This article covers the most common gulls that you might see in the British Isles.
Did You Know? There are over 50 species of gulls worldwide. In the British Isles you might be lucky to see at least twelve of them!
Gulls are colloquially named seagulls, but in actuality, none of the species of gull in the world are called Seagulls, and lots of them can be spotted miles away from the sea. Gulls live for a long time, typically 20 years or so, and in particular the larger ones don’t start to breed until 4 or 5 years old. During this time almost all gulls go through various plumage transformations as they age, as well as seasonally when mature birds come into the breeding season.
Consequently, gulls can be notoriously difficult to identify and is the subject of many books. Birders will often talk about birds being in 1st winter plumage and second winter plumage etcetera. In this guide though, we will try to keep things as simple as possible to give you an introduction. This article covers the 6 gulls you are most likely to see in the British Isles, and will assist you identifying them.
European Herring Gull
Herring Gulls (Larus argentatus) are one of our larger gulls, with adults reaching up to 60 cm with a body weight of up to 1260 grams. So overall, they are quite heavy-set-looking birds. Generally speaking, you are likely to see gulls in groups, and often in mixed flocks, so size is always a good starting point to familiarize yourself with.
Some of the details to look out for on Herring Gulls are their pale grey backs and black wing tips with white spots. Look out for the flesh-colored pink legs, which are a good differentiator for this species compared to a Lesser Black Backed Gull which we are going to look at later. Herring Gulls also have yellow bills with a red spot towards the tip of the bill.
As mentioned, adults have different plumage in the summer and winter. In winter, they feature a mottled pattern on their heads.
As for juvenile birds, here is an idea of the plumage variation in a younger bird. You can see that the mottled pattern appears on their wing feathers, breast feathers, as well as their heads. The plumage also contains brown hues.
Common Gull
Our next species is the Common Gull (Larus canus). The name common is thought to be a reference to their habitat when the bird was first named. In that, they were often seen inland on land referred to as common grazing ground.
The Common Gull is superficially similar to the Herring Gull in appearance, but this is where an understanding of each species’ size comes into play. The Common Gull is significantly smaller than the Herring Gull, their body length is up to 42cm with a body weight of up to just under 500g.
Some key features to look out for are they have a more rounded head and a much finer bill than the Herring Gull. Additionally, the bill lacks the red spot seen on Herring Gulls. The eye is dark in color which somehow gives Common Gulls a less aggressive appearance. Further, note that the legs of the Common Gull are pale green-yellow, although it should be noted that Juveniles have pink-colored legs.
As with the Herring Gull, outside of the breeding season, the Common Gulls head takes on a mottled pattern.
In addition, juvenile Common Gulls have brown mottling on their wing feathers, breast, and head similar to that of the Herring Gull. So care is needed to consider the overall shape of the bird, its eye color, and its overall size to ensure a correct ID.
The Great Black-Backed Gull (Larus marinus) is the largest of all the gulls on the planet. By comparison, they make the Herring Gull look small!
They seem to love to push their weight around by bullying other birds. Their overall body length is up to 78cm and their body weight is up to 1.9 kg.
As their name suggests, their distinguishing feature is their almost black back and wing feathers. As with many gulls, the primary wing feathers have distinctive white spots. They are stocky-looking birds with powerful yellow bills used for ripping into their prey, and they share a red spot towards the tip of the bill similar to that of the Herring Gull. They also share the fleshy pink-colored feet of the Herring Gull. Overall though, you should try to differentiate the Great Black-Backed Gull based on its sheer size, distinctive black back, and powerful bill.
As with our previous gulls, winter plumage on the Great Black-Backed Gull includes mottled patterning. Further, Juveniles also have mottling on their wing and breast feathers.
One further consideration with this gull is habitat. They are rarely seen inland, spending their time along the coast, and from a UK standpoint they are most common along the west coast of Scotland.
Lesser Black-Backed Gull
The Lesser Black-Backed Gull (Larus fuscus) is somewhat of a smaller version of the Great Black-Backed Gull as they share many of the same features.
The first key differentiator to consider is the size of the bird. Lesser Black-Backed gulls are smaller with an overall body length of up to 64cm and a body weight of up to 1 kg. So overall they are about the same length as a Herring Gull but a little less bulky. The next thing to consider is their back and wing coloring. Their primary wing feathers are black, but their back and secondary wing feathers are more slate grey. During the breeding season, they also sport distinctive yellow legs.
As with the other gulls we have looked at in this episode, the adult Lesser Black-Backed Gull sports a dappled winter plumage on their head.
Juvenile Lesser Black-Backed Gulls are notoriously difficult to positively identify, as they look virtually identical to Juvenile Herring Gulls. Your best bet therefore is to consider other birds in the environment. Even this can be tough; especially if you are looking at large mixed flocks of gulls.
Black-Headed Gull
The next gull in our line-up is the Black-Headed Gull (Chroicocephalus ridibundus), which is the smallest of the breeding gull species to visit the British Isles.
Their body length is up to 37 cm with a body weight of just under 350 g. The name Black-Headed Gull is a bit of a misnomer as their heads are chocolate brown rather than black. It turns out however that the name Brown-Headed Gull was already taken and is the name of a gull resident in Asia. The Black-Headed Gull is relatively easy to identify with its delicate red bill and red legs.
However, care is needed outside of the breeding season as the adult birds lose their chocolate brown heads. They do though retain a dark mark just behind their eye. Another thing to look out for with these birds is they lack the white spots on their primary wing feathers that we have seen on the other gulls we have looked at so far.
Juvenile birds have the familiar mottled brown feather patterning.
Black-Legged Kittiwake
Our final gull is the Black-Legged Kittiwake (Riussa tridactyla). The Kittiwake is another small gull. Their overall body length is up to 40cm with a body weight of up to 434 g. Some key features of the Kittiwake to help identify them are.
They have a grey back and wings and white head and body. Their wing tips are black, and a key identification feature is that the black tips show both above and below the wings as though they have been dipped in ink. This is especially useful as an ID when you see the birds in flight. Similarly to the Black-Headed Gull, the Kittiwake doesn’t have the white spots on their primary wing feathers. Kittiwake bills are bright yellow, their eyes are dark, and their legs are long and black.
In winter, the Kittiwake head turns more of a dusky grey, and their bill turns more olive.
Juveniles are similar in appearance to non-breeding birds but have black coloring on the leading edge of their wings and the trailing edge of their tail feathers. They also have black bills as opposed to the yellow or olive of adults.
References
- Malling, Olsen, Klaus. Gulls of Europe, Asia and North America, Bloomsbury Publishing Plc, 2004. ProQuest Ebook Central. [Accessed 26/05/2027]
