Flocking behavior analysis of reeves's pheasant (Syrmaticus reevesii) using infrared cameras
The flocking behavior of animals has long been an important topic in wildlife research.Such information should be helpful to develop a comprehensive understanding of the natural ecology and biology of wildlife,including pheasant species,which should be beneficial to protecting pheasants in the wild.However,some species of pheasants are naturally vigilant with concealed behaviors,making it rather difficult to conduct field studies on their flocking behavior.One such pheasant species is Reeves's pheasant (Syrmaticus reevesii),and sparse quantitative information on its flocking behavior in the field has been collected to date.In order to survey the flocking behavior and its geographic variation of Reeves's pheasant,we used camera trapping to monitor the flocking behavior at two sites:Pingjingguan Village,Hubei Province and Dongzhai National Nature Reserve,Henan Province.These infrared cameras were set up in the field from March 2013 to March 2014,which provided an opportunity to understand the annual rhythm of flocking behavior of this pheasant at these two sites.Based on the results of radiotracking studies previously conducted at the same study sites,we established a 1 × 1 km plot in each site,and then placed 25 infrared cameras in each plot.The working days of all cameras added up to 12412 days,and we obtained 24374 video clips in the field from these cameras.In particular,a total of 1361 of these clips captured Reeves's pheasant,including 525 clips and 836 clips in Dongzhai National Nature Reserve and Pingjingguan Village,respectively.We determined the ratio of the numbers of individual clips showing flocking behavior of the pheasant (m) to the total number of clips (M),and the ratio of the number of pheasants captured by the clips (n) to the total number of clips showing pheasant flocking behavior (m).Our results showed that a flock with two individuals occupied the largest portion of all flocks at these two sites,accounting for 68.23% and 72.79% of the total in Pingjingguan Village and Dongzhai National Nature Reserve,respectively.Three types of flocks,i.e.only-males,only-females,and mixed malesfemales,occurred in these two sites,and single-sex flocks dominated the flocks in the field,whereas the mixed male-female flocks accounted for only a small portion of the total flocks.In particular,Pearson's chi-squared test showed that there were no significant differences in the numbers of flocks between the two sites,whereas a significant difference was found in flocking types between the two sites.Moreover,the encounter rate of only-female flocks in Pingjingguan Village was higher in summer and autumn,and that of only-male flocks was higher in spring and autumn.Similarly,the only-female flocks in Dongzhai National Nature Reserve appeared occasionally in summer and autumn,and only-male flocks mainly appeared in spring.In addition,the flocking intensity of the whole year reached the peak in the non-breeding period at both study sites.On the other hand,the lowest flocking intensity at Pingjingguan and Dongzhai National Nature Reserve occurred in the breeding period and at the early stage of the breeding period,respectively.In the breeding period,these two study sites showed similar flocking intensities.The peak of the flocking rate of this pheasant in Dongzhai and Pingjingguan occurred in winter and the early stage of the breeding period,respectively.Reeves's pheasant showed a highly significant preference for shrub and bamboo,while avoiding broadleaf mixed forests,fir,and arbor in Pingjingguan Village.It had a highly significant preference for theropencedrymion and coniferous forests,while avoiding fir and broadleaf forests in Dongzhai National Nature Reserve.