ナミエヒナコウモリの繁殖期における採食活動と生後の成長について

抄録

Adult females of Vespertilio superans superans arrived at a rock tunnel on an islet of Ohzukue-jima in April to form matenitycolony. Feeding activity of pregnant females began at about 10 minutes after sunset and continued until about 0200 hr, and that of lactating females had two peaks with a major one soon after sunset and a minor one before sunrise, while that of young was intermittent. Parturition occurred from late June to early July. Litter size averaged 2.0. Body weight of newborn young was relatively light, being ca.12% of the weight of postpartum females. The low ratio seemed to be closely correlated to the high frequency of multiple births and high wing loading of the mother bat. Lactation lasted an average of 35 days. Deciduous teeth (di 2/3,dc 1/1,dprn 2/2=22) present at birth were replaced by permanent dentition at 24 to 26 days of age. Eyes opened at 8 to 12 days, and afterwards the growth was accelerated. Most of the young females became gravid in the next summer. The adult females left the nursery colony soon after independence of their young ; and next the majority of young males departed. The remainder young emigrated in the middle or last decade of September.