Experimental Study on Hibernation Patterns in Different Ages and Sexes of Daurian Ground Squirrel(Spermophilus Dauricus)

There are differences in the hibernation patterns of different sexes and ages Daurian ground squirrel in the field.To elucidate whether these differences associate with the energy availability during hibernation,we grouped the animals into adult males,adult females,juvenile males and juvenile females.The energy storing before hibernation,the hibernation patterns and body mass changed during hibernation season were measured in the laboratory.Our results showed that the males generally entrance into and arousal from torpor earlier than the females,and the adults earlier than the juveniles.As to adult animals,the duration of hibernating season and the accumulated torpid duration were all shorter than juvenile animals.These results are consistent with the hibernation patterns showed in the field in this species.The maximum body mass,which represents the energy storage,was also larger in adults than juveniles,and larger in males than females.The dates when animals got maximum body mass also followed the similar time sequence.The different hibernation patterns may essentially affected by energy storage in the body and the ground squirrels could reduce the expression of hibernation while enough energy are available.