In praise of gulls

I've talked quite a lot in these blogs about the large numbers of gulls that can be seen on the Scrape, especially as they come in to roost in late afternoon. While many people barely give gulls a second glance, except to moan at how noisy they are, these large gatherings are the perfect opportunity to compare the features and brush up on your identification skills.

There are six "common" species of gull in the UK. Of these, kittiwakes are mainly marine, only visiting land to breed. At Minsmere they visit the Scrape in spring to gather nesting material for their nests at Sizewell, and may be seen offshore in winter, but we'll exclude them from the mix when discussing our gull roost.

Two of the remaining species are "small" gulls: black-headed and common. The former nests in good numbers at Minsmere, but tends to be present only in small flocks in winter when they lose their chocolate brown hoods. Size, combined with a small dark red bill, red legs, and black ear-spot, should make identification quite easy. Common gulls are marginally bigger, with slightly darker back, mantle and wings, and larger white "mirrors" in the black wingtips. They have greenish legs and a dainty yellow bill. Despite its name, it's often the least common of the five "common" species at Minsmere.

The remaining three "common" species are all large gulls: herring, lesser black-backed and great black-backed. Herring gulls are the most numerous, and most familiar, as they are the big gulls most likely to be stealing your fish and chips at the beach. They have pale grey backs, pink legs, a heavy bill, and an aggressive expression. Lesser black-backed gulls are a similar size, with darker backs and yellow legs. Great black-backed gulls are the real monsters. They are huge, with black back and wings and pale pink legs.

Unfortunately, it's not as simple as that though. So far I have only talked about adult plumages, but of course every flock also has young birds, and to complicate things further the big gulls take four years to acquire full adult plumage. Therefore, many of the birds in the flock will not fit the descriptions above, but will have varying degrees of brown in their plumage. Identifying and aging these immature birds takes time and experience, with structural features such as shape, bill length and relative size being as important as plumage.

To make things more complicated, there are various other species to consider too. A few years ago two new species were "created", having previously been considered races, or subspecies, of herring gull. So we now have both yellow-legged and Caspian gull to throw into the mix. Both are increasingly frequent visitors to the UK, the former from the Mediterranean, the latter from eastern Europe. At first glance, both would be easily over looked as herring gulls, but there are some subtle differences. Adult yellow-legged gulls, for example have bright yellow legs, and their back and wing colour is somewhat intermediate between herring and lesser black-back, while Caspian gulls are slightly paler with longer pale pink legs and a softer facial expression. In early winter, both tend to have whiter heads too (herring gulls have variably streaked, "dirty-looking" heads at this time of year).

A yellow-legged gull by Jon Evans

I certainly don't claim to be an expert on the intricacies of gull identification, and particularly struggle to identify yellow-legged and Caspian gulls in anything other than adult plumage, so I was very pleased at lunchtime today to pick out two adult yellow-legged and an adult Caspian gull among the gulls on East Scrape. Normally I rely on the help of the gull experts among our guides and regular visitors.

I did have a good reason for checking the gulls carefully today though, as an Iceland gull had been reported earlier in the day (though I couldn't find it). Iceland gulls are easier to pick out than yellow-legged or Caspian gulls, providing you can see their wingtips. Iceland gulls, along with the bigger, bulkier glaucous gull, are often referred to as white-winged gulls, because there is no black in the wingtips. They are scarce winter visitors to Suffolk, but we usually spot both species at some point during the winter.

An immature Iceland gull (Photo via Google Images)

Another white-winged gull that you may spot at Minsmere is the Mediterranean gull, though only the adults have pure white wingtips. In breeding plumage they are very distinctive, with full black hoods and bright red bills, but in winter they can be harder to spot. There was one on the Scrape this morning, but spring is the best time to see them at Minsmere. 

The tiny little gull is a regular visitor to the Scrape in summer, but more likely to be spotted offshore in winter. Other gulls species can occur too, though any sighting will attract a lot of interest due to the extreme rarity in the UK. Examples could include laughing, Franklin's, Sabine's or Bonaparte's gulls from North America or Audouin's and slender-billed gulls from the Mediterranean, but I won't complicate things by outlining their ID features.

Why not allow yourself a bit more time than usual scanning through the gulls on the Scrape on your next visit (or in a roost at your local gravel pits or reservoir). But please be aware that there will be essential habitat management work on East Scrape for the rest of this week (it will be finished by the weekend), so the gulls may move to South Scrape or the South Levels for a few days.

Of course, it's not just gulls on the Scrape, with large flocks of wigeons, gadwalls, teals, shovelers and mallards, several shelducks, and a handful of pintails as well as lapwings, curlews and black-tailed godwits all present. Not forgetting a regular visit from a peregrine or two.