The boreal owl (Aegolius funereus) is a small owl. In Europe, it is typically known as Tengmalm's owl after Swedish naturalist Peter Gustaf Tengmalm or, more seldomly, Richardson's owl after Sir John Richardson. This species is a part of the larger grouping of owls known as typical owls, Strigidae, which contains most species of owl. The other grouping is the barn owls, Tytonidae. Due to its shyness and evasive reaction to human activities, nocturnal habits and preferred inaccessible taiga forest habitat, it ranks as one of the, if not the, least known owls in both North America and Europe.