Western house martin

The western house martin, also called the common or northern house martin or simply house martin, is a migratory passerine of the swallow family that breeds across temperate Eurosiberia, North Africa and west central Asia before wintering in sub-Saharan Africa and southwestern Asia. It hunts flying insects on the wing and is recognized by its blue head and upperparts, white rump and pure white underparts. The species nests in colonies, building a closed cup of mud pellets under eaves or similar ledges on buildings, a habit reflected in both its scientific and common names, and it faces predation from the Eurasian hobby as well as internal parasites and external fleas and mites. With a global range of about 30.8 million square kilometres and a European population of 22 to 47 million birds, it is classified as Least Concern, though numbers are declining in Europe and Britain.