Heermann's Gull vs Greater Crested Tern
Larus heermanni compared with Thalasseus bergii
Side-by-Side Comparison
| Attribute | Heermann's Gull | Greater Crested Tern |
|---|---|---|
| Scientific Name | Larus heermanni | Thalasseus bergii |
| Order | Charadriiformes | Charadriiformes |
| Family | Laridae | Laridae |
| Conservation Status | Near Threatened | Least Concern |
| Length | — | — |
| Wingspan | 67.2 cm (26.5 in) | 71.6 cm (28.2 in) |
| Weight | 448.26666666666665 g (15.81 oz) | 367.75 g (12.97 oz) |
| Diet | -- | -- |
| Clutch Size | 1-2 | 1-3 |
| Population Trend | — | — |
Habitat Comparison
Conservation Status
Near Threatened
Heermann's Gull
Least Concern
Greater Crested Tern
About These Birds
Heermann's Gull
Heermann's Gull, 46–51 cm, is distinctive — dark grey body, white head (breeding), red bill. Breeds almost entirely on Isla Rasa in the Gulf of California, then disperses north along the Pacific coast to British Columbia. Kleptoparasite; steals fish from Brown Pelicans. Near Threatened; range highly restricted.
Greater Crested Tern
Greater Crested Tern, 43–48 cm, is the largest crested tern of the Indo-Pacific, breeding from South Africa to Japan and Australia. Yellow-green bill, prominent black crest, grey back. Colonial breeder on sand islands; plunge-dives for fish. Partially migratory; disperses across Indian and Pacific Oceans.