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1

Choosing the 'correct' bat detector - a reply

100%
Corben C., Fellers G. M.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
2

Temporal and spatial differences in the emission of calls by pipistrelle bats Pipistrellus pipistrellus and P. pygmaeus

75%
Downs N. C., Racey P. A.
Acta Theriologica
|
2007
|
tom 52
|
nr 1
The number of orientation, feeding and social calls emitted by pipistrelle batsPipistrellus pipistrellus Schreber, 1774 andP. pygmaeus Leach, 1825 was recorded throughout the night at eight different sites. Social calls were unaffected by weather variables, whereas orientation calls and feeding buzzes were both significantly affected by cloud and temperature conditions. The number of emissions of each call type was significantly different between sites, indicating that the bats used different sites for different activities. Significant positive correlations between all three combinations of call types occurred only during the middle of the night, corresponding with the nadir of flying insects. This suggests that bats were engaged in activities other than feeding at this time, such as territory protection or mate attraction.
3

Inventory of insectivorous bats on Mount Makiling, Philippines using echolocation call signatures and a new tunnel trap

63%
Sedlock J. L.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
The call signatures of sixteen Philippine insectivorous bat species are described, and used to inventory bats on Mount Makiling, Luzon. I compare these acoustic diversity data to those collected with mist nets, and a newly designed tunnel trap. The Rhinolophidae used calls with unique constant frequency components. Most vespertilionid calls could be identified to species based on call shape and minimum frequency, with the exception of those used by Pipistrellus spp. and Miniopterus schreibersii. The tunnel trap, mist nets, and the Anabat II detector recorded 22 species, including eight new records for Mount Makiling. Eighteen percent of the species were captured in mist nets, 68% were trapped, and 77% were detected acoustically. Twenty species were recorded either acoustically or with the trap. Two species were recorded exclusively with mist-nets, three with the tunnel trap, and four were only detected with the bat detector. Generally, bats possessing low intensity calls were not detected acoustically or captured in mist nets, but were captured in the tunnel trap. The tunnel trap captured most species flying below the canopy and the bat detector was effective for inventorying those flying above.
4

Hitting the wall: light affects the obstacle avoidance ability of free-flying little brown bats (Myotis lucifugus)

63%
McGuire L. P., Fenton M. B.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
5

Finding prey by associative learning in gleaning bats: experiments with a Natterer`s bat Myotis nattereri

63%
Siemers B. M.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
I show that a Natterer's bat (Myotis nattereri) was operantly conditioned to echo cues from a large object; in this case a round bowl full of mealworms. In a subsequent choice experiment the bat preferred the empty, round bowl over an unknown, quadratic bowl filled with prey. I suggest that the quick but transient learning of cues indicating prey rich habitat patches might be adaptive for bats hunting in cluttered environments, where they can often not directly detect prey using echolocation. Therefore, it might be an additional foraging strategy of some gleaning bats to search for specific structural cues indicating a high probability of prey being present.
6

Habitat preference and activity of the noctule bat Nyctalus noctula in the Bialowieza Primeval Forest

63%
Rachwald A.
Acta Theriologica
|
1992
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tom 37
|
nr 4
The echolocation calls of the noctule bat Nyctalus noctula {Schreber, 1774) were recorded at night, from June to August 1991, using a QMC S20Q bat detector, in 5 habitats (river, forest-meadow eeotone, village, coniferous forest, deciduous forest) of the Białowieża Primeval Forest (eastern Poland). Two main kinds of signals were identified: search calls and feeding buzzes. Acoustic activity was high over the rivers, in the forest-meadow eeotone and in small woodland villages. It was negligible inside the coniferous and deciduous forests. The differences among habiLats were especially evident in the case of feeding buzzes; no feeding was recorded inside deep deciduous forests. Two peaks in overnight activity were found, with maxima after sunset and before sunrise. Intraseasonal changes of activity were recorded; the highest activity was in July.
7

A new species of Kerivoula (Chiroptera: Vespertilionidae) from peninsular Malaysia

51%
Francis C. M., Kingston T., Zubaid A.
Acta Chiropterologica
|
2007
|
tom 09
|
nr 1
A new species of small Kerivoula is described from peninsular Malaysia. It is similar in size and form to Kerivoula hardwickii Miller 1898 or K. intermedia Hill and Francis 1984, but is distinguished by its distinctive colouration — dorsal fur has extensive black bases with shiny golden tips, ventral fur has dark grey bases with whitish-buff tips — as well as several characters of dentition and skull shape. Sequence analysis of the first 648 base pairs of cytochrome oxidase I gene (DNA barcode) indicates a divergence of at least 11% from all other species of Kerivoula, a difference comparable to that between other species of Kerivoula.
8

Echolocation behaviours of the Japanese pipistrelle bat Pipistrellus abramus during foraging flight

51%
Ma J., Jones G., Zhu G., Metzner W.
Acta Theriologica
|
2010
|
tom 55
|
nr 4
The acoustic structure of echolocation pulses emitted by Japanese pipistrellePipistrellus abramus (Temminck, 1840) bats during different phases of aerial hawking is described here for the first time. Behavioural observations of the foraging flight in conjunction with acoustical analysis of echolocation pulses indicated a flight path consisting of four distinct phases following the reconnaissance or search phase. Short (∼4.68 ms) and relatively broadband frequencymodulated (FM) pulses (∼23.55 kHz bandwidth) were emitted at a repetition rate of 15 Hz during presumed target approach. Presumed insect capture consisted of an early and a late buzz phase. Both buzz types were emitted at high repetition rates (111 Hz in early to 222 Hz in late) and consisted of very short, broadband FM pulses (1.26 ms in early to 0.3 ms in late). There was also a characteristically sharp drop in both the peak and terminal frequencies of each echolocation pulse during the transition from early to late buzz. No pulses were recorded during the final phase of foraging referred to as a “post-buzz pause”. Thus the foraging behaviour of this species consisted of five sequential phases involving four broad types of echolocation pulses.
9

Foraging and public information use in common pipistrelle bats (Pipistrellus pipistrellus): a field experiment

51%
Jonker M. N., Boer,de W. F., Kurvers R. H. J. M., Dekker J. J. A.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
Decision making by animals is likely to be influenced strongly by the behaviour of conspecifics. In this study we tested whether public information affected the foraging behaviour of common pipistrelles (Pipistrellus pipistrellus) by manipulating public information about the quality of foraging patches. Capture attempts during foraging are revealed by terminal buzzes, which are a potential source of public information about prey abundance for other foraging bats. We tested whether the estimation of food patch quality was affected by the number of terminal buzzes emitted by conspecifics. We conducted an experiment at 12 different locations in an urban habitat in the Netherlands. At each location we played back recordings of echolocation sounds of hunting bats with different terminal buzz rates and scored the bat activity. No significant differences between treatments were found. Our results do not support the hypothesis that bat activity increases in response to an increase in simulated terminal buzzes, suggesting that public information does not influence the choice of foraging patches in P. pipistrellus. We propose that P. pipistrellus does not use this kind of information because of either the high reliability of personal information or of the low collection costs associated with personal information.
10

A new cryptic species of Rhinolophus macrotis (Chiroptera: Rhinolophidae) from Jiangxi Province, China

51%
Sun K.-P., Feng J., Jiang T.-L., Ma J., Zhang Z.-Z., Jin L.-R.
Acta Chiropterologica
|
2008
|
tom 10
|
nr 1
A cryptic species of the big-eared horseshoe bat (Rhinolophus macrotis) was identified in Jiangxi Province, China, based on significant differences in echolocation frequencies and morphology. Consistent with the bimodal distribution of body sizes of R. macrotis specimens obtained from the same cave, we now consider this population to be comprised of two putative species; a large and a small form, with dominant echolocation call frequencies of 49 kHz and 65 kHz, respectively. Cytochrome b sequences of these two phonic forms diverged by 3.16–3.25%, a similar level of divergence to that between the large form and the outgroup, R. rex (3.33–3.77%). These differences strongly suggest that the two phonic forms are distinct species. We also found that the wing loading and aspect ratio of the small form was much lower than that of the large form, suggesting that the small form is capable of foraging in denser forest. Without dietary evidence, the ecological significance of the observed difference in echolocation call frequency between the two forms (16 kHz) remains unknown.
11

Field identification of the cryptic vespertilionid bats, Myotis lucifugus and M. yumanensis

51%
Weller T. J., Scott S. A., Rodhouse T. J., Ormsbee P. C., Zinck J. M.
Acta Chiropterologica
|
2007
|
tom 09
|
nr 1
Recent advances in molecular techniques have provided new tools for confirming species identities, however they can be expensive and results are not immediately available. Myotis lucificugus and M. yumanensis are morphologically cryptic species of bats sympatric in western North America that can be difficult to distinguish in the field. We evaluated a set of models that used morphological and echolocation call characters obtained in the field to predict species identity as determined by DNA analysis. We constructed models using data from 98 M. lucifugus and 100 M. yumanensis captured throughout the Pacific Northwest from which we had obtained high-quality, time-expansion recordings of their echolocation calls. The best model for distinguishing the species combined forearm length and characteristic frequency of echolocation calls and was able to identify 92% of M. lucifugus and 91% of M. yumanensis individuals, with ≥95% confidence. We evaluated the applicability of our model by testing it on additional datasets. Our model correctly classified 83% of M. lucifugus (n = 30) and 93% of M. yumanensis (n = 29) individuals captured in north-central Oregon, whose echolocation calls were recorded using a zero-crossings echolocation detection system. It also correctly classified 86% of M. lucifugus (n = 22) and 85% of M. yumanensis (n = 26) individuals, captured throughout our study area, for which only poor-quality time-expansion recordings of echolocation calls were obtained. Combining morphometrics with echolocation call characteristics may be a useful approach for distinguishing among pairs of cryptic species of bats in other areas.
12

A new species of Hipposideros (Chiroptera: Hipposideridae) from Sulawesi

51%
Bates P. J. J., Rossiter S. J., Suyanto A., Kingston T.
Acta Chiropterologica
|
2007
|
tom 09
|
nr 1
A new species of Hipposideros is described from South-East Sulawesi, Indonesia. Morphologically, it shows close affinities to Hipposideros papua but is substantially smaller. It is currently only known from Rawa Aopa Watumohai National Park, an area of semi-disturbed lowland rainforest, where it was the most common species of hipposiderid recorded. In this paper, data on its morphometrics and echolocation are included, along with a brief discussion of its ecology and reproductive biology.
13

Reliable automation of bat call identification for eastern New South Wales, Australia, using classification trees and AnaScheme software

51%
Adams M. D., Law B. S., Gibson M. S.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
Accurate and efficient identification of bat (Microchiroptera) echolocation calls has been hampered by poor knowledge of the intraspecific variability in calls (including regional variation), a lack of call parameters for use in separating species and the amount of time required to manually identify individual calls or call sequences. We constructed and tested automated bat call identification keys for three regions in New South Wales, Australia, using over 4,000 reference calls in ≈300 call sequences per region. We used the program AnaScheme to extract time, frequency and shape parameters from calls recorded with the Anabat system. Classification trees were built to separate species using these parameters and provided the decision rules for construction of the keys. An ‘Unknown’ category was included in the keys for sequences that could not be confidently identified to species. The reliability of the keys was tested automatically with AnaScheme, using independent sets of reference call sequences, and keys were refined before further testing on additional test sequences. Regional keys contained 18–19 species or included species groups. We report rates of sequence misidentification (accuracy) and correct identification (detection) relative to all sequences (including ‘unknowns’) used to test each version of a key. Refined versions of the keys were accurate, with total misidentification rates of 0.5–5.3% for the three regions. Additionally, total correct identifications for regions were 56–75% (> 50% for most species), an overall high rate of detection. When ‘unknowns’ were ignored, as is common in many published studies, correct identification for regions increased to 91–99%, rates which compare favourably to the most successful classifiers tested to date. The future use of AnaScheme for automated bat call identification is promising, especially for the large-scale temporal and spatial acoustic sampling to which Anabat is particularly suited.
14

Variability in echolocation calls of Pipistrellus pygmaeus [Chiroptera: Vespertilionidae] during search flight in different habitats

51%
Bartonicka T., Rehak Z.
Acta Theriologica
|
2005
|
tom 50
|
nr 2
The changes in echolocation behaviour and the structure of calls ofPipistrellus pygmaeus (Leach, 1825) were studied in different habitats of a floodplain forest in south-eastern Moravia (Czech Republic) in 2001–2002. Calls (403 observations) were recorded in different sites between April and mid June (before weaning) using a time expansion bat-detector. Three signals per individual were analysed and descriptive statistics of variables of calls were presented. Association of signal types with habitat structure (cluttered, side-cluttered, semi-cluttered and uncluttered space) was found in echolocation sequences of the search phase of flight.P. pygmaeus used mainly narrowband signals (bandwidths less than 15 kHz) in uncluttered space and wideband signals (more than 15 kHz) in cluttered space. Almost 6% of the inter pulse intervals of signals were twice (or more) longer than usual inter pulse intervals (mainly in uncluttered space). In general, temporal variables of signals reached higher values in uncluttered spaces (except for inter pulse interval) than in cluttered ones. On the contrary, spectral variables of signals reached lower values in uncluttered habitats in comparison with cluttered ones. In addition, the signals were less variable in open spaces while in cluttered and partly-cluttered habitats different and higher variability was found. We also studied the accuracy of identification of pipistrelles by call parameters and possible misidentifications in relation to habitat structure. Multivariate discriminant analyses were carried out on the time and frequency parameters of calls produced by pipistrelles.
15

A taxonomic review of Hipposideros halophyllus, with additional information on H. ater and H. cineraceus (Chiroptera: Hipposideridae) from Thailand and Myanmar

45%
Douangboubpha B., Bumrungsri S., Soisook P., Murray S. W., Puechmaille S. J., Satasook C., Si Si Hla Bu B., Harrison D. L., Bates P. J. J.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
Based on recent field surveys in Thailand, Myanmar, and northern peninsular Malaysia, this paper reviews the taxonomy, morphometric and acoustic characters, distribution and ecology of the little known, globally endangered species Hipposideros halophyllus. It lists nine new localities records, including the first from northern and peninsular Thailand, which represent a substantial increase in the species' known range; it confirms the record from northern peninsular Malaysia. In addition, it provides further information on two other small species of the Hipposideros bicolor group, H. ater and H. cineraceus.
16

Czy ptaki posługują się echolokacją?

44%
Byczkowska-Smyk W.
Wszechświat
|
1957
|
nr 03
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