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1

Postnatal development of morphological features and vocalization in the pomona leaf-nosed bat Hipposideros pomona

100%
Jin L.-r., Lin A.-q., Sun K.-p., Liu Y., Feng J.
Acta Theriologica
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2011
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tom 56
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nr 1
Based on mark-recapture data, we studied the postnatal development of morphological features and vocalization of the pomona leaf-nosed bat (Hipposideros pomona). Morphological changes indicated that body mass and length of forearm followed a linear pattern of growth until 13 days of age at mean growth rates of 0.14 g/day and 1.08 mm/day, respectively, and thereafter, growth rates slowed. The length of the total epiphyseal gap of the fourth metacarpal–phalangeal joint showed a linear increase for up to 10 days, followed by a linear decrease until day 40 at a mean rate of 0.09 mm/day. Together, two equations permitted estimation of the age of H. pomona pups between 1 and 40 days. The logistic equation provided the best fit to the empirical curves for body mass and length of forearm. Studies of vocal development showed that the precursors of echolocation calls were not emitted until day 7 after birth. As the pups grew, the dominant frequency (DF) of isolation calls increased and number of harmonics (NH) decreased, whereas the duration remained relatively stable. The DF and BFM2 (the bandwidth of the terminal frequency-modulated sweep from the second harmonic) of the early echolocation calls increased; however, the NH and duration decreased.
2

Identification of bat species in Greece from their echolocation calls

84%
Papadatou E., Butlin R. K., Altringham J. D.
Acta Chiropterologica
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2008
|
tom 10
|
nr 1
Bats are the second most speciose order of mammals and are under significant threat throughout the world. Survey and monitoring of bats for conservation are severely hampered by the lack of a reliable and user-friendly method of identifying bats from their echolocation calls. We recorded and described time-expanded echolocation calls from 23 bat species in the National Park of Dadia-Lefkimi-Soufli, Greece. We compared the performance of quadratic and linear discriminant function analysis (DFA) of calls as a means of identifying species. Quadratic rather than linear DFA has been used by several researchers because of the violation of the method's basic assumption (homogeneity of variance-covariance matrices). However, when linear DFA was applied for the classification of recorded species in this study, correct classification rate was identical to the quadratic functions (82.4%) and linear models did not misclassify bats to the species with the greatest dispersion, the main problem caused by violation of the homogeneity assumption. The advantage of linear DFA is that it provides discriminant function coefficients. The linear combination of these coefficients and parameters from calls from unidentified bats can be used for species identification without access to the original data sets, an option not provided by quadratic analysis. When separate models were developed for Myotis species and for FM/QCF species, correct classification rates increased to 84.8% and 93.4%, respectively. DF coefficients thus provide a reliable identification tool, but intraspecific geographic variation must be taken into account.
3

Wing morphology, echolocation calls and emergence time of black-bearded tomb bats (Taphozous melanopogon, Emballonuridae) from southwest China

67%
Wei L., Han N., Zhang L., Helgen K. M., Parsons S., Zhou S., Zhang S.
Acta Chiropterologica
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2008
|
tom 10
|
nr 1
We studied the wing morphology, echolocation calls, diet and emergence time of the black-bearded tomb bat (Taphozous melanopogon) from May to October 2006 in Guangxi Province, southwest China. Taphozous melanopogon has wings with high aspect ratio, high loading and pointed wing-tip shape-characteristics associated with fast flight in open space. This species usually produces low-intensity, low frequency, and frequency-modulated (FM) calls usually containing up to four harmonics, with most energy in the second (or sometimes third) harmonic. The diet of this species consists mostly of Lepidoptera and Hemiptera. Timing of evening emergence is correlated with the time of sunset. This is the first study to describe the flight and echolocation behavior of this species in China, and opens the way for future studies of its biology.
4

Echolocation calls of the bats of Trinidad, West Indies: is guild membership reflected in echolocation signal design?

67%
Pio D. V., Clarke F. M., Mackie I., Racey P. A.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
Time-expanded echolocation calls were recorded from 29 species of Neotropical bats in lowland moist tropical forest in Trinidad, West Indies with three aims: (1) to describe the echolocation calls of the members of a diverse Neotropical bat community, especially members of the family Phyllostomidae, whose calls are not well documented (2) to investigate whether multivariate analysis of calls allows species and foraging guilds to be identified and (3) to evaluate the use of bat detectors in surveying the phyllostomids of Neotropical forests. The calls of 12 species of the family Phyllostomidae are described here for the first time and a total of 29 species, belonging to five families (Emballonuridae, Mormoopidae, Phyllostomidae, Molossidae and Vespertilionidae) were recorded. Quadratic discriminant function analysis (DFA) was used to obtain classification rates for each one of 11 individual species and for six guilds (based on diet, foraging mode and habitat) comprising 26 species. Overall classification rates were low compared to similar studies conducted in the Palaeotropics. We suggest that this may be due to a combination of ecological plasticity for certain species and a loose relationship between echolocation call shape, fine-grained resource partitioning and resource acquisition in phyllostomids.
5

A taxonomic review of Rhinolophus stheno and R. malayanus (Chiroptera: Rhinolophidae) from continental Southeast Asia: an evaluation of echolocation call frequency in discriminating between cryptic species

67%
Saisook P., Bumrungsri S., Satasook C., Thong V. D., Hla Bu S. S., Harrison D. L., Bates P. J.
Acta Chiropterologica
|
2008
|
tom 10
|
nr 2
The taxon Rhinolophus microglobosus is elevated to specific rank on the basis of clearly defined morphometric and acoustic characters which differentiate it from Rhinolophus stheno. It is recorded from Cambodia for the first time. Rhinolophus malayanus exhibits considerable geographical variation in echolocation calls, with apparently two phonic types: a northern population with lower frequency calls and a predominantly southern population with higher frequencies. However, this acoustic divergence is not reflected in any morphometric divergence, and the taxonomic status of the two phonic populations remains unclear. Discriminating characters of all three species are given, together with distribution data and short ecological summaries. The value of echolocation as an indicator of cryptic species and the zoogeographical implications of the study are briefly discussed.
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