Intra-individual variation in the vocalized frequency of the Taiwanese leaf-nosed bat, Hipposideros terasensis, influenced by conspecific colony members.
We examined the intra-individual variation in resting frequency of the constant-frequency component of the second harmonic of the pulse (F (rest)) over 4 years in a laboratory colony of the Taiwanese leaf-nosed bat (Hipposideros terasensis). Patterns of change in F (rest) were observed when individuals were added to or removed from the colony so that we investigated whether F (rest) was affected by neighboring colony members. F (rest) of each bat continually showed a long-term gradual change throughout the year, and all bats in the colony increased or decreased their F (rest) in the same direction as a group non-seasonally. The greatest short-term changes were observed when new bats with a relatively low F (rest) joined the colony and F (rest) of new bats converged with those of the original colony members around 8 -16 days after their introduction. Conversely, a single individual showed sudden short-term decrease in F (rest) after its isolation from other colony members. These findings strongly indicate that F (rest) is flexible according to the presence of neighboring conspecific bats. We suggest that the audio-vocal feedback for conspecific pulses appears to be involved in the short- or long-term intra-individual variation in F (rest) other than factors previously thought such as age or season.
Department of Electrical Engineering, Doshisha University, 610-0321 Kyotanabe, Japan. ZXH03766@nifty.ne.jp
Shizuko
S
Hiryu
Koji
K
Katsura
Tsuyoshi
T
Nagato
Hideo
H
Yamazaki
Liang-Kong
LK
Lin
Yoshiaki
Y
Watanabe
Hiroshi
H
Riquimaroux
D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D002685:Chiroptera / Q000502:physiology*; D004455:Echolocation / Q000502:physiology*; D005426:Flight, Animal; D007398:Interpersonal Relations; D012934:Social Isolation; D013686:Telemetry; D014828:Vocalization, Animal / Q000502:physiology*