Text Tarvo Valker, www.estbirding.ee
The first month of the ringfinder contest year is approaching its end by and by. In addition to looking for rings on excursions, and stories of finding rings we will also start introducing different ringing projects in a blog. To start with we will look more closely at gulls; talking of them suits the present season.
In winter gulls collect in larger numbers in harbours and near refuse deposits. Luckily in most fishing harbours it is possible on asking permission to get in and check the gulls by telescope. Although a few gulls with wing marks have been seen at times primarily gulls marked with coloured leg rings are mostly seen.
On seeing a colour marked gull be sure to take a photo of the bird if at all possible. In many cases it can provide useful extra information:
1. For following the plumage development of the birds. Since the precise age is often known of ringed birds then photos are always good illustration material
2. For more precise species identification. You may for instance read the ring of a herring gull that instead turns out to be a ringed Caspian gull. Likewise hybrids may at times be seen among gulls
3. For checking the reading of the rings. Certain letters and numbers may look incredibly similar in nature. Because of this it is always useful to have a photo of the ring.
Herring gull Hõbekajakas Larus argentatus
In the winter months this is the most numerous of our gull species, and the chances to read rings of this species in January-February are good. Now is the best time to visit harbours where fishing boats move (for instance Dirham, Veere). Searching for rings needs patience – best is to note rings when the birds rest on the harbour quay. Since herring gulls are early arrivals they can be found in quite large numbers on the sea ice already at the end of winter.
Herring gull marked in Sweden with red polymer ring (R:042), seen in Saaremaa, Veere harbour. Photo: Uku Paal.
Herring gulls marked with coloured rings as a rule come from our neighbouring countries. A large majority with rings read in Estonia are birds with Finnish colour rings. Our birdwatchers have managed to find much fewer herring gulls with Polish, Latvian and Swedish coloured rings.
Herring gulls with wing markers.can also be seen, but rarely. The birds above were observed in Pärnumaa, Liu harbour, in March 2009. /Photo: Uku Paal.
Mew gull Kalakajakas Larus canus
The mew gull is the only gull species that is marked with colour rings in Estonia. Lead by Sven Onno, colour ringing of mew gulls started in Matsalu already in 1962. It was at the same time also the first project with colour ringing of birds that was started in Estonia.
On the small isle of Kakrarahu near Puise nina, mew gulls are studied and in connection with this also marked with coloured rings even today, directed by Kalev Rattiste. Birds ringed here get a white polymer ring on the leg where the code, in black print, starts with the letter “P”. About these birds almost every day information about refinds arrives from the wintering areas in the Netherlands, Great Britain and Germany.
For Estonian birdwatchers it is certainly worthwhile in spring to check the fields where mew gulls often forage. By this the refinding of the birds can increase significantly in Estonia too.
Of the mew gulls ringed abroad most often specimens with yellow or red polymer rings are seen
Mew gull ringed at Kakrarahu near Puise foraging in field. The mew gulls ringed within the project mentioned above have a white polymer ring on their legs where the code, in black, always starts with the letter “P”.
Yellow polymer rings with 3 or 4-letters/numbers mainly originate from Denmark. Mew gulls ringed with red polymer rings are generally birds ringed in Germany. These rings have a white text with a code beginning with the letter „A”.
Black-headed gull Naerukajakas Larus ridibundus
In winter the black-headed gull is a much less abundant species. Because of this the best time for checking rings of black-headed gulls is early spring (March, April) and late summer (July, August). Most coloured rings of this species are white, with a letter/number code. These gulls have been ringed in great numbers in the wintering areas in Poland and Denmark.
Most of the black-headed gulls seen with coloured rings in Estonia are ringed with a white polymer ring. The bird with the “LYE” code above has originally been ringed with a metal ring in Malmö in Sweden. The bird, that later also got a polymer ring on its leg in the Netherlands, has been seen for several summers in Haapsalu and probably nests in a colony on the isles there. /Photo: Tarvo Valker
There are also occasional finds of dark-headed gulls ringed in Germany, Hungary, Russia, Spain, Sweden, Finland, the Netherlands and Croatia. Much less frequently dark-headed gulls with red, yellow or blue polymer ring are seen.
Keep an eye on the “ringfinder” blog: LINK