Here we have a neat cover with a se-tenant strip of WWF stamps showing birds. It is part of a sheet of 8 issued on 31 Oct 2003. The stamps feature the Osprey, a bird that preys on fish and catches them with its talons. The osprey is much admired by many for its gracious swoops and sharp eyes. Ospreys are cousins to eagles, which also prey on fish in a similar manner. More on the osprey and on this issue from the Poczta Polska wesbite:
Osprey - cousin of the eagle - is one of the most splendid carnivores birds that is possible to see in Poland. His weight can be even one and a half kilo. It has a slim silhouette and long wings that he does not spread quite horizontally when flying, like other eagles, but keep them slightly tucked up.. From the upper side completely dark, the bottom side and the head is white. There is a dark color strip running by his eye.
They are hunting on fishes as we can see from the name. It does it however in a different way then most of other birds feeding themselves with fishes. It catches the fishes with his legs. The hunting is very spectacular. He glides and when he sees a potential prey he falls down and attacks with his claws, diving.
Osprey is a species under protection in Poland. There is now only about 30 couples of ospreys in Poland, mainly in north of the country. In Upper Silesia it is possible to see them during their transit flights especially in September and October. At this time there are transiting birds from Scandinavia. A complete protection of its nestling places and interdiction of killing all carnivores birds during their transits allowed to protect the population of the osprey and now the declining of their number has been stopped.
The introduced just now into circulation post stamp is the second one after the issue from 1985.
"Wild animals under protection - the wolf", a set issue by Polish Post in collaboration with the World Wide Fund for Nature.
Polish Post got the license to use the picture of Panda and the trade mark of WWF, which are on our stamps, authorization granted by WWF, the owner of the registered trade mark.
The World Wide Fund for Nature has been founded in 1961 as an international organization which task was to hold up and then to revert the processes of degradation of the natural environment of our planet. Besides the efforts in preservation of the nature WWF works on awaking the social consciousness of private, social and political people.
[sic] on all the awkward English, but I guess the excerpt is quite understandable as it is.
The stamps were machine-canceled at Krakow, the formal national capital and one of the largest and oldest of Poland's cities with a history of more than a thousand years, in March of 2008.