Gull Migration
I happen to live near a great sea-watching spot on the South Coast, where on good days in March flocks of the gorgeous Mediterranean Gull stream by. The beginnings of Little Gull migration are also apparent during the month. Other more common gulls may be noted migrating, including Common and Black-headed. Last year on spring migration, an Iceland Gull was tracked along the Sussex coast. And with our fantastic year of white-wingers I believe that by the end of the month there will be a smaller, secondary peak in the north of the UK, as Glaucous, Iceland and Kumlien's Gulls from further south return north to their breeding grounds.
Sea-watching can be a great opportunity to watch gull migration in action. Mediterranean Gulls are mainly a southern speciality (they occur further north but in nothing like the same numbers) but in the south it's definitely worth looking out for a few among flocks of Black-headed Gulls on reservoirs, landfills and anywhere else a migrating gull would be tempted to stop and feed. The same applies for Little Gulls, though their numbers are greater later in the spring in my experience.
(Mediterranean Gull- © John Bridges) |
Gull Moult
By the end of the month adult Black-headed, Little and Mediterranean Gulls will mostly have acquired their full hoods, and adult Common Gull and large white-headed gull species (LWHG) will mostly have lost their winter streaking. The moult of all the juvenile ages of gulls is too bewildering for me to detail fully in this post alone, but for a example lets take Herring Gull;
first winter into second-winter: generally from April-Oct, head first, body second, then mantle, scapulars, coverts and finally primaries
second-winter to second-summer; partially takes place from January to April, including head, most body feathers and scapulars. Coverts begin to moult from mid-may
second into third-winter; generally from April-Oct, as for first into second winter moult
info from 'Gulls of Europe, Asia and North America' by Klaus Malling Olsen and Hans Larsson
I included the two Apr-October moults as, last time I went 'gulling' I saw several first-winter Herring Gulls that had began the moult of their head-feathers, proving not every gull goes by the book and some can moult early. Ageing some gulls can be a challenge at this time of year (though a fun one if you're me!).
Gulls courting
At Rye Harbour, a well-known colony of Mediterranean and Black-headed Gulls, the birds are already starting to arrive, and by the end of March nest-building will be complete (per Barry Yates, warden of Rye Harbour, posting on the Sussex Ornithological Website).
If you live up North, the gulls in your seabird colony are probably the most boring creatures there. But aside from Fulmars, Rock Pipits and the odd pair of Peregrine and Raven, the seabird colonies in SE England consist almost entirely of gulls. Black-legged Kittiwakes have one of their most southerly colonies at Splash Point, right on my doorstep, and it's always great to see them arriving and beginning their courtship, mainly from March onwards.
And finally, though they're almost universally hated, the Herring and Lesser Black-backed Gulls that seemingly nest in almost every city in the country are a seabird colony on a lot of people's doorsteps!
Target Gull Species
MEDITERRANEAN GULL- arrives on breeding grounds, and migrants often appear in good numbers in some areas. The only gulls regularly occurring resident gull species with white primaries, and it's dark black hood, plaintive expression and Eider-like-voice make it a particularly endearing species.
ICELAND GULL- expect a return migration with birds once again concentrated in Northern areas, before their final push towards Greenland.
KUMLIEN'S GULL- the same applies, though they'll be heading for Baffin Island. This is perhaps a chance to connect with one if you haven't already (like me!)
GLAUCOUS GULL- the same as the two above, though they haven't been as numerous as Iceland Gulls this winter
LITTLE GULL-by the end of the month migration of this attractive little species should be beginning, with some in summer plumage. Based on my experience, often seen from sea-watching sites or reservoirs, but can turn up almost anywhere
(Kittiwake-© John Bridges) |
also, keep an eye out for some ridiculous vagrant. warm Southerly winds and high pressure might waft an Audouin's or Slender-billed Gull up if we're really lucky!
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