Seabird Identification

Start with the family

Place the bird in its group before worrying about the species. Albatrosses and petrels carry tube-shaped nostrils on top of the bill. Gannets and boobies have long, pointed wings, a dagger bill and a pointed tail. Auks look like small, compact footballs with whirring wings. Gulls and terns are the most familiar, but also some of the hardest to separate.

Shape, flight and behavior

Birders call the overall impression of a bird its "jizz". For seabirds this is often the most reliable clue. Shearwaters bank and glide low over the waves on stiff wings. Storm petrels flutter and patter at the surface. Terns hover and plunge. Skuas chase other birds to steal their food.

Plumage and age

Large gulls take several years to reach adult plumage, and each year looks different. Underwing patterns, the color of the bill and legs, and the pattern at the wingtip are the key details. Molt, wear and light conditions can change how a bird looks, so note several features, not one.

Tips for the field

• Note size against a bird you already know.
• Watch how it flies before reaching for the field guide.
• Photograph the bird in flight from above and below if you can.
• Record the date, location and sea conditions. Range and season narrow the options quickly.