Papers by Paulo Bobrowiec
The distribution patterns of animal species at local scales have been explained by direct influen... more The distribution patterns of animal species at local scales have been explained by direct influences of vegetation structure, topography, food distribution, and availability. However, these variables can also interact and operate indirectly on the distribution of species. Here, we examined the direct and indirect effects of food availability (fruits and insects), vegetation clutter, and elevation in structuring phyl-lostomid bat assemblages in a continuous terra firme forest in Central Amazonia. Bats were captured in 49 plots over 25-km² of continuous forest. We captured 1138 bats belonging to 52 species with 7056 net*hours of effort. Terrain elevation was the strongest predictor of species and guild compositions, and of bat abundance. However, changes in elevation were associated with changes in vegetation clutter , and availability of fruits and insects consumed by bats, which are likely to have had direct effects on bat assemblages. Frugivorous bat composition was more influenced by availability of food-providing plants, while gleaning-animalivore composition was more influenced by the structural complexity of the vegetation. Although probably not causal, terrain elevation may be a reliable predictor of bat-assemblage structure at local scales in other regions. In situations where it is not possible to collect local variables, terrain elevation can substitute other variables, such as vegetation structure, and availability of fruits and insects. Abstract in Portuguese is available with online material.
Biotropica, 2018
The distribution patterns of animal species at local scales have been explained by direct influen... more The distribution patterns of animal species at local scales have been explained by direct influences of vegetation structure, topography, food distribution, and availability. However, these variables can also interact and operate indirectly on the distribution of species. Here, we examined the direct and indirect effects of food availability (fruits and insects), vegetation clutter, and elevation in structuring phyl-lostomid bat assemblages in a continuous terra firme forest in Central Amazonia. Bats were captured in 49 plots over 25-km² of continuous forest. We captured 1138 bats belonging to 52 species with 7056 net*hours of effort. Terrain elevation was the strongest predictor of species and guild compositions, and of bat abundance. However, changes in elevation were associated with changes in vegetation clutter , and availability of fruits and insects consumed by bats, which are likely to have had direct effects on bat assemblages. Frugivorous bat composition was more influenced by availability of food-providing plants, while gleaning-animalivore composition was more influenced by the structural complexity of the vegetation. Although probably not causal, terrain elevation may be a reliable predictor of bat-assemblage structure at local scales in other regions. In situations where it is not possible to collect local variables, terrain elevation can substitute other variables, such as vegetation structure, and availability of fruits and insects. Abstract in Portuguese is available with online material.
Supporting Information S1. Restriction profiles of an amplified 359 bp fragment of Cytb generated... more Supporting Information S1. Restriction profiles of an amplified 359 bp fragment of Cytb generated from different mammal species potentially attacked by vampire bats in Brazilian Amazonia using five restriction enzymes. The Cytb sequences of each mammal species was obtained from the National Centre of Biotechnology Information (NCBI) database. The restriction profiles in bold indicate similarity with the profiles of the five target prey species. Order English common name Portuguese common name NCBI sequence ID Restriction enzymes Species Hae III Rsa I Bmg BI Taq I Xho I Cetartiodactyla Mazama americana Red brocket deer Veado
The deforestation is a major cause of forest degradation and habitat fragmentation in the Amazon.... more The deforestation is a major cause of forest degradation and habitat fragmentation in the Amazon. The destruction of habitat is the main threat to terrestrial mammal species. The BR-319 highway, abandoned since the year of 1988, is now proposed for reconstruction, threatening local biodiversity in Madeira-Purus interfluve. This interfluve is a region of high biodiversity and with heterogeneous ecosystems. We developed two scenarios of potential deforestation in the region of influence of Highway BR-319 with Dinamica-EGO software. The first scenario does not consider the reconstruction of the road (scenario without road) and the second considers the reconstruction of the highway in 2015 (scenario with road). Additionally we create ecological niche models to predict habitat suitability using Maxent software and derive the potential distribution of the fruit bat species Artibeus obscurus. To validate the deforestation model we used a modified fuzzy test and for the ecological niche model we used the receiver operating characteristic (ROC) curve. With the worst deforestation scenario (with the reconstruction of the highway) we calculate lost bat habitat. In the "without road" scenario the increase of deforestation is 5%, and in the "with road" scenario it is 11%. For this scenario, there is a 10% reduction in available habitat for the bat species.
1. Understanding how interspecific variation in functional traits influences species' capacity to... more 1. Understanding how interspecific variation in functional traits influences species' capacity to persist in fragments and use patches in fragmented landscapes is fundamental for the creation of effective conservation plans. This study uses phylogenetic comparative methods to investigate which functional traits of bat species are correlated with their vulnerability to fragmentation in a tropical landscape with low fragment-matrix contrast. 2. Bats were captured over two years in eight forest fragments, nine control sites in continuous forest, and in the secondary forest matrix at the Biological Dynamics of Forest Fragments Project, Central Amazon, Brazil. We tested the hypothesis that there is a significant relationship between species functional traits, environmental gradients (continuous forest and fragment interiors, edges and matrix) and patterns of species distribution using phylogenetic generalized least squares (PGLS) models, as well as a combination of RLQ and fourth-corner analyses. 3. Mobility, body mass, wing morphology, and trophic level were the most important traits linked to fragmentation sensitivity based on the PGLS analysis, while body mass and trophic level emerged as the best predictors in the fourth-corner analysis. These last two traits were correlated with the loss of continuous forest characteristics, such as high-stature trees and forest cover. 4. Many animalivorous bat species rarely persist in small fragments (<100 ha) and in the secondary forest matrix, reflecting strong effects of trait-mediated environmental filters that selectively benefit the smaller and phytophagous species. 5. Synthesis and applications. Functional traits of species and environmental variables jointly predict local variation in patterns of bat occupancy and abundance in fragmented tropical landscapes. To minimize local extinctions, we recommend increasing habitat availability and enhancing structural and functional connectivity at the landscape scale through the creation, restoration and maintenance of corridors and stepping stones. These measures should be coupled with improving matrix quality by promoting secondary forest regeneration and persistence to effectively reduce fragment-matrix contrast.
Vegetation clutter is a limiting factor for bats that forage near ground level, and may determine... more Vegetation clutter is a limiting factor for bats that forage near ground level, and may determine the distribution of species and guilds. However, many studies that evaluated the effects of vegetation clutter on bats have used qualitative descriptions rather than direct measurements of vegetation density. Moreover, few studies have evaluated the effect of vegetation clutter on a regional scale. Here, we evaluate the influence of the physical obstruction of vegetation on phyllostomid-bat assemblages along a 520 km transect in continuous Amazonian forest.We sampled bats using mist nets in eight localities during 80 nights (3840 net-hours) and estimated the ground-vegetation density with digital photographs. The total number of species, number of animalivorous species, total number of frugivorous species, number of understory frugivorous species, and abundance of canopy frugivorous bats were negatively associated with vegetation clutter. The bat assemblages showed a nested structure in relation to degree of clutter, with animalivorous and understory frugivorous bats distributed throughout the vegetation-clutter gradient, while canopy frugivores were restricted to sites with more open vegetation. The species distribution along the gradient of vegetation clutter was not closely associated with wing morphology, but aspect ratio and wing load differed between frugivores and animalivores. Vegetation structure plays an important role in structuring assemblages of the bats at the regional scale by increasing beta diversity between sites. Differences in foraging strategy and diet of the guilds seem to have contributed more to the spatial distribution of bats than the wing characteristics of the species alone.
Lasiurus egregius (Peters, 1870) is a rare Neotropical vespertilionid bat and virtually no data o... more Lasiurus egregius (Peters, 1870) is a rare Neotropical vespertilionid bat and virtually no data on its ecology and echolocation calls are currently available. We report the capture of four individuals in the Central Amazon, representing the first record for the region and a significant (> 800 km) expansion of the species’ known range. Echolocation calls, recorded for the first time under natural conditions, were 1.5–8 ms in duration, and characterized by high mean bandwidth (18 kHz) and a mean frequency of maximum energy of 30 kHz. Lasiurus egregius (Peters, 1870) é um morcego vespertilionídeo Neotropical cuja ecologia é praticamente desconhecida. Nós reportamos a captura de 4 indivíduos na Amazônia Central, representando o primeiro registo para a região e uma ampliação significativa (> 800 km) da distribuição conhecida para a espécie. Os pulsos de ecolocalização, gravados pela primeira vez em condições naturais, tiveram 1.5–8 ms de duração e foram caracterizados por uma alta frequência modulada (18 kHz) e frequência de máxima energia média de 30 kHz.
Morphological identification of prey fragments in vampire bat feces is impossible because of an e... more 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.
"Tem do grande e tem do pequeno. E também tem do que come lama", essas foram as palavras dos ribe... more "Tem do grande e tem do pequeno. E também tem do que come lama", essas foram as palavras dos ribeirinhos do alto rio Aripuanã que vivem no interior da floresta Amazônica quando indaguei, durante as noites de captura, se eles conheciam muitos tipos de morcegos naquela área. Infelizmente, sempre seguia o comentário de que todos aqueles morcegos só queriam sugar o sangue das pessoas enquanto dormiam. Durante as noites de conversa, dificilmente conseguia ouvir mais alguma informação sobre a diversidade de morcegos que rodeava aquelas pessoas todas as noites. Mesmo passando sua vida inteira na floresta, elas mal sabiam que na Amazônia existe a maior diversidade de morcegos (124 espécies) entre os biomas brasileiros, bem como o maior número de espécies endêmicas (11%) . Por mais que as pessoas conheçam os animais que vivem a sua volta, os morcegos continuam não incluídos entre os mais carismáticos.
In Amazonia, the assemblages of several taxa differ significantly between upland terra firme and ... more In Amazonia, the assemblages of several taxa differ significantly between upland terra firme and white-water flooded v arzea forests, but little is known about the diversity and distribution of bats in these two forest types. We compare the spatio-temporal patterns of bat assemblage composition and structure in adjacent terra firme and v arzea forests in the lower Purus River region of central Brazilian Amazonia. Bats were sampled using mist nets at five sites in each forest type during 40 nights (2400 net-hours). We captured 1069 bats representing 42 species and Phyllostomidae bats comprised 99.3 percent of all captures. The bat assemblages in v arzea and terra firme forests were significantly different, mainly due to a marked dissimilarity in species composition and in the number of captures during highwater season. In addition, bat assemblages within forest types differed significantly between seasons for both terra firme and v arzea. Frugivores dominated the bat assemblages in both forest types. Overall guild structure did not change between v arzea and terra firme or between seasons, but frugivore and animalivore abundance increased significantly in v arzea forest during the inundation. The difference in assemblage structure observed in the high-water season is probably caused by the annual v arzea flooding, which provides an effective barrier to the persistence of many understory bats. We also hypothesize that some bat species may undertake seasonal movements between forest types in response to fruit abundance, and our results further underline the importance of floodplain habitats for the conservation of species in the Amazon.
Succession in the Brazilian Amazon depends on prior land--use history. Abandoned clearcuts become... more Succession in the Brazilian Amazon depends on prior land--use history. Abandoned clearcuts become dominated by Cecropia trees and exhibit species replacements characteristic of natural succession in forest lightgaps. In contrast, abandoned pastures are dominated by Vismia trees that inhibit natural succession for a decade or more. Here we explore how advance regeneration and limited seed dispersal may contribute to the arrested succession in Vismia--dominated stands. Vegetation surveys showed that every Vismia stem in 3--8 year old Vismia stands originated as a re-sprout. In Cecropia stands, all tree species, including Vismia, originated mostly from seeds, after deforestation and abandonment. The 100% re-sprouts of Vismia in the abandoned pastures confirms that Vismia dominance results from re--sprouting following pasture fires. Seed rain in both Vismia and Cecropia dominated stands was limited almost exclusively to second growth species already reproducing in those stands, suggesting that the bats and birds foraging there were not bringing mature forest seeds into the second growth, but simply feeding and depositing local second growth species. As dispersal was similar in both stand types, dispersal differences cannot account for the ongoing dominance of Vismia relative to the ongoing successional transitions in Cecropia stands. Overall, advance regeneration in the form of Vismia re--sprouts is much more likely to be the driver of Vismia dominated succession than differential dispersal of mature forest seeds. In order to avoid extensive forest conversion into unproductive Vismia wastelands in the Amazon Basin, forestry permits for harvesting timber should include restrictions on subsequent anthropogenic degradation, such as conversion to pasture and prescribed burning. A regeneração florestal em áreas abandonadas na Amazônia depende, em primeiro lugar, na história de uso da terra. Áreas derrubadas seguidos de abandono são dominada por árvores de Cecropia e substituições apresentam espécies características de sucessão natural em clareiras. Em contraste, pastagens abandonadas são dominadas por árvores de Vismia que inibem a sucessão natural por uma década ou mais. Este estudo explora como a regeneração antecedência e a dispersão de sementes limitada, pode contribuir para a sucessão presada nas parcelas de Vismia. Levantamentos de vegetação mostraram que todos os troncos de Vismia nas parcelas de 3--8 anos de idade originaram--se como re-broto. Nas parcelas de Cecropia, todas as espécies, incluindo Vismia, originaram principalmente de sementes, após o desmatamento e abandono. Os 100% re--brotos de Vismia nas pastagens abandonadas confirma que a dominância de Vismia é o resultado de incêndios de pastagens. A chuva de sementes em ambos parcelas de Vismia e Cecropia era limitada quase exclusivamente às espécies da floresta secundária já reproduzindo nas parcelas, o que sugere que os morcegos e aves forrageando não traziam sementes da floresta madura para floresta secundária, mas simplesmente se alimentou e depositou espécies locais. Como a dispersão foi similar em ambos os tipos de dominância, as diferenças de dispersão não pode explicar a dominância de Vismia relativos às transições sucessionais em Cecropia. Em general, a regeneração avançada na forma de re--brotos é muito mais provável o condutor de dominância de Vismia que à dispersão de sementes florestais. A fim de evitar a conversão a florestas de Vismia, que são desertos improdutivos extensas na Bacia Amazônica, autorizações florestais para extração de madeira deve incluir restrições à degradação antrópica, tais como a conversão de pastagens e queimadas.
This study evaluated the potential of lowland tapirs as seed dispersers in the northern Brazilian... more 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.
Cyttarops alecto is a rare bat, poorly recorded along its distributional range. In this paper, we... more Cyttarops alecto is a rare bat, poorly recorded along its distributional range. In this paper, we report the fi rst record of C. alecto for the western Brazilian Amazon, provide information on distribution and morphological variation of the species along with taxonomic comments based on comparisons of our specimen with the previous information reported in the literature, and we reinterpret the precise type locality for the species.
Western Brazilian Amazonia is considered to be more bat species-rich than areas in other parts of... more Western Brazilian Amazonia is considered to be more bat species-rich than areas in other parts of the biome. However, the middle Madeira River region has been pointed out as a lacuna for mammal inventories, and information on its bat diversity is still scarce. I present here a bat fauna survey of the middle Madeira River region and its main tributary, the Aripuan ã River. Using mist nets [4626 meter net.hours (m.h)], I surveyed ten riverine village sites, four primary forest sites and one secondary forest site distributed along the margins of both rivers. In 22 nights during the dry and rainy seasons, 356 bats of 30 species and fi ve families were recorded. The bat species-richness was similar along both rivers, with 24 species in the Madeira sites and 23 in the Aripuan ã . Vampyriscus bidens and Mesophylla macconnelli were the most captured bats in the village sites along the Aripuan ã River, whereas all captures of Artibeus planirostris occurred along Madeira River villages. A new record for Vampyressa thyone in the Amazonas state is reported, approximately 500 km southeast of the nearest record.
Animal Conservation, Jan 1, 2010
The process of secondary succession on degraded lands in the Amazon depends on their land-use his... more 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.
We tested the removal effect on nectar production in four bat-pollinated cerrado flowers. We comp... more 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.
Uploads
Papers by Paulo Bobrowiec
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.
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.