Birds of Ireland: Black-headed gull

A black-headed gull has a noisy, high-pitched call which includes a thin-sounding, drawn-out kaaww — and they also engage in softer 'chatter'

A black-headed gull lands on a lake in Dublin. Picture: Cathal McNaughton / PA

Black-headed gull [Faoileán an chaipín | Chroicocephalus ridibundus]

A black-headed gull is about 38-44cm long, with a wingspan of 94-105cm.

They are a common breeding species found here all year around — every from at sea/on the coast to estuaries, wetland and farmland. 

Jackdaw-sized, an adult black-headed gull's breeding plumage features a dark chocolate-brown head; white underside; pale grey back/wings, and dark red beak/legs.

Adult in non-breeding plumage have a dark spot behind eye; two dark smudge-lines on head; legs/base of beak paler.

Black-headed gulls in their first year have dark brown/black on wings; thin black tail band; orange-yellow legs; pale brown-yellow beak/black tip. In flight, you may see an adult black-headed gull's pale grey back/wings; with their white leading edge to outer primaries forming white triangle (above and below) with black trailing edge.  And when flying the reduced white on outer primaries; dark trailing edge to secondaries; brown wing coverts; black tail band of a bird in its first year may be visible.

Black-headed gull

A black-headed gull has a noisy, high-pitched call; includes thin-sounding, drawn-out kaaww; they also engage in softer 'chatter'. 

Tip of the Week: 

The timing of a bird's moult can be different for males and females.

Most Irish male duck species, for example, the mallard, moult in June and do it so fast that it is flightless for up to four weeks, while the females moult and becomes flightless only after the young are independent, typically in July or August. For the mute swan, it is the exact opposite: the female becomes flightless two or three weeks after the cygnets have hatched while the male starts moulting only when the female regains her full power of flight. Some of our migratory birds moult completely before leaving Ireland; others have a partial moult here, pause it during migration and finish the process on arrival at their summer or wintering grounds, while a few will wait until the migration flight is over.

Trauma and shock can cause a bird to lose some of its feathers, which are usually replaced straight away, and disease and starvation can cause a bird to suspend its moult until it recovers or finds a food supply.

All these moult-related plumage changes can result in the same bird species looking different at different times of the year and at different ages before adulthood.

Don’t worry if you find moult complicated and confusing.

As you watch the birds around you more and more, you will notice patterns emerging, such as black-headed gulls losing their dark hood in winter and black-tailed Godwits gaining their rusty breeding plumage in spring. You will eventually get to know the moulting patterns of different species which will help you identify some birds and get a greater understanding of the lives of others.

Featured in Birds of Ireland: A field guide by Jim Wilson with photographs by Mark Carmody

• Jim Wilson is a wildlife writer, broadcaster, tour leader, and former chairman of BirdWatch Ireland. He has been involved in the study and conservation of birds in Ireland for more than 45 years, contributing to several major surveys and international projects.
• Mark Carmody is an award-winning wildlife photographer, has a PhD in biochemistry and works as a European patent attorney.