Removal and predation of Quercus liaotungensis acorns by animals

Two types of acorns (fresh, current-year acorns and old, previous-year acor ns) of Quercus liaotungensis were used under two different situations (nigh t and day) to examine the removal and predation by animals in the field. Th e acorns disappeared very fast. During the day, all of the 280 'this-year' acorns (TA) and all of the 140 'last-year' acorns (LA) were removed by anim als within 6 h and 5 h, respectively, after acorns were pur in place. At ni ght, all of the 280 TA acorns were removed by animals within 10 h after aco rns were distributed, and 71 out of 140 LA acorns were removed within 10 h. Animals consumed a small proportion of acorns in situ (11.8%). The number of TA acorns consumed in situ at night was higher than that during the day. During the day, the number of LA acorns consumed in situ was significantly higher than TA acorns. This result suggests that the most important harves ters of Q. liaotungensis during the day were visually orientated diurnal an imals, and the most important harvesters ar night were olfactorily orientat ed nocturnal animals. Furthermore, the latter are more efficient than the f ormer at finding and harvesting acorns, because they spend less energy on h arvesting the same number of sound acorns.