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1

White-nose syndrome inflicts lasting injuries to the wings of little brown myotis (Myotis lucifugus)

100%
Reichard J. D., Kunz T. H.
Acta Chiropterologica
|
2009
|
tom 11
|
nr 2
White-nose syndrome (WNS) is an emerging disease causing massive mortality of hibernating bats in the northeastern United States. At hibernacula, bats affected with WNS typically exhibit growth of a white psychrophylic fungus (Geomyces destructans) on the nose, wings and ears; many individuals seem to prematurely die of starvation owing to depleted fat reserves. Conspicuous scarring and necrosis of the wings on WNS-affected bats that survive hibernation may have lasting consequences for survival and reproductive success during the active season. We monitored two maternity colonies of little brown myotis, Myotis lucifugus, in Massachusetts and New Hampshire from 14 May to 8 August 2008 to assess body conditions after expected exposure to WNS over the previous winter. We developed a 4-point wing damage index (WDI = 0 to 3) to assess the incidence and severity of wing damage in the months following emergence from hibernation. Severe wing damage was observed up to 4 June and moderate damage was observed through 9 July. Light wing damage was observed on both adult and juvenile bats throughout the study period, but was not exclusively attributed to WNS. The most severe wing damage was associated with a lower body mass index which may reflect reduced foraging success. Overall, reproductive rate was 85.1% in 2008; slightly lower than reported in previous studies. The incidence, timing, and geographic range of wing damage observed on little brown myotis in 2008 correspond to the occurrence of WNS at hibernacula. Monitoring wing conditions of affected and healthy bats will be important tool for assessing the spread of this disease and for establishing baseline data for unaffected bats. The simple scale we propose should be useful for monitoring wing conditions in any bat species.
2

Taxonomic history of the genus Anoura (Chiroptera: Phyllostomidae) with insights into the challenges of morphological species delimitation

100%
Jarrin-V P., Kunz T. H.
Acta Chiropterologica
|
2008
|
tom 10
|
nr 2
A surge in new species descriptions must be accompanied by an equal amount of healthy skepticism. Herein, we critique the current approach to species delimitation for the genus Anoura and assess the methodology used in these studies. It is not uncommon for studies committed to the delimitation of species to incur in a mismatch between their underlying epistemological perspective and the nature of species as real entities or ontological individuals. This is the reason why these studies must capitalize on the statistical paradigm to ascertain the degree of vagueness upon their particular approximation to real or purportedly real species. It is common for species to have fuzzy boundaries and numerous sources of variation. Furthermore, as multi-organismal entities, species deserve a more cautious action to their delimitation than purely verbal descriptions from the point of view of a single observer. We highlight the need for quantifiable methods that provide clear perspectives on the magnitude of overlap and variability within and among species. We argue that the delimitation of complex entities as evolutionary species must be framed under the paradigm of hypothesis testing and measurable and concrete estimates of character states. Quantitative hypothesis testing should be a requirement for the practice of systematics, taxonomy and species delimitation. Species are not mind constructs but complex ontological individuals awaiting discovery by means of precise statements of uncertainty.
3

Why does non-parental infanticide seem so rare in bats?

100%
Kunz T. H., Ebensperger L. A.
Acta Chiropterologica
|
1999
|
tom 01
|
nr 1
4

Nectar feeding behavior in the short-nosed fruit bat Cynopterus sphinx (Pteropodidae)

81%
Elangovan V., Marimuthu G., Kunz T. H.
Acta Chiropterologica
|
2000
|
tom 02
|
nr 1
Nectar feeding behavior of the short-nosed bat, Cynopterus sphinx, was observed under natural conditions in South India. Nectar production of 'steady-state' flowers of Musa x paradisiaca and 'big-bang' flowers of Bassia latifolia was quantified. Cynopterus sphinx typically foraged alone on flowers of M. x paradisiaca and as groups on B. latifolia, largely in response to the availability of these floral resources. Peak visits on flowers of M. x paradisiaca by C. sphinx occurred at 2000 h and on B. latifolia at 2100 h. Peak visits coincided with the maximum nectar production and sugar concentration of these floral resources. In addition to feeding on nectar early in the evening, C. sphinx acquired additional energy by feeding on carbohydrate-rich fruit. In return for these food resources, C. sphinx provides important pollination and seed-dispersal services to the plants that they visit nightly, and thus can profoundly influence the co-evolution of plants and bats.
5

The dorsal patch of males of the Curaçaoan long-nosed bat, Leptonycteris curasoae (Phyllostomidae: Glossophaginae) as a visual signal

81%
Munoz-Romo M., Burgos J. F., Kunz T. H.
Acta Chiropterologica
|
2011
|
tom 13
|
nr 1
The seasonal dorsal patch of males of the Curaçaoan long-nosed bat, Leptonycteris curasoae, which exhibits variability in size, shape, and chemical complexity, is a trait associated with courtship and mating in this species. This recently discovered structure develops exclusively during the mating season that occurs once a year between November and December in populations of L. curasoae from northern Venezuela. Although the dorsal patch that develops in males has unique chemical characteristics possibly involved in female attraction, we suggest that this trait also sends distinct visual cues regarding the health status of males. We evaluated the postulated association between dorsal patch shape (symmetry) and ectoparasite load (streblid batflies) in males of L. curasoae. To do so, we quantified the shape of dorsal patches on males to test the hypothesis that streblid load was related to this variable. Over 2,000 streblid batflies of two different species (Nycterophilia coxata and Trichobius sphaeronotus) were recovered from 130 individuals (x= 16 streblids/bat). Among these batflies, N. coxata was the most abundant species found on L. curasoae (2,042 individuals, 95.0% prevalence). Males with dorsal patches had significantly lower batfly loads when compared with males without dorsal patches and with females. Males with the most symmetrical dorsal patches also had the lowest batfly loads. Our results suggest that the odoriferous dorsal patches produced in males of L. curasoae also convey visual cues to female mates as signals of good health.
6

Distribution, relative abundance, and conservation status of the large flying fox, Pteropus vampyrus, in peninsular Malaysia: a preliminary assessment

81%
Mohd-Azlan J., Zubaid A., Kunz T. H.
Acta Chiropterologica
|
2001
|
tom 03
|
nr 2
An 11-month survey was undertaken to assess the relative abundance and distribution of the large flying fox, Pteropus vampyrus, in peninsular Malaysia. A total of 115 locations were visited based on sites that were identified from personal observations, published records, and information obtained from local villagers and wildlife and forestry personnel. Our survey suggests a severe decline in the abundance and distribution of P. vampyrus throughout peninsular Malaysia. At nearly half of all sites visited, there were no recent records or observations of this species. Several sites were used on a seasonal basis, others appeared to have been abandoned due to disturbance or habitat loss, and still others may have been extirpated by hunting. Most extant colonies are presumably located deep in isolated and inaccessible forests and in dense riparian vegetation such as mangrove and freshwater swamps. We suggest that unregulated hunting and habitat loss are the primary reasons for the decline in abundance of this species in peninsular Malaysia. Inadequacies in existing laws should be addressed and a public awareness program launched so that an effective conservation and management plan can be formulated to ensure the long-term survival of this ecologically important species.
7

Chemical composition of the substances from dorsal patches of males of the Curacaoan long-nosed bat, Leptonycteris curasoae (Phyllostomidae: Glossophaginae)

81%
Munoz-Romo M., Nielsen L. T., Nassar J. M., Kunz T. H.
Acta Chiropterologica
|
2012
|
tom 14
|
nr 1
In the absence of visual cues, chemical signals are especially important for nocturnal mammals such as bats, because they facilitate individual recognition, communication, and mate selection. In a recent study, it was reported that adult males of the Curaçaoan long-nosed bat, Leptonycteris curasoae, develop an odoriferous dorsal patch during the short mating season. It was postulated that dorsal patches signal health condition to females, and that females are preferentially attracted to the odor of males with dorsal patches. The chemical characterization of the dorsal patch is key to understanding its implications in chemical communication in a sexual context. In the present study, organic compounds collected from dorsal patches of males of L. curasoae from northwestern Venezuela were extracted using solid-phase micro-extraction (SPME) techniques and tentatively identified using GC-MS (Gas Chromatography-Mass Spectrometry). Nineteen compounds were present in 75% or more of the patches examined: 3-methyl-2-buten-1-thiol, acetic acid, 2′-aminoacetophenone, diacetyl, 2-pentanone, 2,3-dimethylpyrazine, 2-nonanone, acetamide, 2-undecanone, piperidinone, 4-methylquinazoline, 2,4-dimethylquinazoline, 3-methyl-2,5-pyrrolidinedione, 2-butanone, 2-methylfuran, 3-methyl-2-butenal, δ-valerolactone, 3-methyl-2-butenoic acid, and 2-methyl-2-butenoic acid. Although some of these compounds have been reported as important in female attraction among other male mammals during their respective breeding seasons, the actual function of these chemicals in L. curasoae remains to be determined. Some of these compounds have also been identified as natural insecticides, and this may be associated with lower ectoparasite loads reported on males with dorsal patches. These results, when considered along with previous observations, suggest that the dorsal patch in males of L. curasoae promotes the attraction of females during the mating season, and/or provides protection against ectoparasites.
8

Variation in serum 25-Hydroxyvitamin D in free-ranging New-World tropical bats

81%
Southworth L. O., Holick M. F., Chen T.-C., Kunz T. H.
Acta Chiropterologica
|
2009
|
tom 11
|
nr 2
Vitamin D (represented by D2 or D3) is considered essential for normal calcium homeostasis. It is either synthesized in the skin following ultraviolet-B irradiation of provitamin D3 (7-dehydrocholesterol), or ingested in the diet as vitamin D2 or vitamin D3. Most neotropical bats are nocturnal, roost in dark places, and consume diets that lack vitamin D and thus have no other known source of this important nutrient. A few species, namely fish-eating (piscivores) and blood-eating (sanguivores), however, have the potential to ingest large quantities of dietary vitamin D. In this study, blood serum collected from five nocturnal, neotropical bats (including three plant-visiting species, one fish-eating species and one blood-eating species), was analyzed using a competitive protein binding assay (CPBA) to determine concentrations of 25-hydroxyvitamin D [25(OH)D], the major circulating vitamin D metabolite. Cave-roosting (absence of sunlight), plant-visiting species (Artibeus jamaicensis, Brachyphylla cavernarum, and Monophyllus redmani) had a mean serum concentration of 25(OH)D between 7-15 ng/ml, values that are less than sufficient for humans. By contrast, cave-roosting, sanguivorous Desmodus rotundus and piscivorous Noctilio leporinus, species which have access to dietary vitamin D, had a mean serum concentration of 25(OH)D between 236-247 ng/ml, with high values to 400 ng/ml, the highest recorded for any vertebrate taxon. These findings support the hypothesis that circulating 25(OH)D concentrations in bats are strongly influenced by dietary habits.
9

Chemical composition of leaves consumed by the lesser dog-faced fruit bat, Cynopterus brachyotis, in peninsular Malaysia

71%
Rajamani L., Aminah A., Zubaid A., Tan K. H., Kunz T. H.
Acta Chiropterologica
|
1999
|
tom 01
|
nr 2
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