Study Of Relationships Between The Activity Of Rhinolophus Ferrumequinum And Its Food Resources

This paper first reported that the relationships between the activities of the greater horseshoe bats(R. ferrumequinum) and food resources.During the peak of foraging activity of the greater horseshoe bats at night, acoustic survey was used to obtain the activity frequency of R.ferrumequinum,and light trap was used to capture insect prey at every sampling site Simultaneously.The insects were identified to family level. Correlation,one way AVONA and regression analysis were used to reveal the relationships between the activity frequency of R.ferrumequinum and food resources,and the variations of the relationships with the months and different time phases at night.The diet of R.ferrumequinum was obtained by fecal analysis in June,July and August.The main results are as follows:1.The activity frequency of bats were significantly correlated with insect resources.Correlation analysis results indicated that bat activity was significantly correlated with Lepidoptera abundance(r=0.831,p=0.011, n=8),total insect abundance(r=-0.812,p=0.014,n=8),insect biomass(r=0.848,p=0.008,n=8). However,there were no significant correlation with the percentage of Lepidoptera(r=-0.571,p=0.140,n= 8),Coleopteran abundance(r=0.343,p=0.406,n=8),the percentage of Coleopteran(r=-0.376,p=0.358, n=8) and insect diversity(r=0.231,p=0.582,n=8).2.Coleoptera and Lepidoptera were the main food items of R.ferrumequinum.And the diet was varied with months.In June,volume percentage of Lepidoptera and Coleoptera were 68.99%and 30.07%,respectively.In July,volume percentage of Lepidoptera decreased to 57.25%,and volume percentage of Coleoptera increased to 39.07%.In August,volume percentage of Lepidoptera was 35.15%,and volume percentage of Coleoptera was 51.29%.Volume percentage of Hymenoptera in August was 11.2%,which was higher than volume percentage in June and July.3.The relationships between bat activity frequency and food resources varied with months.The result showed that bat activities in June were significantly correlated with Lepidoptera abundance(p=0.015＜0.05) and total insect abundance(p=0.031＜0.05),and were not significantly correlated to other insect parameters, Bat activities in July were only correlated with Lepidoptera abundance(p=0.008＜0.05) significantly.In August bats activities were not significantly correlated with all the insect parameters.Stepwise regression analysis between volume percentage in diet and percentage of available insect in the environment indicated that there was a significant correlation in June(p =0.048~*) and July(p=0.013~*),while there was no significant correlation in August(p=0.166) Hence we can deduced that Rhinolophus ferrumequinum foraged randomly in June and July,and foraged selectively in August. 4.The relationships between bat activity frequency and food resources varied with time phase at night:In the fourth time phase of the night in June,bat activities were significantly correlated with Lepidoptera abundance(p=0.015<0.05),total insect abundance(p=0.031<0.05) and insect biomass(p=0.012<0.05), and not with other parameters.In the third time phase of the night in July,the bat activities were only significantly correlated with Lepidoptera abundance(p=0.008<0.05) and the total insect abundance(p= 0.001<0.05).In the fourth time phase of the night in August,bat activities were significantly correlated with Lepidoptera abundance(p=0.001 <0.05),total insect abundance(p=0.01<0.05) and insect biomass(p=0.021<0.05),and there was no correlation with other parameters.