quiet call, the short-toed treecreeper is easily overlooked as it hops mouse-like up a vertical trunk, progressing in short hops, using its stiff tail and widely splayed feet as support. Nevertheless, it is not wary, and is largely indifferent to the presence of humans. It has a distinctive erratic and undulating flight, alternating fluttering butterfly-like wing beats with side-slips and tumbles. It is solitary in winter, but in cold weather up to twenty or more birds will roost together in a suitable sheltered crevice, or in a star formation under eaves of buildings. Status and conservation This species has an extensive range of between 1–10 million square kilometres (0.4–3.8 million square mi). It has a large population, estimated at between 4.1–14 million individuals. Population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (declining more than 30% in ten years or three generations). For these reasons, the short-toed treecreeper is evaluated as Least Concern. It is common through much of its range, but is rare in the Caucasus and on the smaller Channel Islands. In the west of its range it is spreading north through Denmark, where it first bred in 1946. References External links Ageing and sexing (PDF; 0.78 MB) by Javier Blasco-Zumeta & Gerd-Michael Heinze Feathers of Short-toed treecreeper (Certhia brachydactyla) Article on the identification of common and short-toed treecreepers (in German with an English summary) short-toed treecreeper Birds of Europe short-toed treecreeper short-toed treecreeper