Thank you Andrew for this postcard from Russia. Both bird stamps used were issued in 2006.
Ross's Gull (Rhodostethia rosea): This small gull, which is named after the British explorer James Clark Ross, can be found in arctic north part of North America and in northeast Siberia. It migrates south but on a short distance. It can eat any small prey.
Siberian Crane or Snow Crane (Grus leucogeranus): It can be found in wetlands in arctic Russia and western Siberia. It migrates in China, Iran and India. It eats aquatic plants. It is classified as critical.

Thank you Jemma for this aerogamme from Australia.
Wandering Whistling-duck (Dendrocygna arcuata): This whistling duck can be found in subtropical and tropical Australia, in the Pacific Islands, Indonesia, Philippines and Papua New Guinea. It has three subspecies. It is classified as least concerned and it feeds on grass, waterlillies, water plants, aquatic vertebrates and insects. It is a migratory species.

Merry Christmas to everyone! Here is a pre-paid card from Poland. It was issued in 2006 and it is part of a series showing the beauty of this country. White Storks (Ciconia ciconia) are one of them.

Thank you Boben for this nice registered cover from India. The m/s was released in 2010. Both the birds it shows are very common. About the Rock Pigeon you can have a look in older posts.
House Sparrow (Passer domesticus): It can be found in most of Europe and Asia. It has 12 subspecies. It feeds mostly on seeds and insects but it is also an opportunistic bird.

Hello everyone, for my first post in December I chose a WWF cover from Croatia. The stamps used for postage were issued in 2006 and they are a part of a set of four. The whole set is devoted in Little Tern (Sterna albifrons) which I presented in a previous post. Thank you Dragan for the cover.