Black-legged kittiwake Rissa tridactyla

Identification Tips:

• Sexes similar
• Medium-sized gull
• Bill relatively slim with indistinct gonydeal angle
• Black legs

Adult alternate:

• Bright yellow unmarked bill
• Dark eye
• White head, neck, breast, and belly
• Gray back and upperwings
• Thin white tertial crescent
• Primary tips black with no white spots
• White tail

Adult basic:

• Like adult alternate but dark smudges on nape

Juvenile/First-year:

• Black bill
• Black ear spot
• Black collar
• White head, tail, and underparts
• Gray back
• Black outer primaries and carpal bar contrasting with paler inner primaries and secondaries
• Black terminal tail band

Similar species:

Only the Red-legged Kittiwake shares the solid black wingtips and plain yellow bill of the adult Black-legged Kittiwake. The adult Red-legged Kittiwake has a darker mantle, shorter bill, darker color underprimaries, and red legs. Immature Black-legged Kittiwakes have bold wing patterns that are similar to immature Bonaparte's, Black-headed, and Little gulls but have a distinctive black collar. Immature Red-legged Kittiwakes lack a black tail band and dark carpal bar.