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White or clear ('whitish') wings are a distinct feature in about 30 species of tropical insectivorous bats (Mammalia: Chiroptera) belonging to three families (Emballonuridae, Molossidae, and Vespertilionidae). Such wings may provide camouflage against the sky at dusk and dawn, when bats commute to and from the roost and are vulnerable to aerial predation from birds. We tested this hypothesis by comparing the contrast of black, white, and transparent plastic models against the evening sky. Compared with normally dark wings, white and particularly transparent wings indeed reduce the contrast against the sky and may also prevent overheating in bats flying in daylight. Whitish wings could facilitate earlier evening emergence and later morning return, increasing access to crepuscular or diurnal insects as food. But whitish wings become maladaptive near artificial lights, where they are highly visible when illuminated against the dark sky. Pale but colored (not whitish) wings and reticulated patterns on translucent wings in some African and south Asian bats may be variations on the same theme, functional as camouflage against a lit background of vegetation and shades. Key words: aeroecology, bats, camouflage, Chiroptera, open air, overheating, predation, tropics. Des ailes blanches ou transparentes ([much less than] blanchatres [much greater than]) constituent un caractere distinctif chez quelque 30 especes de chauves-souris (mammiferes : chiropteres) insectivores tropicales appartenant a trois familles (emballonurides, molossides et vespertilionides). De telles ailes pourraient tenir lieu de camouflage sur le ciel au crepuscule et a l'aube, quand les chauves-souris se deplacent en provenance et en direction de leur dortoir et sont vulnerables a la predation aerienne par des oiseaux. Nous avons verifie cette hypothese en comparant le contraste de modeles en plastique noir, blanc et transparent avec le ciel du soir. Comparativement a des ailes normalement sombres, les ailes blanches et, en particulier, transparentes reduisent effectivement le contraste avec le ciel et pourraient aussi prevenir la surchauffe des chauves-souris volant a la lumiere du jour. Les ailes blanchatres pourraient faciliter l'emergence plus precoce en soiree et le retour plus tardif le matin, accroissant l'acces aux insectes crepusculaires ou diurnes comme source de nourriture. Les ailes blanchatres sont toutefois mesadaptees a proximite de lumiere artificielle, ou elles sont tres visibles dans le ciel obscur lorsqu'elles sont illuminees du bas. Des ailes pales, mais colorees (pas blanchatres) et des motifs reticules sur des ailes translucides chez certaines chauves-souris africaines et sud-asiatiques pourraient constituer des variations sur le meme theme, qui tiennent lieu de camouflage sur un arriere-plan illumine de vegetation et d'ombres. [Traduit par la Redaction] Mots-cles : aeroecologie, chauves-souris, camouflage, chiropteres, air libre, surchauffe, predation, tropiques., Introduction Animal coloration has long fascinated biologists, perhaps more so than other morphological features (e.g., Darwin 1859, 1871; Bates 1862; Wallace 1879; Poulton 1890; Cott 1940; Wickler 1968; Caro 2005). [...]

Sediments of the upper Hudson River, New York, USA, contain polychlorinated biphenyls (PCBs). Consequently, elevated levels of PCBs have been found in the tissues of bats and their insect prey along this region. However, it is not clear whether bat activity and foraging behaviour have been affected. To assess possible effects of PCBs on bat activity and foraging behaviour, we measured the activity of little brown bats (Myotis lucifugus (LeConte, 1831)) and hoary bats (Lasiurus cinereus (Palisot de Beauvois, 1796)) along the upper Hudson River, as well as abundance of insect prey at the same locations. We also measured foraging duration and distances travelled by radio-tagged M. lucifugus. We found that bat activity and insect abundance did not differ with PCB concentration. We did, however, find that foraging behaviour along the Hudson River differed from a control site. Specifically, M. lucifugus foraging along PCB-contaminated areas of the Hudson River travelled shorter distances from their roosts and spent less time foraging than bats at an uncontaminated site. Our results show that while bats roost and forage in areas historically exposed to PCBs, this exposure has not adversely affected bat activity, foraging behaviour, or abundance of insect prey. Key words: PCBs, Hudson River, Myotis lucifugus, little brown bat, Lasiurus cinereus, hoary bat, bat activity. Les sediments du cours superieur du fleuve Hudson (Etat de New York, Etats-Unis) contiennent des polychlorobiphenyles (PCB). Si des teneurs elevees de PCB ont du coup ete observees dans les tissus de chauves-souris et les insectes qui leur servent de proies dans cette region, il est toutefois difficile d'etablir si cela a eu une incidence sur l'activite et le comportement d'approvisionnement des chauves-souris. Afin d'evaluer les effets possibles des PCB sur l'activite et le comportement d'approvisionnement des chauves-souris, nous avons mesure l'activite de vespertilions bruns (Myotis lucifugus (LeConte, 1831)) et de chauves-souris cendrees (Lasiurus cinereus (Palisot de Beauvois, 1796)) le long du cours superieur du fleuve Hudson, ainsi que l'abondance d'insectes qui leur servent de proies aux memes emplacements. Nous avons egalement mesure la duree de l'approvisionnement et les distances parcourues par des vespertilions bruns munis de radio-emetteurs. Nous avons constate que l'activite des chauves-souris et l'abondance des insectes ne variaient pas en fonction de la concentration de PCB. Nous avons toutefois observe que le comportement d'approvisionnement le long du fleuve Hudson etait different de celui observe dans un site temoin. Plus precisement, les vespertilions bruns s'approvisionnant le long de zones contaminees aux PCB du fleuve Hudson s'eloignaient moins de leurs dortoirs et passaient moins de temps a s'approvisionner que les chauves-souris dans un site non contamine. Nos resultats montrent que, si les chauves-souris se reposent et s'approvisionnent dans des zones exposees par le passe aux PCB, cette exposition n'a pas eu d'effet negatif sur leur activite, leur comportement d'approvisionnement ou l'abondance des insectes qui leur servent de proies. [Traduit par la Redaction] Mots-cles: PCB, fleuve Hudson, Myotis lucifugus, vespertilion brun, Lasiurus cinereus, chauve-souris cendree, activite des chauves-souris., Introduction For over 40 years, polychlorinated biphenyls (PCBs) were used extensively as insulators and fire retardants in transformers and other industrial applications (Ross 2004). In 1976, the U.S. Congress banned [...]

Fat is an important fuel for bats to support high metabolic rates in extended periods of flight. The fatty acid composition of adipose stores could affect whole animal exercise performance, as fatty acids vary in rates of mobilization and oxidation. A key step in the fatty acid oxidation pathway is transporting fatty acids from the cytosol into mitochondria, mediated by the enzyme carnitine palmitoyl transferase (CPT). Therefore, understanding the substrate preference patterns of CPT in bats is important for interpreting the consequences of adipose fatty acid profiles. We measured CPT activity with eight different fatty acyl CoA substrates (16:0, 16:1ω7, 18:0, 18:1ω9, 18:2ω6, 18:3ω3, 20:4ω6, and 22:6ω3) in the pectoralis muscle of migrating and nonmigrating hoary bats (Lasiurus cinereus (Beauvois, 1796)). The pattern of substrate preference was similar to the patterns previously reported for birds and rats and was not affected by migration. Generally, activity increased with the number of double bonds and was higher with 16 carbon fatty acids compared with 18 carbon fatty acids. Given the observed substrate variation in CPT activity, there is no evidence to suggest that recently reported seasonal changes in the adipose fatty acid composition of migrating hoary bats would lead to increased lipid oxidation rate, and may instead be a consequence of seasonal shifts in diet. Key words: hoary bat, Lasiurus cinereus, carnitine palmitoyl transferase, carnitine acyl-transferase, lipid oxidation, fatty acid composition. Les graisses constituent un important carburant pour le maintien de vitesses metaboliques elevees chez les chauves- souris durant les periodes de vol prolongees. La composition en acides gras des stocks adipeux pourrait avoir une incidence sur la performance a l'exercice de tout l'animal puisque differents acides gras presentent differents taux de mobilisation et d'oxydation. Une des etapes cles de la voie d'oxydation des acides gras est le transport de ces derniers du cytosol vers l'interieur des mitochondries, dans lequel intervient l'enzyme carnitine palmitoyl-transferase (CPT). La comprehension des preferences en matiere de substrat de la CPT chez les chauves-souris est donc importante pour l'interpretation des consequences des profils d'acides gras des tissus adipeux. Nous avons mesure l'activite de la CPT pour huit substrats d'acyl-CoA d'acides gras (16:0, 16:1ω7, 18:0, 18:1ω9, 18:2ω6, 18:3ω3, 20:4ω6 et 22:6ω3) dans le muscle pectoral de chauves-souris cendrees (Lasiurus cinereus (Beauvois, 1796)) migratrices et non migratrices. Le motif de preference en matiere de substrat etait semblable aux motifs deja decrits pour des oiseaux et des rats et n'etait pas influence par la migration. En general, l'activite augmentait parallelement au nombre de liaisons doubles et etait plus grande pour les acides gras a 16 atomes de carbone que pour ceux a 18 atomes de carbone. Ala lumiere des variations de substrats observees dans l'activite de la CPT, rien n'indique que les variations saisonnieres recemment decrites de la composition des acides gras adipeux chez les chauves-souris cendrees migratrices se traduiraient par une augmentation du taux d'oxydation des lipides; ces variations seraient plutot une consequence de changements d'alimentation saisonniers. [Traduit par la Redaction] Mots-cles: chauve-souris cendree, Lasiurus cinereus, carnitine palmitoyl-transferase, carnitine acyl-transferase, oxydation des lipides, composition en acides gras., Introduction Migration physiology in bats has been little studied, although similar selective pressures on birds have likely lead to similar adaptations in fuel use (McGuire and Guglielmo 2009). Evidence from [...]

We studied spatial variation in echolocation call structure of the little brown bat (Myotis lucifugus (LeConte, 1831)) by analysing calls recorded from free-flying individuals at 1 site in Haida Gwaii, British Columbia, 1 site in Chautaqua, New York, and 20 sites along the Hudson River, New York. We controlled for factors that are often thought to lead to interspecific variation in echolocation calls (habitat, ontogeny, presence of conspecifics, recording techniques, ambient conditions), which allowed us to focus on the effect of spatial scale on call structure. As predicted, we found that at small scales (up to 1 km), there was significant geographic variation, likely owing to roost-specific signatures and group foraging activities. At intermediate scales (2-500 km), we found no differences in call structure, suggesting that populations within this area are part of a single hibernating and breeding population. Finally, echolocation call structure differed at the continental scale (>1000 km) likely because of little genetic exchange among sampled populations. Our results highlight the importance of considering the magnitude of spatial scale when examining variation in echolocation call structure. Key words: echolocation, geographic, spatial, variation, call structure, Myotis lucifugus, little brown bat. Nous avons etudie les variations spatiales de la structure des appels d'echolocation de la petite chauve-souris brune (Myotis lucifugus (LeConte, 1831)) en analysant les appels d'individus en vol libre enregistres dans 1 site de l'archipel Haida Gwaii (Colombie-Britannique), 1 site a Chautaqua (Etat de New York) et 20 sites le long du fleuve Hudson (Etat de New York). Comme nous avons pu controler les facteurs qui pourraient causer des variations interspecifiques des appels d'echolocation (habitat, ontogenie, presence de conspecifiques, techniques d'enregistrement, conditions ambiantes), il a ete possible d'examiner l'effet de l'echelle spatiale sur la structure des appels. Comme prevu, nous avons constate que, a petite echelle (jusqu'il 1 km), il y avait des variations geographiques significatives, vraisemblablement en raison de signatures particulieres des aires de repos et des activites d'alimentation en groupe. A des echelles intermediaires (de 2 a 500 km), nous n'avons note aucune variation dans la structure des appels, ce qui donne a penser que les populations dans cette region font partie d'une seule et meme population en ce qui concerne l'hibernation et la reproduction. Enfin, la structure des appels d'echolocation variait a l'echelle continentale (>1000 km), probablement en raison du peu d'echange genetique entre les populations echantillonnees. Nos resultats soulignent l'importance de tenir compte de la magnitude de l'echelle spatiale dans l'etude des variations de la structure des appels d'echolocation. [Traduit par la Redaction] Mots-cles: echolocation, geographique, spatial, variation, structure des appels, Myotis lucifugus, petite chauve-souris brune., Introduction Bats use echolocation to orient themselves in their environment, as well as to find and track prey (Griffin and Galambos 1941; Schnitzler et al. 2003; Fenton 2013). Phylogeny (Jones [...]

Endogenous markers are a valuable indicator of individual animal ecology, but data interpretation requires a detailed understanding of the timing of tissue formation. Fur is commonly used in bat research using endogenous markers, but the moulting cycles of most bat species are not well documented. In this review, we (i) describe methods of investigating bat moulting; (ii) summarize the current literature on bat moulting cycles, highlighting broad trends; (iii) discuss knowledge gaps; and (iv) make recommendations for optimal fur sampling protocols. Three characteristics may indicate moulting in bats: changing skin pigmentation; visible fur growth and colour changes; and endogenous markers. Most studies reported new fur growth once annually during summer-fall, although there were exceptions. The timing of new fur growth varies among species, sexes, and age classes. Individuals commonly experience asynchronous new fur growth, with dorsal fur growth occurring before ventral. Specific moult progressions vary among species. Knowledge gaps include moulting cycles in tropical species and in subadult and yearling bats; migration during new fur growth; and the timing of fur growth compared with shedding. We recommend that fur samples taken dorsally from adult males are the most likely to be representative of the bat's site of summer residency. Key words: bats, fur, moulting or molting cycle, endogenous markers, review. Si les marqueurs endogenes constituent un indicateur utile de l'ecologie individuelle des animaux, l'interpretation de ces donnees necessite une comprehension detaillee du moment de la formation des tissus. Bien que le poil soit couramment utilise dans la recherche sur les chauves-souris axee sur des marqueurs endogenes, les cycles de mue de la plupart des especes de chauves-souris ne sont pas bien documentes. Dans le present article, nous (i) decrivons des methodes permettant d'etudier la mue des chauves-souris, (ii) presentons une synthese des travaux existants sur les cycles de mue des chauves-souris pour en faire ressortir de grandes tendances, (iii) abordons les lacunes sur le plan des connaissances et (iv) formulons des recommandations relatives a des protocoles optimaux d'echantillonnage du poil. Trois caracteristiques pourraient indiquer qu'une chauve-souris est en mue, a savoir : un changement de la pigmentation de la peau, la croissance et des changements de couleur visibles des poils, ainsi que des marqueurs endogenes. Bien qu'il existe des exceptions, la plupart des etudes font etat d'une croissance de nouveaux poils une fois l'an, a l'ete-l'automne. Le moment de la croissance de nouveaux poils varie selon l'espece, le sexe et la classe d'age. Les individus presentent souvent une croissance non synchrone de nouveaux poils, la croissance des poils dorsaux etant plus hative que celle des poils ventraux. La progression de la mue varie egalement selon l'espece. Les lacunes sur le plan des connaissances touchent notamment aux cycles de mue des especes tropicales et des chauves-souris subadultes et d'un an, a la migration durant la croissance de nouveaux poils et au moment de la croissance de poils par rapport a celui de la perte de poils. Nous suggerons que les echantillons de poils dorsaux provenant de males adultes sont les plus susceptibles d'etre representatifs du lieu de residence estivale d'une chauve-souris. [Traduit par la Redaction] Mots-cles: chauves-souris, poils, mue ou cycle de mue, marqueurs endogenes, article de synthese., Introduction Analyses of endogenous biogeochemical markers in animal tissues are increasingly capable of informing our understanding of animal movement (e.g., Hobson and Wassenaar 2008; Kaimal et al. 2009; Sellick et [...]

Species-specific variations in wing morphology and echolocation call characteristics often define which of three structural habitat types (open, cluttered, and edge) different bat species most frequently and efficiently use for foraging. Although edges are recognized as important habitats for commuting and foraging bats, no study to date has examined the depth of edge influence (DEI), the extent of quantitative changes in activity with distance from an edge, for any bat species. We focused our study on five species: northern long-eared bat, Myotis septentrionalis (Trouessart, 1897); hoary bat, Lasiurus cinereus (Beauvois, 1796); little brown bat, Myotis lucifugus (LeConte, 1831); silver-haired bat, Lasionycteris noctivagans (LeConte, 1831); big brown bat, Eptesicus fuscus (Beauvois, 1796). We predicted DEI would vary with species-specific differences in wing morphology and echolocation call characteristics. From June to August in 2010 and 2011, we passively recorded echolocation calls three to four times per month at eight sites in eastern Ontario, Canada. We found that species' activity was highest at the edge, regardless of wing morphology and echolocation call characteristics. The DEI for all species was approximately 40 m into both forests and fields. Understanding the effects of DEI on bats will enable more effective acoustic monitoring in future studies and may provide crucial information for management decisions. Key words: edge effects, ecomorphology, habitat use, acoustic monitoring, bat activity, Vespertilionidae. Resume : Les variations interspecifiques de la morphologie des ailes et des caracteristiques des appels d'echolocation determinent dans bien des cas lequel de trois types structuraux d'habitat (ouvert, dense et de lisiere) differentes especes de chauves-souris utilisent plus frequemment et plus efficacement pour s'alimenter. Si les lisieres sont reconnues comme constituant d'importants habitats pour les chauves-souris en deplacement et en quete de nourriture, aucune etude a ce jour ne s'est penchee sur l'influence de la profondeur dans la lisiere (DEI), soit l'ampleur des modifications quantitatives de l'activite en fonction de la distance par rapport a la lisiere, pour des especes de chauve-souris. Notre etude s'est interessee a cinq especes : chauve-souris nordique, Myotis septentrionalis (Trouessart, 1897); chauve-souris cendree, Lasiurus cinereus (Beauvois, 1796); petite chauve-souris brune, Myotis lucifugus (LeConte, 1831); chauve-souris argentee, Lasionycteris noctivagans (LeConte, 1831); grande chauve-souris brune, Eptesicus fuscus (Beauvois, 1796). Nous avions predit que la DEI varierait en fonction de differences interspecifiques de la morphologie des ailes et des caracteristiques des appels d'echolocation. De juin a aout 2010 et 2011, nous avons enregistre de maniere passive, de trois a quatre fois par mois, les appels d'echolocation dans huit localites de l'est de l'Ontario (Canada). Nous avons observe que l'activite des especes etait a son plus fort a la lisiere, peu importe la morphologie des ailes et les caracteristiques des appels d'echolocation. La DEI pour toutes les especes etait d'environ de 40 m vers l'interieur tant des forets que des champs. La comprehension des effets de la DEI sur les chauves-souris se traduira par une plus grande efficacite de la surveillance acoustique dans les etudes futures et pourrait fournir des renseignements de grande importance pour les decisions touchant a l'amenagement. [Traduit par la Redaction] Mots-cles : effet de lisiere, ecomorphologie, utilisation de l'habitat, surveillance acoustique, activite des chauves- souris, vespertilionides., Introduction The spatial configuration of a landscape directly impacts the organisms living within it. The pattern of the landscape matrix affects species richness (Law et al. 1999; Holland and Fahrig [...]

Temporally precise vocal exchanges, termed 'antiphonal calling', might allow pair or group members to maintain social contact with greater efficiency than when calling independently. The white-winged vampire bat (Diaemus youngi (Jentink, 1893)) is a group-living species that produces social calls in antiphonal exchanges. Because white-winged vampire bats can use social calls to discriminate conspecifics, we suspect that one function of these vocal exchanges is to allow group members to know who is where. Here, we tested the prediction that antiphonal calling by groups of white-winged vampire bats increases when the spatial positions of conspecifics change. We recorded social calls from groups of four individually caged bats in total darkness, with each bat located in the corner of a 4 m x 4 m room. During test trials, we shifted the spatial positions of caged bats to new positions. During control trials, caged bats were displaced an equal distance but were returned to their original positions. We found that both the number of social calls and the proportion of antiphonal exchanges were greater during test trials than during control trials. These results suggest that white-winged vampire bats use antiphonal exchanges of social calls to monitor the spatial positions of conspecifics. Des echanges vocaux de grande precision temporelle, appeles << appels antiphoniques >>, peuvent permettre a des couples ou des membres d'un groupe de maintenir un contact social beaucoup plus efficacement que les appels individuels. Le vampire a ailes blanches (Diaemus youngi (Jentink, 1893)) est une espece qui vit en groupes et produit des appels sociaux lors echanges antiphoniques. Parce que les vampires a ailes blanches peuvent utiliser les appels sociaux pour reconnaitre les individus de meme espece, nous soupconnons qu'une des fonctions de ces echanges vocaux est de permettre aux membres du groupe de connaitre l'emplacement de chacun des individus. Nous verifions ici la prediction que les appels antiphoniques par des groupes de vampires a ailes blanches vont augmenter lorsque la position spatiale des individus de meme espece est modifiee. Nous avons enregistre les appels sociaux de groupes de quatre chauves-souris dans des cages individuelles en obscurite totale, chaque chauve-souris etant placee dans un coin d'une chambre de 4 m x 4 m. Durant les essais experimentaux, nous avons deplace les chauves-souris encagees vers de nouveaux emplacements. Durant les essais temoins, les chauves-souris ont ete deplacees d'une meme distance, mais retournees a leur position initiale. Tant le nombre d'appels sociaux que la proportion des echanges antiphoniques sont plus importants durant les essais experimentaux que durant les essais temoins. Ces resultats laissent croire que les vampires a ailes blanches utilisent les echanges antiphoniques d'appels sociaux pour connaitre et suivre les emplacements des individus de leur propre espece. [Traduit par la Redaction], Introduction Some bats roost, commute, or forage in groups with stable memberships, or even coordinate their flight activity (reviewed by Wilkinson 1995; see also Brown et al. 1983; Wilkinson and [...]

At temperate latitudes insectivorous bats face substantial nutritional demands prior to hibernation. As temperature decreases and availability of insect prey declines, bats must deposit nutrient stores for hibernation. The use of torpor allows bats to limit energy expenditures resulting in a net energy gain despite decreased energy intake. However, subadult bats have lower initial fat stores than adults and may have greater difficulty depositing sufficient nutrient stores to survive the winter. We used plasma metabolite analysis to determine the fueling performance of little brown bats (Myotis lucifugus (LeConte, 1831)) during swarming to see if subadults compensated for the increased challenges by increased feeding throughout the swarming period. During the period of our study (August and September), adult bats gained mass, while subadults lost mass. There was, however, no difference in nutrient intake of the age groups as indicated by plasma metabolite concentrations. The number of bats using torpor while roosting in the hibernaculum by day increased exponentially coincident with the onset of mating and a decrease in nutrient intake. The results are consistent with wild bats using torpor to minimize energy expenditure and compensate for lower nutrient intake. The difference in mass change for adults and subadults despite the same nutrient intake indicates that subadults incur greater energetic costs. Resume : Aux latitudes temperees, les chauves-souris insectivores font face a des besoins nutritifs importants avant 1'hibernation. An moment ou la temperature baisse et la disponibilite des insectes proies diminue, les chauves-souris doivent accumuler des reserves alimentaires en prevision de l'hibernation. L'utilisation de la torpeur permet aux chauves-souris de restreindre leurs depenses energetiques, ce qui a pour resultat un gain energetique net malgre 1'ingestion reduite d'energie. Cependant, les chauves-souris immatures possedent des reserves lipidiques initiales plus petites que celles des adultes et peuvent avoir plus de difficulte a accumuler suffisamment de reserves nutritives pour survivre a l'hiver. Une analyse des metabolites du plasma nous sert a determiner la performance du ravitaillement chez la petite chauve-souris brune (Myotis lucifugus (LeConte, 1831)) durant les essaimages afin de determiner si les immatures compensent ce defi additionnel en consommant plus de nourriture an cours de la periode d'essaimage. Durant notre periode d'etude (aout et septembre), les chauves-souris adultes ont fait des gains de masse, alors que les immatures ont connu des pertes de masse. Il n'y avait cependant pas de difference d'ingestion de nutriments entre les groupes d'age d'apres les concentrations des metabolites du plasma. Le nombre de chauves-souris qui utilisent la torpeur lorsqu'elles se perchent de jour dans le hibernacle augmente de facon exponentielle an moment du debut des accouplements et de la diminution de l'ingestion de nutriments. Nos resultats sont compatibles avec la proposition que les chauves-souris sauvages utilisent la torpeur pour minimiser leurs depenses d'energie et pour compenser la reduction de l'ingestion de nourriture. Les differences de changements de masse chez les adultes et les immatures malgre des ingestions semblables de nutriments indiquent que les immatures subissent des costs energetiques plus importants. [Traduit par la Redaction], Introduction At temperate latitudes many insectivorous species of bats hibernate for several months of cold winter when virtually no prey is available. Many species gather at hibernacula in large numbers [...]

Abstract: Eating behaviour can vary with age, experience, and gender, as well as food hardness. This variation can contribute to intraspecific dietary differences and may result in variable definitions of [...]

Bat detectors on helium-filled kite balloons revealed echolocating bats active at altitudes [less than or equal to] 600 m above the ground over Brachystegia woodland in the Sengwa Wildlife Research Area, Zimbabwe. Feeding buzzes indicated that bats were actively foraging to 600 m. At least seven species of bats were detected, including six molossids and one emballonurid. Key words: high-altitude bats, foraging, echolocation

Analysis of predator-prey response to measure the extent of death risks faced by bats from raptors reveals that bats form a regular meal to opportunistic raptors and that raptors attack bats through rapid hunting in areas where bats are numerous. Raised bat numbers in all colonies reduces raptor-attack risk of any individual but bats isolate themselves from large colonies despite increased attack risks.

In the field, Pipistrellus subflavus produces 5-ms-long, broadband, echolocation calls when flying in search of airborne prey. These calls typically have two strong harmonics, the first with energy between 35 and 19 kHz and the second with energy between 70 and 38 kHz. To an observer with two narrowband bat detectors, one tuned to 40 kHz and the other to 20 kHz, echolocation calls of P. subflavus are distinct from those of other sympatric species in the northern part of its geographic range.

Using radiotracking and direct observation we documented activity patterns and roost selection of Noctilio albiventris at the Estacion Experimental Enrique Jimenez Nunez near Canas, Costa Rica. Bats with radiotransmitters showed little consistency in their use of foraging areas. Observations of captive and free-flying animals suggested that time away from the roosts represented foraging time. Individual bats showed considerable variation in both foraging time and numbers of foraging bouts per night, but total time away from the roost usually averaged 120 min/night. Bats with radiotransmitters roosted in hollow trees and, although most used the same roosts repeatedly, some changed roosts during the study period.

Canadian Science Publishing, publisher of the Canadian Journal of Zoology, and the Editors of the Journal salute the Canadian Society of Zoologists as it celebrates its 50th anniversary year. We [...]

The new tools for studying bats, provided by the technological advances, will produce accurate and reliable data only when used appropriately. The objectives for the future conservation of bats are provided with scientific and technological studies.

Since 2001, the Canadian Journal of Zoology (CJZ) has published several review series on invertebrates entitled 'biology of neglected groups'. The CJZ also has published reviews on other important biological [...]

The present series of reviews on the Biology of neglected groups: Porifera (sponges) is the sixth and the last on the biology of invertebrates. We are pleased to report that [...]

We observed 18 individually banded red bats, Lasiurus borealis, foraging around streetlights to test our hypotheses that they were either foraging cooperatively or practising kleptoparasitism (theft of prey). In 80 of 238 attacks, bats reattacked the same moth (29% of these attacks involved >1 bat and 71% just 1 bat). Logistic regression showed that a bat's foraging-success rate was significantly positively affected by the number of attacks made on a moth (p < 0.05) and the type of attack (by a single bat versus >1 bat) (p < 0.05) but negatively affected by the length of time over which the moth was attacked (i.e., from the first to the second attack) (p < 0.05). Using a model we tested whether or not an eavesdropping L. borealis could be in a position to reattack a vulnerable (previously attacked) moth before the initial attacker and found that if an eavesdropper was within 30 m during the first attack it could always beat the first attacking bat to the vulnerable moth. The data and analysis support neither the cooperative-foraging nor the kleptoparasitism hypotheses, but rather show that a combination of timing of moth defensive behaviour and bat flight performance strongly influences the outcome of an attack. [ABSTRACT FROM AUTHOR]

ABSTRACT 1. Comparisons of original calls and their echoes allow echolocating microchiropteran bats to collect information about their surroundings. Echolocation calls are also a source of information for other animals. A spectacular example is the hearing-based defence of many species of insects that use echolocation calls to detect marauding bats. The role of echolocation calls remains unknown for bats that eat other bats. 2. Other eavesdroppers, biologists, regularly monitor echolocation calls to collect information about the distribution and patterns of habitat use of echolocating bats. People monitoring echolocation calls have discovered cryptic species of bats. 3. Vocal communication in bats involves social calls that serve only in communication, as well as echolocation calls that influence the behaviour of conspecifics and others. There is evidence of individual- and colony-specific social and echolocation calls. 4. The long age-spans of bats and the propensity of some species to roost in groups combine with conspicuousness of echolocation calls to set the stage for the discovery of more behavioural interactions mediated by individual-specific echolocation calls. In the echolocation of microchiropteran bats, signals can serve multiple functions, both for producers and listeners. [ABSTRACT FROM AUTHOR]

Presents a study which compared the measurable features of the echolocation calls of bats as recorded by two bat-detecting systems. Background information on the mammals; Materials and methods used; Findings and discussion.

Studies the effects of a small, rural garbage dump on local populations of Peromyscus leucopus and other small mammals in Ontario. Interactions between Peromyscus leucopus and Mus musculus; Animal behavior in simulated dump conditions; Species numerous in dumps as compared to other areas of natural habitat.

Studies the effects of roads on populations of small mammals in Ontario and Quebec in Canada. Numbers of mammals trapped at different road sites; Total mammal road crossings; Animal mortality on roads.