Pigeon with letter (Bulgaria 1946)

Stamp Pigeon with letter it reflects the thematic directions:

The homing pigeon, also called the mail pigeon or messenger pigeon, is a variety of domestic pigeons (Columba livia domestica) derived from the wild rock dove, selectively bred for its ability to find its way home over extremely long distances. The rock dove has an innate homing ability, meaning that it will generally return to its nest using magnetoreception. Flights as long as 1,800 km (1,100 miles) have been recorded by birds in competitive pigeon racing. Their average flying speed over moderate 965 km (600 miles) distances is around 97 km/h (60 miles per hour) and speeds of up to 160 km/h (100 miles per hour) have been observed in top racers for short[clarification needed] distances.

Columbidae (/kəˈlʌmbɪdiː/ kə-LUM-bih-dee) is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily feed on plants, and can be taxonomically divided amongst granivores, that feed mostly on the ground on seeds, and frugivores, that feed mostly on fruits, from branches. The family occurs worldwide, often in close proximity with humans, but the greatest variety is in the Indomalayan and Australasian realms.