Usman K, Subbaraj R, Subramanian P
Department of Animal Behaviour, School of Biological Sciences, Madurai Kamaraj University, Madurai 625 021 INDIA.
Behav Processes. 1990 Jun;21(2-3):81-94. doi: 10.1016/0376-6357(90)90017-A.
The activity cycle of a colony of about 1500 bats Rhinopoma hardwickei was studied in 1978-1979 in Madurai, India. Variations in the times of emergence of foraging paralleled variations in sunset and return to the roosting paralleled sunrise. The releasing stimulus for departure of the first outflyer on clear evenings is the crossing of a lower threshold value of its relative decrease. Return to the roost usually occurs at a lower light intensity than the departure. In summer the nightly rate of emergence is relatively higher than in winter. The seasonal changes of phase angle differences of onset (Ψ0) and end (Ψe) of activities are roughly mirror images. The time of midpoint of foraging activity however, stays relatively constant.
1978 - 1979年在印度马杜赖对一群约1500只哈氏菊头蝠的活动周期进行了研究。觅食外出时间的变化与日落时间的变化平行，返回栖息地的时间与日出时间平行。在晴朗的夜晚，第一只外出蝙蝠离开的释放刺激是其相对减少量越过较低阈值。返回栖息地通常发生在比离开时更低的光照强度下。夏季夜间外出率相对高于冬季。活动开始（Ψ0）和结束（Ψe）的相位角差的季节变化大致呈镜像。然而，觅食活动中点的时间保持相对恒定。
