Study Of The Echolocation Calls Of Rhinolophus Ferrumequinum In Different Habitats

Rhinolophus ferrumequinum has been marked as an endangered species in Europe and has been listed as an LR/nt species into IUCN Red List of Threatened Species. Study of echolocation calls of R. ferrumequinum is one of major fields in bat study. From June to October 2007, we carried out our experiment in Luotong mountain reservation in Jilin province, China. We recorded and analyzed the echolocation calls of Rhinolophus ferrumquinum using Avisoft Bioacoustics USG 116 and Avisoft-SASLAB PRO (Avisoft Bioacoustics, Berlin, Germany) in 8 different habitats, investigated the ecological characteristics of 8 habitata including vegetational, climatic and topographical characteristic. Used SPSS14.0 statistical analysis software to analysis the parameters of echolocation calls and applied principal component analysis and pearson correlation analysis method with ecological characteristics, discussed the adaptability of echolocation call and ecological characteristics. The conclusions were as follows:1. Echolocation calls of Rhinolophus ferrumequinum were FM/CF/FM type in different habitats, A One-Way Analysis of variance indicated the calls were significantly (P < 0.05).With the increasing of the clutter degree of habitats, the bandwidth and peak frequency gradually depress, but the pulse duration and inter-pulse interval gradually increase. The echolocation calls of R. ferrumequinum in relative habitats was characteristic by relative low frequency, narrowband and long duration and inter-pulse interval, whereas R. ferrumequinum use high frequency, broad bandwidth and short duration calls in cluttered habitats. The pulse duration and inter-pulse interval of one complete sound rangeabilities were 40.17±7.09 ms-67.23±7.04 ms,34.19±10.49 ms-50.68±6.14 ms, respectively. The variance scope bandwidth of up-regulation and down-regulation were 3.18 kHz and 4.71 kHz, the FM₁ starting frequency and FM₂ termination frequency were 55.74 kHz-59.49 kHz and 57.39 kHz-61.49 kHz. The peak frequency in different habitats sort was Cluttered broad-leaved woodland > stream > Mixed woodland > Open broadleaved woodland > Coniferous woodland > rock > Resident site > Pond.2. In the environmental factor components analysis in clutter habitats, the factor loading coefficient in every principal component were comparatively large: height below the canopy, areas of canopy, arbor height; average shrub height; number of plant. The Pearson correlation analysis and two-tail significance test of the five parameters and echolocation parameters, indicated significant negative correlation between FM₁ bandwidth, FM₂ bandwidth with arbor height(r = -0.948,-0.825;P < 0.05), the FM₁ starting frequency, FM₂ termination frequency with areas of canopy(r = -0.967,-0.958;P < 0.05); The pulse duration and inter-pulse interval with average shrub height(r = -0.911,-0.990;P < 0.05);peak frequency with number of plant(r = 0.756,P < 0.05), significant positive correlation between pulse duration and height below the canopy(r = 0.870,P < 0.05).3. In the climatic and topographical factor components analysis, the factor loading coefficient in each principal component were comparatively large: air relative humidity, altitude,slope direction. The Pearson correlation analysis and two-tail significance test of the five parameters and echolocation parameters, indicated significant negative correlation between FM₁ starting frequency, FM₂ termination frequency, peak frequency with air relative humidity(-0.776,-0.875,-0.794,P < 0.05).It is thus evident that echolocation calls were certainly diversity in different habitats. Many kinds of echological factor (vegetation factor, climatic and topographical factor) had effect on echolocation calls. The echolocation call had phenotypic flexibility and eco-adaptability. These characteristics determined the habitat use degree and the natural resources which they used of Rhinolophus ferrumquinum.