Plasticity Of Echolocation Calls Of Two Kinds Of Bats In Different State And Habitat Complexity

In this paper, the plasticities of the echolocation calls of two constant-frequencybats, Rhinolophus sinicus and Hipposideros armiger, were studied in different statesand complex habitats. Meanwhile, the relationships were analyzed between the calls andtheir body shape and gender. The echolocation calls were recorded in different statesand complex habitats with Ultra Sound detector D980(Pettersson Elektronik AB). Weanalyzed the dominant frequency, maximum frequency, minimum frequency, pulseduration, pulse interval using Bat Sound Pro-Sound Analysis (Version:3.31), and madestatistical analysis by the SPSS13.0for Windows. The results were as followings:It showed that the echolocation calls of Rhinolophus sinicus in four states anddifferent complex habitat belong to the type of FM-CF-FM with2-5(mostly2-3)harmonic waves but the dominant frequency mainly concentrating in the CF section ofthe second harmonic one. Based on the comparison of echolocation calls in differentstates, the results indicated that the dominant frequency of Rhinolophus sinicus in flyingstate was the lowest with significant differences when compared with that in bag andholding state; the pulse duration in flying state was the longest with the significantdifferences when did in bag and resting state; and the pulse duration in bag state was theshortest with significant differences when did in holding and resting state. Based on thecomparison of echolocation calls in different complex habitats, the results present thatthere were significant difference in the dominant ferquency, pulse interval and pulseduration between one-tree and five-tree habitat, with the dominant ferquency in one-treehabitat being lower than in five-tree, and the pulse interval and pulse duration inone-tree doing longer than in five-tree. The body form (forearm length and weight) wasnot significantly difference between male and female individual, but the sex differencesof echolocation calls were significant in different states and complex habitat. Thedifferences in the dominant frequency and the highest frequency in four states anddifferent complex habitat were significant with the dominant frequency and the highestfrequency of female individuals were both higher than those of male.It showed that the echolocation calls of Hipposideros armiger in four states anddifferent habitat belong to the type of CF-FM with2-4consecutive pulses,2harmonicwaves but energy concentrating on the first one. harmonic waves but the dominantfrequency mainly concentrating in the CF section of the second harmonic one. Based onthe comparison of echolocation calls in different states, the results indicated that thedominant frequency of Hipposideros armiger in resting state was the highest withsignificant differences when compared with that in flying, bag and holding state; thepuls interval in holding state was the longest with significant differences when did withthat in flying and resting state; the puls duration in holding state was the longest with significant differences when did with that in flying, bag and resting state. Based on thecomparison of echolocation calls in different complex habitats, the results showed thatthe the dominant frequency in releasing state was the lowest, and that the dominantfrequency in five–tree habitat was the highest with significant differences whencompared with the other three complex habitats; the puls interval and puls duration inreleasing state were both the longest while those in five-tree were the shortest withsignificant differences when did with those in other three habitats. The body form(forearm length and weight) was significantly different between male and femaleindividual, with the forearm of female was shorter than that of male, and weight offemale was lighter than that of male. However, the sex difference of echolocation callswere not significant in four different states.In a word, the echolocation calls of both Rhinolophus sinicus and Hipposiderosarmiger varied with the state and the habitat complexity of the bats when those wererecorded, which meant the sound wave structure of echolocation calls of both of them isof plasticity and adaptability to habitat.