terns dive underwater?
They plunge into the surface for prey, but usually do not chase fish underwater for long like an auk or cormorant.
Why should nesting terns be watched from far away?
Ground nests are easily disturbed. Give colonies plenty of space and follow signs, ropes and local wildlife guidance.
Animal Words to Know
- Colony: A place where many birds of the same species nest close together.
- Migration: A regular seasonal journey between different regions.
- Plunge-dive: To drop from the air into water to catch prey.
- Streamer: A long, narrow outer tail feather.
- Translucent: Allowing some light to pass through, without being fully transparent.
Build a Tern Detective Strip
Build a Tern Detective Strip
Divide a paper strip into five clue boxes: bill tip, leg length, tail beyond wing, inland or coastal habitat, and migration. Draw both breeding adults from the side, then add the correct clue to each box. Finish with a reminder that one clue alone may not identify a distant tern.
Meet Each Animal
Want the full fact file? Here are quick highlights from each animal’s own facts page.
Common Tern Fact Highlight
From the full animal facts pageArctic Tern Fact Highlight
From the full animal facts pageMore Animal Comparisons
Pick another animal matchup and keep exploring. Tiny facts, big questions, very serious animal business.
Make an Animal Story
Create a tern story about an inland fish catcher meeting the world’s greatest long-distance traveler!