The Snowy Owl has recently been
listed as globally VULNERABLE. See: http://datazone.birdlife.org/species/factsheet/snowy-owl-bubo-scandiacus or http://www.iucnredlist.org/details/22689055/0. Population size and the extent
of the declines are both poorly understood; however, despite the uncertainty,
there is sufficient evidence for a listing of Vulnerable. We don’t really know
why the numbers are declining but reduced food supply (perhaps due to climate
change) and the high rate of collisions with vehicles and infrastructure have
been suggested.