Okay, here’s a slightly deceptive Guinness Book of World Records award for the Shortest Bird Migration:
In stark contrast to the thousands of kilometres flown by certain migrating birds, such as the Arctic tern (Sterna paradisaea), the world’s shortest migration is that of North America’s blue grouse (Dendragapus obscurus). During the winter, it inhabits mountainous pine forests, then when nesting time begins in springtime it descends a mere 300 m to deciduous woodlands in order to feed upon the early crop of seeds and fresh leaves.
This bird is commonly called the dusky grouse, and looks like this (male above, female below):
Well, 300 vertical meters is longer than that horizontally, but if you count this as a real migration, then it’s still probably the shortest one known. Curiously, the Cornell bird site is less informative than Wikipedia here on the “migration”:
Their breeding habitat is the edges of conifer and mixed forests in mountainous regions of western North America, from southeasternAlaska and Yukon south to New Mexico. Their range is closely associated with that of various conifers. Their nest is a scrape on the ground concealed under a shrub or log.
They are permanent residents but move short distances by foot and short flights to denser forest areas in winter, with the odd habit of moving to higher altitudes in winter.
These birds forage on the ground, or in trees in winter. In winter, they mainly eat fir and douglas-fir needles, occasionally also hemlockand pine needles; in summer, other green plants (Pteridium, Salix), berries (Gaultheria, Mahonia, Rubus, Vaccinium), and insects(particularly ants, beetles, grasshoppers) are more important. Chicks are almost entirely dependent on insect food for their first ten days.
Now we have many readers who are birders. Is Guinness right in counting this short movement as a “migration”?