Prey preference of the common vampire bat (Desmodus rotundus, Chiroptera) using molecular analysis

Morphological identification of prey fragments in vampire bat feces is impossible because of an exclusively blood-based diet. Therefore, studies of their foraging ecology require innovative approaches. We investigated the diet of Desmodus rotundus using a PCR-restriction fragment length polymorphism (RFLP) molecular method by amplifying the cytochrome b mitochondrial gene (380 bp) from DNA fecal samples collected from captive bats fed with blood from chickens, cattle, pigs, dogs, and humans - the 5 most frequently attacked prey species in rural areas of the Brazilian Amazonia. The prey preference of the vampire bat was investigated in 18 riverine villages, where the availability of domestic animals to bats was quantified. Prey DNA amplified from fecal samples exhibited no visible signals of vampire bat DNA. A PCR - RFLP flowchart and a combination of 2 DNA restriction enzymes allowed the direct identification of prey to species level. The enzymes' restriction profile did not overlap with those of vampire bats or wild mammal and avian species. Chickens were the most attacked prey species (61.4% of the identifications, n = 27), but pigs were highly preferred in relation to prey availability. This suggests a preference for mammalian blood in D. rotundus diet, with chickens exploited as a secondary food source. No wild vertebrate species was identified in the fecal samples, indicating that vampire bats are selectively feeding on the blood of domesticated animals, probably because they are more predictable and easily accessed resources. © 2015 American Society of Mammalogists

Geographic variation in a South American clade of mormoopid bats, Pteronotus (Phyllodia), with description of a new species

The subgenus Phyllodia (genus Pteronotus) comprises 9 species ranging from the western coast of Mexico to central Brazil, including Greater and Lesser Antilles. Two of them, Pteronotus rubiginosus and Pteronotus sp. 1, form an endemic South American clade within Phyllodia and are reported in sympatry for several localities in Guyana, Suriname, French Guiana, and northern Brazil. We herein performed a comprehensive investigation to fully characterize the cranial variation and genetic intraspecific structuring within this clade. We also integrated genetic, morphological, and acoustic evidence to formally describe the species previously reported as Pteronotus sp. 1. Specimens of P. rubiginosus occurring in sympatry with the new species have a more distinctive cranial phenotype than those from allopatric areas, suggesting character displacement as a potential force promoting divergence by decreasing resource competition or reproductive interactions between them. Although the 2 species are sympatric in several localities, the divergence in their echolocation calls also may be promoting resource partitioning at the microhabitat level, with P. rubiginosus foraging in less cluttered areas and the new species restricted to more cluttered areas. © 2018 American Society of Mammalogists, www.mammalogy.org

Activity of the Insectivorous Bat Pteronotus parnellii Relative to Insect Resources and Vegetation Structure

Riparian areas often are assumed to be necessary sites for foraging by insectivorous bats because of high insect availability and ease of movement and echolocation in the forest. However, effects of vegetation clutter and insect availability on bat activity have not been compared between riparian and nonriparian areas. We used autonomous recorders to evaluate the effects of vegetation structure, insect mass, and assemblage composition on the activity of the aerial insectivorous bat Pteronotus parnellii along stream channels and nonriparian areas in a tropical rainforest in central Brazilian Amazonia. We quantified vegetation clutter using horizontal photographs, captured nocturnal insects with light traps, and recorded bat activity for 110 nights (1,320 h) in 22 sampling plots. Pteronotus parnellii was more active in sites with dense understory vegetation, which were more common away from riparian zones. Bat activity was related to insect availability (mass and composition), independent of the habitat type. Ability to detect insects on vegetation and avoid obstacles should not restrict the activity of P. parnellii in cluttered sites. This suggests that mass and species composition of insects had stronger influences on habitat use than did vegetation clutter. Pteronotus parnellii probably selects cluttered places as feeding sites due to the availability of higher quality prey. © 2015 American Society of Mammalogists

The role of parabiotic ants and environment on epiphyte composition and protection in ant gardens

Ant gardens (AGs) are a multi-partner specialized ant-plant interaction involving several ant and epiphyte species. Although studies on AGs have reported possible roles for some species in this system, there are unanswered questions regarding the process of epiphyte incorporation in the AGs and the role of less aggressive ant species in AG protection. In this study, we used AGs in the Brazilian Amazon forest formed by two parabiotic ant species to test a set of hypothesis regarding two main questions: 1) How is AG plant community composition affected by the surrounding environment? 2) Does Crematogaster levior play a role in the chemical detection of herbivory in the AGs? After identifying epiphytes occurring at AGs at the forest edge and in the interior, we found that ant gardens in each environment exhibited different compositions, and that plant species bearing oil or extrafloral nectar glands were more frequent in AGs located in the forest interior than in those at the forest edge. By performing experiments with volatile compounds emitted from injured epiphytes, we detected that only Camponotus femoratus was responsive, responding almost eight times faster in response to plant extracts than water treatments. Our results support the idea that environmental conditions affect ant preference for feeding resources provided by epiphytes and consequently shape the structure of the epiphyte community in AGs. On the other hand, the role of C. levior in AGs remains unknown, since it seems to play no direct or indirect role in AG protection

Removal effects on nectar production in bat-pollinated flowers of the Brazilian cerrado

We tested the removal effect on nectar production in four bat-pollinated cerrado flowers. We compared the amount of nectar after 7-12 removals with the accumulated nectar in non-manipulated flowers after 12 h. In all, but one species, removals increased volume by 1.5-4.6 times and sugar content by 1.6-4 times, which may affect flower visitation by bats, pollen flow, and reproduction. © 2011 The Author(s) Journal compilation © 2011 Association for Tropical Biology and Conservation

Effects of different secondary vegetation types on bat community composition in Central Amazonia, Brazil

The process of secondary succession on degraded lands in the Amazon depends on their land-use histories. In this scenario, little is known about how animal communities respond to different types of secondary vegetation in the region. We examined the effects of abandoned cattle pasture, Vismia- and Cecropia-dominated regrowth on the abundance of bat species and community composition in the Central Amazon, Brazil, based on 11 netting sites and on landscape characteristics. We captured 1444 bats, representing 26 species and two families (Phyllostomidae and Mormoopidae). Among the six most-captured Phyllostomidae bats, Sturnira lilium and Sturnira tildae had significantly higher capture rates in abandoned pasture, while Rhinophylla pumilio predominated in both Vismia- and Cecropia-dominated regrowth. An hybrid multidimensional scaling ordination revealed significant differences in the bat community among the three types of secondary vegetation. Phyllostominae bats were more common and richer in the less-disturbed areas of Cecropia-dominated regrowth, while Stenodermatinae species were more captured in abandoned pastures. Our results suggest that the type of secondary vegetation, together with its land-use history, affects bat community composition in the Central Amazon. The Phyllostominae subfamily (gleaning animalivores) was habitat selective and disappeared from areas experiencing constant disturbances. On the other hand, Stenodermatinae frugivorous bats often used and foraged in altered areas. We suggest that secondary vegetations in more-advanced successional stages can be used to augment the total area protected by forest conservation units. © 2009 The Authors. Journal compilation © 2009 The Zoological Society of London

Temperature, rainfall, and moonlight intensity effects on activity of tropical insectivorous bats

The extrinsic factors that most influence animal activity are weather and light conditions, which can be assessed at hourly, monthly, and even lunar-cycle timescales. We evaluated the responses of tropical aerial-insectivorous bats to temperature, rainfall, and moonlight intensity within and among nights. Temperature positively affected the activity of two species (Cormura brevirostris and Saccopteryx bilineata). Moonlight reduced Myotis riparius activity and increased the activity of Pteronotus rubiginosus and S. leptura. Rainfall can promote an irregular activity peak during the night compared to nights without rainfall, but the bats in our study were not active for a longer time after a rainfall event. Our findings indicate that moonlight and temperature are the variables with the highest impact on the activity of tropical insectivorous bat species and that some species are sensitive to small variations in rainfall among and within nights. © 2019 American Society of Mammalogists

Aerial insectivorous bat activity in relation to moonlight intensity

It is commonly assumed that aerial insectivorous bats in the tropics respond to moonlight intensity by decreasing their foraging activity during bright nights due either to an increase in predation risk, or to a reduction in insect availability. The effect of moonlight on bat activity can be measured both between nights and within a single night. However, few studies have simultaneously used both approaches, and most authors generally compare bat activity with lunar phases. Our main aim was to evaluate how moonlight influences aerial insectivorous bat activity at different time scales: between nights and within the same night. Activity of five bat species was measured using autonomous ultrasound recording stations and moonlight intensity percentages retrieved from the Moontool program nightly throughout a 53-day sampling period. Only one species (Myotis riparius) responded negatively to moonlight, while two species (Pteronotus parnellii and Saccopteryx leptura) increased their foraging activity in moonlight. For Cormura brevirostris and S. bilineata, moonlight intensity did not affect activity level. Bat activity was greater for all species at the beginning of the night, independent of the presence of the moon, indicating that foraging just after the sunset is adaptive. Thus, bat response to the effect of moonlight intensity is more apparent between nights than within a single night and may depend on species-specific traits, such as flight speed, flexibility in habitat use and body size. © 2016 Deutsche Gesellschaft für Säugetierkund

Seed germination from lowland tapir (Tapirus terrestris) fecal samples collected during the dry season in the northern Brazilian Amazon

This study evaluated the potential of lowland tapirs as seed dispersers in the northern Brazilian Amazon. The study analyzed the viability of seeds after passage through the gut. Fecal samples were collected from 6 different vegetation physiognomies in Viruá National Park during the dry season. The samples were then kept in a greenhouse for 16 months to allow the seeds to germinate. The seedling species were identified and classified according to the type of fruit, plant habit, seed size and type of ingestion. Of the 111 fecal samples, 94 (84.7%) had viable seeds of 75 species. Melastomataceae was the most frequent family with viable seeds in the fecal samples (69.1% of samples, N= 18 species). The data suggest that the importance of the lowland tapirs as dispersers is not restricted to the species consumed actively by frugivory but also extends to species accidentally consumed during browsing. The occurrence of both large and small viable seeds in the fecal samples as well as a number of large drupes, which probably cannot be transported via endozoochory by any other animal species, provide evidence of the ecological importance of lowland tapirs to the dynamics of the forest-campinarana vegetation mosaic in the region. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS