stan Boutin, Zena Tooze, Karen Price; Post-breeding dispersal by female red squirrels (Tamiasciurus hudsonicus): the effect of local vacancies. Behav Ecol 1993; 4 (2): 151-155. doi: 10.1093/beheco/4.2.151
Red squirrels (Tamiasciurus hudsonicus) defend food-based territories year round, and juveniles must acquire a territory before winter to survive. We experimentally removed territory owners during the time that juveniles were becoming independent to examine the effect of local vacancies on dispersal patterns. Juveniles attempted to take over removal territories most frequently. However, females with offspring still on the natal territory actually took over twice as many territories as juveniles. These females did not appear to move because of low reproductive potential or to increase territory quality. Instead, moving to a removal territory allowed more of their offspring to remain on the natal territory, which appeared to increase juvenile survival.