During the darkest days of Alaska’s winter, black-capped chickadees stuff themselves with enough seeds and frozen insects to survive 18-hour nights.

Where chickadees spent those long nights was a mystery until a University of Alaska Fairbanks biologist tracked them.

Since the late 1970s, the University of Alaska Fairbanks’ Geophysical Institute has provided this column free in cooperation with the UAF research community. Ned Rozell ned.rozell@alaska.edu is a science writer for the Geophysical Institute. A version of this story ran in 2003.