Wallcreeper

The wallcreeper (Tichodroma muraria) is a distinctive small bird living in the high mountains of the Palearctic, from Europe to China, recognized by its blue-grey plumage and striking crimson wings, which are particularly bright on the covert feathers and base of the primaries and secondaries. This bird, measuring between 15.5 to 17 cm long and weighing 17 to 19 grams, is the only living member of its genus and family, Tichodromidae. While there's some debate among scientists about its exact taxonomic placement, it's closely related to nuthatches. Wallcreepers can be found at altitudes of 1,000 to 3,000 meters but may move to lower elevations in winter, where they are often seen on buildings. Their diet consists mainly of insects and spiders, which they hunt on rock faces. Wallcreepers are territorial; pairs defend breeding territories in summer, while individuals defend separate feeding areas in winter. They breed in crevices, with the female constructing a nest where she lays 4-5 white eggs, incubated for about 20 days. Both parents care for the altricial young for around 28-30 days. Despite being generally quiet, both sexes can sing, with the male also singing while climbing. The two recognized subspecies differ slightly in coloration, with the Himalayan variant being darker.