Roosttime restlessness in captive American Robins (Turdus migratorius)

All-day observations of captive American Robins (Turdus migratorius) revealed that the birds became extremely active at dusk, the time when wild Robins typically fly some distance to a communal roost site. This roosttime restlessness occurred during every month of the year, and so was distinguishable from the migratory restlessness that the birds displayed during early morning hours of spring months. The present observations also uncovered a recapitulation effect, in that the changes in activity level that occurred within any single day (from dawn through dusk) tended to parallel the changes in activity level that occurred across the year (from spring through winter).