Smaller groups usually consist of an unmated female courted by unmated males. In autumn and winter large numbers of acorns are brought back to the jays' territories and hidden for future retrieval. It has been estimated that a single jay could 'plant' up to 3000 acorns in a single month. On occasions, jays become bold, visiting garden bird tables for scraps. Several correspondents made reference to this habit when reporting siskins and long-tailed tits feeding on peanuts.
Jays are reluctant to leave the shelter of woodlands.
When venturing across clearings and roads, they do so one at a time, the following bird not breaking cover until the previous one has made it safely across. Flight is laboured and flapping, but when on migration it is much more direct. Irruptions of northern jays are reported from time to time following acorn crop failure. During the autumn of 1993 an arrival of continental jays became apparent during late September with further arrivals until mid-October. As many as 90 headed west at Sheringham during a single day.