Arctic Tern vs Secretary Bird
Sterna paradisaea compared with Sagittarius serpentarius
Side-by-Side Comparison
| Attribute | Arctic Tern | Secretary Bird |
|---|---|---|
| Scientific Name | Sterna paradisaea | Sagittarius serpentarius |
| Order | Charadriiformes | Accipitriformes |
| Family | Laridae | Sagittariidae |
| Conservation Status | Least Concern | Endangered |
| Length | 34.0 cm (13.4 in) | 130.0 cm (51.2 in) |
| Wingspan | 80.0 cm (31.5 in) | 210.0 cm (82.7 in) |
| Weight | 110.0 g (3.88 oz) | 3700.0 g (130.51 oz) |
| Diet | Small fish and crustaceans caught by plunge-diving from the air. Hovers briefly before diving. | Snakes, lizards, small mammals, and large insects. Hunts on foot, stomping prey to death with … |
| Clutch Size | 2-3 | 1-4 |
| Population Trend | — | — |
Size Comparison
Habitat Comparison
Arctic Tern
Breeds on coastal and tundra habitats. Spends most of its life at sea over the open ocean. Nests in colonies on beaches and rocky shores.
Secretary Bird
Open grasslands, savannas, and light woodland across sub-Saharan Africa. Avoids dense forests and very arid regions.
Song & Call Comparison
Arctic Tern
A sharp, grating 'kree-yah' alarm call. Also gives 'kik-kik-kik' near the nest. Highly aggressive vocally during the Arctic breeding season. Calls are harsh and insistent.
Secretary Bird
A surprisingly deep, resonant croaking 'kowrr-kowrr' often heard at dawn on African savannas. Also gives pig-like grunting sounds. Mostly silent compared to true songbirds.
Geographic Range & Migration
Arctic Tern
Breeds in the Arctic and sub-Arctic. Migrates to the Antarctic, experiencing two summers per year. Found on every ocean.
Secretary Bird
Sub-Saharan Africa from Senegal and Somalia south to South Africa. Resident throughout its range.
Conservation Status
Arctic Tern
Secretary Bird
How to Tell Them Apart
Arctic Tern
Pale grey upperparts, white underparts with a black cap. Blood-red bill and short red legs. Deeply forked tail streamers. Winter adults lose the full black cap.
Slender, pointed, bright red bill
Secretary Bird
Grey body plumage with black flight feathers and thigh feathers. Distinctive long black crest feathers trail from the back of the head. Orange-red bare facial skin.
Short, strong, hooked greyish bill with a yellowish cere
About These Birds
Arctic Tern
The Arctic tern holds the record for the longest known migration of any animal, traveling roughly 70,000 km annually from Arctic to Antarctic and back. Over its 30-year lifespan, it may fly the equivalent of three round trips to the Moon. This remarkable bird experiences more daylight than any other creature on Earth.
Secretary Bird
The secretary bird is the only raptor that hunts primarily on foot, striding through grasslands on crane-like legs up to 1.2 meters tall. Its name may derive from the crest feathers resembling quill pens tucked behind a secretary's ear. The species is classified as Endangered due to habitat loss and decline across much of its range.