A Comparison Of Activity Rhythm And Time Budgets Of Two Groups Of Rhinopithecus Roxellana In Minshan Mountains

Animals living in different regions will adopt different behavioral adaptation strategies for varied habitats.Sichuan snub-nosed monkey(Rhinopithecus roxellana)is a rare and endangered species,endemic to China.However so far,as one of the main distribution areas,the related study of Rhinopithecus roxellana in Minshan Mountains is very scarce.To further understand the survival strategies of different geographical populations in this region,we compared the activity rhythm and time budgets of two groups of Rhinopithecus roxellana in Tangjiahe National Nature Reserve(NNR)and Baihe NNR,Sichuan,using instantaneous scanning sampling method,from July 2015 to October 2017.The main results showed as follows:1.There were two peaks of foraging of Rhinopithecus roxellana in the morning(8:00 to 10:00)and afternoon(13:00 to 17:00),with one resting peak at noon(12:00 to 13:00),and there were two peaks of moving of Rhinopithecus roxellana in the morning(10:00 to 11:00)and afternoon(15:00 to 17:00)in Tangjiahe NNR.Similarly,there were two peaks of foraging of Rhinopithecus roxellana in the morning(8:00 to 10:00)and afternoon(15:00 to 18:00),with one resting peak at noon(12:00 to 13:30)and one moving peak in the afternoon(14:00 to 16:00)in Baihe NNR.There was no clear peak of other behavioral types.Although the activity rhythm of Sichuan snub-nosed monkey was varied among seasons,it did not change the general trend of daily activity rhythm.We found that there were little differences in the rhythm of moving and resting between the two populations of Rhinopithecus roxellana by comparison.But the peak of foraging in Baihe NNR is earlier in the morning,and later in the afternoon than that in Tangjiahe NNR,and the rhythms of other types of behavior was also different in two places.2.Rhinopithecus roxellana spent 40.80%,30.90%,23.67% and 4.63% of daytime on foraging,moving,resting and other behaviors,respectively,all year around in Tangjiahe NNR.There were significant differences among seasons in time budgets for foraging and other behavior(P < 0.05).The maximum amount of time spent on foraging and other behavior occurred in winter and summer,respectively,accounting for 48.55% and 7.03%.However,there were no significant differences in time budgets for moving and resting between the two populations(P > 0.05).Rhinopithecus roxellana spent 41.54%,32.90%,22.71% and 2.85% of daytime on foraging,moving,resting,and other behaviors,respectively,all year around in Baihe NNR.There were significant differences in time budgets for foraging,moving and resting among seasons(P < 0.05).The maximum amount of time spent on foraging,moving and resting was winter,spring and autumn,respectively,accounting for 48.99%,37.19% and 32.68%.There was no significant difference in time budgets for other behavior among seasons(P > 0.05).3.Significant difference was only found in other types of behavior between the two populations all year around(P < 0.01).Further analysis showed that the time allocated for other behaviors of Rhinopithecus roxellana in Baihe NNR was significantly less than that in Tangjiahe NNR in spring,summer and autumn(P < 0.05).In autumn,the time allocated for foraging of Rhinopithecus roxellana in Baihe NNR,accounting for 45.09%,was significantly more than that in Tangjiahe NNR,accounting for 36.44%(P < 0.05).In winter,there were no significant differences in activity time budgets between the two populations(P > 0.05).4.The activity time budgets were different among sex-age groups of Rhinopithecus roxellana.The time allocated for feeding of the adult females was significantly more than that of other sex-age groups(P < 0.05),accounting for 28.53% and 45.09% in Tangjiahe and Baihe NNR,respectively.The juvenile and infant monkeys spent significantly more time on moving than that of adults(P < 0.05),and the juvenile spent the most time on moving,accounting for 48.76% and 46.14% in Tangjiahe and Baihe NNR,respectively.The juvenile and infant monkeys spent more time in other types of behavior than that of adults.The adult females also spent more time in other types of behavior than adult males.In order to avoid energy losses caused by unnecessary activity,adult monkeys spent more time on resting than that of juvenile and infant monkeys.In addition,there were significant differences in activity time budgets of the same sex-age group of Rhinopithecus roxellana among seasons.