Geographical isolation may lead to the populations having different ecological characteristics. Geographic isolation have been known to cause echolocation call differences in bats. In order to look at geographic differences of echolocation calls of Great Horseshoe Bats (Rhinolophus ferrumequinum), populations of inland and Jeju island habitats were examined in Korea. The study areas were some abandoned mines in the inland and caves of Jeju island, which were known as rest sites of Great Horseshoe Bats during the active season. Recording was done in two ways: Hand-held, Free-flying. Recording pulse was analyzed into five parameters: Maximum Frequency (FMAX), Minimum Frequency (FMIN), Peak Frequency (PF), Duration (D), Inter pulse Interval (IPI). Interestingly, The present study shows that the difference in echolocation between the inland and island populations. The PF of bats inhabited inland was 69 kHz. but, the PF of bats inhabited island (Jeju) was 71 kHz. There was a difference between regions. Discriminant analyses also showed clear difference between the inland and the island populations. Especially, PF of Korea population is lower than that of Europe (82 kHz) and higher than that of Japan (65 kHz).
The purpose of this study was to identify the characteristics of the home range and habitat use of Rhinolophus ferrumequinum individuals that inhabit urban areas. The bats were tracked using GPS tags. For analysis of the home rage, Minimum Convex Polygon (MCP) and Kernel Home Range (KHR) methods were used. The landscape types of all positional information were analyzed using ArcGIS 9.3.1 (ESRI Inc.). The average home range of 16 R. ferrumequinum individuals was 68.63 ± 25.23 ha, and the size of the overall home range for the females (85.49 ± 25.40 ha) was larger than that for the males (51.76 ± 8.30 ha). The highest average home range for the males was found in August (61.21 ± 0.01 ha), whereas that for the females was found in September (112.27 ± 5.94 ha). The size of 50% KHR ranged from a minimum of 13.26 ha to a maximum of 31.00 for the males and a minimum of 8.02 ha to a maxinum of 42.16 ha for the females, showing no significant differences between the two sexes. In addition, males and females showed no differences in the size of 50% KHR in the monthly comparisons. However, the females showed differences in the size of their core area between periods before and after giving birth. The comparisons between 100% MCP and 50% KHR showed that the types of habitats used by R. ferrumequinum were mostly forest areas, including some farmlands. In addition, comparisons with a land cover map showed that the proportion of broad-leaved forests was the highest, followed by that of mixed forests.
The greater horseshoe bat (Rhinolophus ferrumequinum) is distributed throughout Europe, Africa, Australia, and South Asia. It habits mainly in the cave in small groups and forming communities in late spring. It has interesting reproductive behavior because it keeps sperm for a few months in female reproductive tracts and then those sperms attend in fertilization. This breeding pattern is a sperm storage type and belongs to Rhinolophidae or Hipposideridae. The greater horseshoe also habits in Korea. However, the reasons of reproductive behaviors has not much uncovered. In this study the characters of ovary and the levels of steroid hormones were investigated from September to November. The histological, ELISA, and immunohistochemical methods were employed. The pre-ovulatory follicle was detected only at October sample. On the other hand, the blood level of testosterone was not detectable but the levels of 17β-estradiol and progesterone were exist within the detectable range. E2 and P4 levels were peak in October. Besides, the key enzymes for estradiol synthesis, CYP17 and CYP19 were localized in the theca layer and granulosa cells, respectively. October is known as mating time in this species. However, progesterone receptors could not detect at this period. Put together, it is suggested that, the increase of estrogen and the absence of progesterone receptors on preovulatory follicle is the cause of the mating without ovulation. The understanding of the expression regulation in this system will be base of the understanding the anovulation in mammals.
In this study, we analyzed the changes in the echolocation and prey-capture behavior of the horseshoe bat Rhinolophus ferrumequinum from search phase to capture time. The experiment was conducted in an indoor free-flight room fitted with an ultra-high-speed camera. We found that the bats searched for food while hanging from a structure, and capturing was carried out using the flight membrane. In addition, it was confirmed that the mouth and uropatagium were continuously used in tandem during the capturing process. Furthermore, using Constant Frequency (CF), we confirmed that the prey catching method reflected the wing morphology and echolocation pattern of R. ferrumequinum. The echolocation analysis revealed that the pulse duration, pulse interval, peak frequency, start-FM-bandwidth, and CF duration decreased as the search phase approached the terminal phase. Detailed analysis of echolocation pulse showed that the end-FM bandwidth, which increases as it gets nearer to the capture time of prey, was closely related to the accurate grasp of the location of an insect. At the final moment of prey capture, the passive listening that stopped the divergence of the echolocation was identified; this was determined to be the process of minimizing the interruption from the echo of the echolocation call emitted from the bat itself and sound waves emitted from the prey.
In this study, we analyzed the pulse-duration, pulse-interval and peak-frequency of echolocation call in three species as Rhinolophus ferrumequinum, Pipistrellus abramus, and Myotis macrodactylus. The peak frequency and pulse duration for above mentioned species were 69 kHz, 47 kHz and 49 kHz and 69.39±8.76 ms, 4.95±0.77 ms and 3.09±0.48 ms for R. ferrumequinum, P. abramus and M. macrodactylus, respectively. The pulse intervals for R. ferrumequinum, P. abramus and M. macrodactylus were 103.61±9.05 ms, 67.59±3.47 ms and 66.35±4.96 ms, respectively. The pulse pattern of R. ferrumequinum was setting into a short FM call and linked to long CF call and went through the short FM call again. The pulse pattern of M. macrodactylus was comprised with serial short FM call and the CF call was not checked up in accordance with the spectrogram analysis. The long FM call and short CF call got join together for the P. abramus and the peak frequency was checked up at the pulse ending as CF call.