COLOUR-RINGING OF WHITE-TAILED EAGLES

The programme of colour-ringing of White-tailed Eagles was initiated in 1976 in Scandinavian countries. Within its frames, exclusively nestlings were colour-ringed. Each individual received two rings. A standard ring, with the number and address of the country's ringing centre, was put on the right tarsus. This ring was in the colour assigned to the given country. Exceptionally in Sweden and Finland, different colour codes were used to distinguish birds from the populations inhabiting Lapland, the Baltic Sea coast and lake districts remote from the seashore. The other coloured ring was placed on the left tarsus of a nestling. It had the same colour in all countries but a different one in each particular year. Originally, in 1976-1981, on the left leg a unicoloured 15-mm-high ring was put, whereas since 1982 a two-coloured 18-mm high ring has been used. For a couple of years these rings have been bearing an engraved individual number, composed of a letter and three digits. Application of two rings enables to get precise information on the age of the bird and the country it comes from. Until 1999, 7 544 White-tailed Eagles had been colour-ringed in Europe.

When observing a colour-marked White-tailed Eagle, it is essential to note the colour of the upper and lower part of the ring, and to estimate the bird's age (ad., subad., imm.), also by deciphering the code. Any information concerning observation of a ringed bird should be sent to the Department of Ornithology, Polish Academy of Sciences, in Gdańsk (Nadwiślańska 108, 80-680 Gdańsk 40,
(e-mail: ring@stornit.gda.pl).

So far in the western part of Poland birds from Germany and Estonia have most frequently been observed, whereas in the eastern part ones from Lithuania and Belorus. The White-tailed Eagles from Poland were recorded in Germany, France, and even in northern Italy. A bird carrying a Polish ring was observed to have nested in central Germany.

Each birdwatcher can immediately find the country of origin and age of the White-tailed Eagle observed making use of the following code: