The Aversive Effect of Electromagnetic Radiation on Foraging Bats—A Possible Means of Discouraging Bats from Approaching Wind Turbines

Large numbers of bats are killed by collisions with wind turbines and there is at present no accepted method of reducing or preventing this mortality. Following our demonstration that bat activity is reduced in the vicinity of large air traffic control and weather radars, we tested the hypothesis that an electromagnetic signal from a small portable radar can act as a deterrent to foraging bats. From June to September 2007 bat activity was compared at 20 foraging sites in northeast Scotland during experimental trials (radar switched on) and control trials (no radar signal). Starting 45 minutes after sunset, bat activity was recorded for a period of 30 minutes during each trial and the order of trials were alternated between nights. From July to September 2008 aerial insects at 16 of these sites were sampled using two miniature light-suction traps. At each site one of the traps was exposed to a radar signal and the other functioned as a control. Bat activity and foraging effort per unit time were significantly reduced during experimental trials when the radar antenna was fixed to produce a unidirectional signal therefore maximising exposure of foraging bats to the radar beam. However, although bat activity was significantly reduced during such trials, the radar had no significant effect on the abundance of insects captured by the traps

A comparative study of prenatal development in Miniopterus schreibersii fuliginosus, Hipposideros armiger and H. pratti

<p>Abstract</p> <p>Background</p> <p>Bats comprise the second largest order of mammals. However, there are far fewer morphological studies of post-implantation embryonic development than early embryonic development in bats.</p> <p>Results</p> <p>We studied three species of bats (<it>Miniopterus schreibersii fuliginosus, Hipposideros armiger </it>and <it>H. pratti</it>), representing the two suborders Yangochiroptera and Yinpterochiroptera. Using an established embryonic staging system, we identified the embryonic stages for <it>M. schreibersii fuliginosus, H. armiger </it>and <it>H. pratti </it>and described the morphological changes in each species, including the development of the complex and distinctive nose-leaves in <it>H. armiger </it>and <it>H. pratti</it>. Finally, we compared embryonic and fetal morphology of the three species in the present study with five other species for which information is available.</p> <p>Conclusion</p> <p>As a whole, the organogenetic sequence of bat embryos is uniform and the embryos appear homoplastic before Stage 16. Morphological differentiation between species occurs mainly after embryonic Stage 16. Our study provides three new bat species for interspecific comparison of post-implantation embryonic development within the order Chiroptera and detailed data on the development of nose-leaves for bats in the superfamily Rhinolophoidea.</p

Reproductive ecology of wrinkle-lipped free-tailed bats Chaerephon plicatus (Buchannan, 1800) in Rrelation to Guano Production in Cambodia

Wildlife populations in Southeast Asia are subject to increasing pressure from climate change, habitat loss and human disturbance. Cave-roosting bats are particularly vulnerable to all three factors. Because of the ecological services they provide, it is important to assess specific vulnerabilities to inform their conservation management. We evaluated the reproductive phenology and body condition of Chaerephon plicatus for 14 months in 2015–2016 and quantified guano harvesting at the largest colony in Cambodia in 2011–2016. As in Thailand and Myanmar, two annual breeding cycles were recorded, characterized as continuous bimodal polyoestry, with parturition primarily occurring in April and October. Significant declines occurred in body condition between the late wet season and the late dry season, suggesting that bats experience increasing energetic stress as the dry season progresses. Annual guano harvests increased over the study period but could not be used as a proxy for monitoring population size due to the loss of unknown amounts during the wet season and unquantified movements of bats between C. plicatus colonies in the region. We recommend studies to determine the scale and drivers of such movements and creation of sustainable guano harvesting and population monitoring initiatives to ensure the conservation of C. plicatus colonies in Cambodia

Bats as bushmeat in Madagascar

Bats are eaten by people throughout Madagascar and although the larger species like Pteropus rufus, Eidolon dupreanum, Rousettus madagascariensis and Hipposideros commersoni are preferred, small insectivorous bats are also eaten. The national hunting season for bats is widely ignored and both unsuitable hunting practices and high offtake represent a serious threat to bat populations in some areas. Bat bushmeat may be an important source of protein for Malagasy people during periods of food shortage but in general there are few data on the socioeconomic and cultural importance of bats. Fruit bats produce a single offspring per year and are therefore susceptible to over-hunting. Nevertheless, large roosts offer the possibility of community managed harvests to secure the colony and provide a source of meat but further research is needed before this can be considered. Roost sites also present the best focus for conservation and greater effort is needed to control hunting using existing legislation and flexible community-based solutions that are sensitive to the local context. The threat of pathogen transfer from bats to people is of growing concern as more bat species are identified as vectors of emergent viral diseases.RÉSUMÉLes gens consomment des chauves-souris partout à Madagascar et s’ils préfèrent les plus grandes espèces comme Pteropus rufus, Eidolon dupreanum, Rousettus madagascariensis et Hipposideros commersoni, les petites chauves-souris insectivores sont également consommées. La période d’ouverture nationale de la chasse n’est généralement pas respectée et l’on assiste aussi bien à de mauvaises pratiques cynégétiques qu’à des prélèvements importants qui représentent une menace sérieuse pour les populations de chauves-souris dans certaines régions. Les chauves-souris peuvent constituer une source de protéines importante pour les populations villageoises pendant les périodes de soudure alimentaire mais en règle générale, il existe peu de données sur les valeurs socio-économiques ou culturelles des chauves - souris. Les chauves-souris frugivores ne produisent qu’un seul jeune par an, de sorte qu’elles sont sensibles à la pression de chasse bien que les grands dortoirs pourraient offrir l’occasion d’une exploitation gérée par la communauté pour assurer la sécurité des colonies et fournir une source de protéines mais de plus amples recherches sont nécessaires avant que cette alternative ne puisse être retenue. Les dortoirs constituent également les meilleures cibles des actions de protection de la nature et des efforts plus importants sont nécessaires pour contrôler la chasse en s’appuyant sur la législation nationale ainsi que sur des solutions locales plus souples et adaptées, basées sur la communauté. Les chauves-souris peuvent aussi transmettre des agents pathogènes et cette menace est une source d’inquiétude grandissante car de plus en plus d’espèces de chauves-souris ont été identifiées en tant que vecteurs de maladies virales émergentes.

A conservation assessment of Rousettus madagascariensis (Grandidier, 1929, Pteropodidae) roosts in eastern Madagascar

We visited four cave roosts of the near threatened, and endemic, fruit bat Rousettus madagascariensis over a five year period and found major threats to the bats from hunting and deforestation. The conservation of this species is particularly challenging because it is legally hunted inside its cave roosts. Although provisional protected area status was obtained for two sites with community support, hunting continued. R. madagascariensis roosts were associated with humid forest and the loss of vegetation around caves rendered them unsuitable for the bats at two abandoned sites. A few individual hunters can have a rapid and destructive impact on R. madagascariensis roosts and future initiatives in this area should involve working with hunters to develop realistic solutions to reduce hunting. These efforts need to be supported by habitat protection measures.  RÉSUMÉ L’espèce de chauve-souris frugivore Quasi Menacée Rousettus madagascariensis est endémique à Madagascar. Nous avons étudié quatre gîtes dans des grottes où cette espèce a établi des dortoirs diurnes en procédant à des visites multiples au cours d’une période de cinq ans et avons trouvé que la chasse et la déforestation constituaient les principales menaces pesant sur R. madagascariensis. La conservation de cette espèce est particulièrement difficile dans la mesure où la chasse dans ses dortoirs ou gîtes est permise. Bien que les deux sites abritant l’espèce bénéficient du statut de Nouvelle Aire Protégée avec le soutien de la communauté locale, la chasse ne cesse de s’intensifier. Les gîtes de R. madagascariensis sont associés à la forêt humide, de sorte que la disparition de la végétation arborée autour de deux de ces gîtes les a rendus impropres à héberger R. madagascariensis qui a fini par les abandonner. La disparition de la végétation arborée autour du gîte pourrait être à l’origine d’un changement de microclimat à l’intérieur de la grotte qui constitue le gîte diurne. Les activités de certains chasseurs peuvent aussi avoir un impact destructif rapide sur les gîtes de R. madagascariensis et des initiatives à mener conjointement avec les chasseurs sont nécessaires pour élaborer des mesures réalistes afin de réduire la chasse. De tels efforts doivent être étendus et appuyés par des mesures de protection de l'habitat car plusieurs autres gîtes pourraient exister dans les forêts du versant est de Madagascar et subir les mêmes pressions anthropiques. Des recherches récentes ont également montré que l’histoire naturelle de R. madagascariensis est étroitement liée à la forêt naturelle, de sorte que la perte de la biodiversité de la forêt naturelle malgache menace les plantes dont se nourrit cette espèce ainsi que l’équilibre de l’ensemble de l’écosystème dont elle dépend.

Feeding preference and seed dispersion by Roussetus madagascariensis Grandidier 1928 in North-western Madagascar

Experiments in a flight cage and observations in the field were carried out in North-western Madagascar to study the feeding preference of Rousettus madagascariensis (Family Pteropodidae) between an introduced fruit, jujube (Ziziphus jujuba, Family Rhamnaceae) and an endemic fig (Ficus sakalavarum, Family Moraceae) during the dry season, in May and June 2009. We also investigated quantitative aspects of seed dispersion by R. madagascariensis. Juvenile bats (13) fed intensively on F. sakalavarum, while adults (20) ate both fruit species but with a pronounced preference for unripe Z. jujube fruits. This preference for unripe (immature) fruit, the seeds of which are too large to swallow, suggested that R. madagascariensis does not affect seed dispersal in Z. jujuba. Almost half of the ingested seeds of F. sakalavarum were found in faeces of R. madagascariensis voided during the night in the flight cage, and the remainder was found in regurgitated ‘ejecta’ pellets. Rousettus madagascariensis is thought to be an effective seed disperser of F. sakalavarum, particularly for isolated trees or those in forest fragments where other frugivores are rareDes expériences dans une volière ou cage d'expérimentation et des observations in natura à proximité des arbres ont été réalisées dans la région nord-ouest de Madagascar pour étudier le choix de Rousettus madagascariensis (famille Pteropodidae) entre une espèce de fruit introduite le Jujubier (Ziziphus jujuba, famille Rhamnaceae) et une espèce de figuier endémique (Ficus sakalavarum, famille Moraceae) au cours de la saison sèche. L'aspect quantitatif de la dissémination des graines de cette dernière a également été étudié. Cette étude a été menée en mai et juin 2009. Rousettus madagascariensis utilise les deux espèces, mais la préférence entre les deux fruits varie en fonction de l'âge de l'animal. Les jeunes chauves-souris ont une préférence pour Ficus sakalavarum tandis que les adultes mangent aussi les jujubes qui ne sont généralement pas très mûrs et même si leur graine est trop volumineuse pour être avalée. Nous suggérons que cet animal n'assure pas la dissémination des graines de Z. jujuba. La dissémination des graines par cette espèce pourrait être moins favorable par rapport aux autres animaux qui avalent les graines. Presque la moitié des graines de F sakalavarum a été trouvée dans les fèces de R. madagascariensis laissés pendant la nuit dans la volière, le reste a été recraché sous forme de pelotes de régurgitation. Rousettus madagascariensis participe activement à la dissémination des graines de F. sakalavarum plus particulièrement celles de pieds isolés ou se trouvant dans des fragments d'habitats restreints où les autres animaux disséminateurs sont rares ou absents

Flying foxes create extensive seed shadows and enhance germination success of pioneer plant species in deforested Madagascan landscapes

<div><p>Seed dispersal plays a significant role in forest regeneration and maintenance. Flying foxes are often posited as effective long-distance seed dispersers due to their large home ranges and ability to disperse seeds when flying. We evaluate the importance of the Madagascan flying fox <i>Pteropus rufus</i> in the maintenance and regeneration of forests in one of the world’s priority conservation areas. We tested germination success of over 20,000 seeds from the figs <i>Ficus polita</i>, <i>F</i>. <i>grevei</i> and <i>F</i>. <i>lutea</i> extracted from bat faeces and ripe fruits under progressively more natural conditions, ranging from petri-dishes to outdoor environments. Seeds from all fig species showed increased germination success after passing through the bats’ digestive tracts. Outside, germination success in <i>F</i>. <i>polita</i> was highest in faecal seeds grown under semi-shaded conditions, and seeds that passed through bats showed increased seedling establishment success. We used data from feeding trials and GPS tracking to construct seed shadow maps to visualize seed dispersal patterns. The models use Gaussian probability density functions to predict the likelihood of defecation events occurring after feeding. In captivity, bats had short gut retention times (often < 30 mins), but were sometimes able to retain seeds for over 24h. In the wild, bats travelled 3–5 km within 24–280 min after feeding, when defecation of ingested seeds is very likely. They produced extensive seed shadows (11 bats potentially dispersing seeds over 58,000 ha over 45 total days of tracking) when feeding on figs within their large foraging areas and dispersed the seeds in habitats that were often partially shaded and hence would facilitate germination up to 20 km from the feeding tree. Because figs are important pioneer species, <i>P</i>. <i>rufus</i> is an important dispersal vector that makes a vital contribution to the regeneration and maintenance of highly fragmented forest patches in Madagascar.</p></div

Three flying fox (Pteropodidae: Pteropus rufus) roosts, three conservation challenges in southeastern Madagascar

We visited three roosts of the Madagascar flying fox Pteropus rufus in December 2005 in the Anosy Region. Colony size was 900 at Berenty Private Reserve, 412 at Amborabao and 54 at Sainte Luce, based on single counts at each site. Hunting at the roost is prohibited at Berenty but P. rufus is trapped at night in the area surrounding the reserve, where it feeds on sisal. At Amborabao, the bats roost in a sacred forest and hunting is forbidden. At Sainte Luce, the forest is highly degraded and the bats are hunted frequently, despite efforts to engage the local community in forest conservation. Questionnaires with people living near the roosts revealed the flying foxes were regarded as pests of litchis in Amborabao and Sainte Luce. Berenty is the only site where tourists are able to observe roosting P. rufus. The role of sacred forests and local taboos (fady) is very relevant for P. rufus conservation and might be the only practical mechanism in sites where legislation on hunting and land use is not being enforced. RÉSUMÉTrois gîtes de Pteropus rufus ont été visités dans la région Anosy en décembre 2005. La population était composée de 900 individus à Berenty, 412 à Amborabao et 54 à Sainte Luce, le comptage ayant été fait une seule fois dans chaque gîte. La chasse au dortoir est interdite à Berenty mais P. rufus est capturé la nuit, lorsque les individus se nourrissent dans les plantations de sisal environnantes. A Amborabao, le dortoir se trouve dans une forêt sacrée où la chasse est interdite. A Sainte Luce, la forêt est extrêmement dégradée et les chauves-souris sont chassées fréquemment malgré les efforts pour impliquer la communauté locale dans la conservation de la forêt. Les interviews avec les gens vivant près des dortoirs ont montré que les P. rufus sont considérés comme nuisibles car consommateurs de fruits de litchis à Amborabao et Sainte Luce. Berenty est le seul site où les touristes peuvent observer P. rufus au dortoir. Les forêts sacrées, les croyances locales et les tabous (fady) sont importants pour la conservation de P. rufus et pourraient être les seuls facteurs pour expliquer le respect des régulations cynégétiques et foncières

The movement ecology of the Mauritian flying fox (Pteropus niger):A long-term study using solar-powered GSM/GPS tags

Abstract Background Flying foxes (Chiroptera: Pteropodidae) are large bats that often roost in the sun, hence solar-powered GPS/GSM devices can track their movements over extended periods. The endemic Mauritian flying fox (Pteropus niger) has recently been subjected to large-scale culling because of perceived damage to commercial fruit, and a consequent reduction in numbers of > 50% since 2015 resulted in its IUCN Red List Status being up-listed to Endangered. Determining its movements will be important for management and conservation, for understanding potential responses to environmental change, and for understanding population admixture. Methods Twelve bats were tagged with solar-powered GPS/GSM devices in 2014–2016. Tags remained active for up to almost a year (maximum 359 days: average 139 days (males) and 93 days (females)), providing some of the longest-term data on the movement ecology of bats yet obtained. Eight bats were probably hunted illegally, highlighting the scale of unauthorised persecution. Results Males travelled on average 9 km each night, females 6 km. The nightly distance covered by adults of both sexes was higher in winter than in summer, though the opposite pattern occurred for immature males. These differences are probably related to seasonal changes in fruit availability (adults) and to dispersal by immature males. The maximum distance covered during one night was > 92 km. Home ranges of males averaged 74,633 ha, females 31,072 ha. Core foraging areas averaged 2222 ha for males, 1364 ha for females. Fifty roosts were identified, mainly in forest fragments. As the bats disperse seeds of native plants that form forest canopies, conservation of the bats will potentially maintain and enhance native forest cover, in turn providing roosting sites for the bats. Conclusions Solar-powered GSM tagging provides unprecedented potential for understanding the movement ecology of flying foxes. Mauritian flying foxes often move between the few remnant native forest fragments, which remain important for their conservation, and have potentially important roles in seed dispersal. Their nomadic movement fits with their panmictic genetic structure. Although their ability for long distance movements, sometimes over short timescales, permits rapid responses to local threats and environmental change, being restricted to Mauritius renders the bats extremely vulnerable to intense culling