Heermann's Gull vs Grey-backed Tern
Larus heermanni compared with Onychoprion lunatus
Side-by-Side Comparison
| Attribute | Heermann's Gull | Grey-backed Tern |
|---|---|---|
| Scientific Name | Larus heermanni | Onychoprion lunatus |
| Order | Charadriiformes | Charadriiformes |
| Family | Laridae | Laridae |
| Conservation Status | Near Threatened | Least Concern |
| Length | — | — |
| Wingspan | 67.2 cm (26.5 in) | 52.2 cm (20.6 in) |
| Weight | 448.26666666666665 g (15.81 oz) | 126.21666666666665 g (4.45 oz) |
| Diet | -- | -- |
| Clutch Size | 1-2 | 1 |
| Population Trend | — | — |
Habitat Comparison
Conservation Status
Near Threatened
Heermann's Gull
Least Concern
Grey-backed 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.
Grey-backed Tern
Grey-backed Tern, 35–37 cm, is a Pacific seabird breeding on islands from Hawaii to Micronesia and Polynesia. Pale grey back distinguishes it from the similar Bridled Tern; white below with black cap. Piscivore; surface-dips and shallow plunge-dives. Largely pelagic when not breeding.