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1.
An Acad Bras Cienc ; 94(1): e20191227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544864

RESUMO

The habitat loss is the main threat for many parrot species worldwide. However, the disturbed environments can influence the occurrence of the species positively or negatively, depending on its structure and potential use as an alternative environment. Therefore, this work aims to determine the relationship between land use types and the occurrence of the threatened Red-browed Amazon, identifying the land use types related to species' occurrence and the direction of these relationships. Seven land use types were significantly associated with the species' occurrence: Primary/Secondary Advanced/Medium Natural Forest, Secondary Natural Vegetation, Pasture, Outcrop/Bare Soil, Mangroves, Rivers and Urban Areas. We found that some land use types that are structurally different from the original environments (Pasture, Outcrop/Bare Soil and Urban Areas) positively affected the occurrence of the species. The relationship between intensity of occurrence and highly anthropized land use types, suggests a plasticity of the species in habitat use that may be contributing to the maintenance of Red-browed Amazon populations in highly disturbed habitats. Therefore, we proposed that the management of disturbed areas, along with usual conservation strategies (e.g., conservation of forest remnants, restoration of degraded areas), could contribute to Red-browed Amazon conservation.


Assuntos
Amazona , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Florestas , Solo
2.
Zoologia (Curitiba) ; 37: e37682, June 3, 2020. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-28521

RESUMO

The greater round-eared bat, Tonatia bidens (Spix, 1823), is a medium-sized phyllostomid bat distributed in the north of Argentina, Paraguay and Brazil. The diet and foraging patterns of this species are poorly known. We analyzed the composition of the diet of a population of T. bidens and how the temperature influences the consumption of vertebrates and invertebrates. To describe diet composition, we conducted weekly collections of food scrap from two monospecific night-perches. Data of temperature for the study period were taken from the meteorological station installed 300 m from the collection perches. The influence of temperature was evaluated using generalized linear models (GLMs) with negative binomial distribution. Tonatia bidens consumed 28 taxons (204 records), being at least 17 Artropods and 11 Passeriformes birds. Temperature explained a greater proportion of vertebrate abundance (R2 = 0.23) than invertebrate (R2 = 0.16) or to both pooled (R2 = 0.11). The relation with temperature was positive with invertebrates and negative with the vertebrates. The diet of the population of T. bidens comprised mainly invertebrates, which were the most frequent and diverse taxa. Data suggests that T. bidens has a diverse diet, with proportion of the items consumption varying temporally. Environmental factors, such as the temperature presented on this work, seems to be good proxies for the dietary traits of this species.(AU)


Assuntos
Animais , Quirópteros , Comportamento Animal , Dieta , Cadeia Alimentar , Estações do Ano , Brasil
3.
Zoologia (Curitiba, Impr.) ; 37: e37682, Feb. 7, 2020. map, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1504579

RESUMO

The greater round-eared bat, Tonatia bidens (Spix, 1823), is a medium-sized phyllostomid bat distributed in the north of Argentina, Paraguay and Brazil. The diet and foraging patterns of this species are poorly known. We analyzed the composition of the diet of a population of T. bidens and how the temperature influences the consumption of vertebrates and invertebrates. To describe diet composition, we conducted weekly collections of food scrap from two monospecific night-perches. Data of temperature for the study period were taken from the meteorological station installed 300 m from the collection perches. The influence of temperature was evaluated using generalized linear models (GLMs) with negative binomial distribution. Tonatia bidens consumed 28 taxons (204 records), being at least 17 Artropods and 11 Passeriformes birds. Temperature explained a greater proportion of vertebrate abundance (R2 = 0.23) than invertebrate (R2 = 0.16) or to both pooled (R2 = 0.11). The relation with temperature was positive with invertebrates and negative with the vertebrates. The diet of the population of T. bidens comprised mainly invertebrates, which were the most frequent and diverse taxa. Data suggests that T. bidens has a diverse diet, with proportion of the item’s consumption varying temporally. Environmental factors, such as the temperature presented on this work, seems to be good proxies for the dietary traits of this species.


Assuntos
Animais , Cadeia Alimentar , Comportamento Animal , Dieta , Quirópteros , Brasil , Estações do Ano
4.
Oecologia ; 189(4): 851-861, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30382388

RESUMO

Space and environment are fundamental in influencing the community structure. However, their relative influences vary according to species' biological characteristics. Here we test whether differences in life-history traits mainly linked to dispersal abilities influence bat, rodent and marsupial beta diversity along spatial and environmental gradients. We expect bat beta diversity to be weakly related with space in comparison to dispersal-limited rodents and marsupials. Using data from communities distributed along the Atlantic Forest of South America, we calculated the total beta diversity and its turnover and nestedness components for each group. We estimated the strength of correlation of beta diversity and its components along spatial and environmental gradients, comparing their importance within and between groups. Space had the higher influence on rodent and marsupial beta diversity. For bats, both gradients influenced similarly their community composition. Between taxa, the influence of these gradients did not differ for rodents and marsupials, while bats presented a stronger relationship with environment compared to non-volant small mammals. Also, all groups presented a similar influence of the spatial gradients on their community structure, despite their differences in dispersal abilities. Our results suggest that differences in biological characteristics partially influence the community structure of these mammals, with their responses along space likely reflecting similar biogeographical dynamics affecting their distribution. Overall, our results improve the understanding of the processes structuring these communities, highlighting the benefits of comparative analyses within a beta diversity perspective to better understand the influence of multiple processes on the community assembly along geographical gradients.


Assuntos
Quirópteros , Marsupiais , Animais , Biodiversidade , Florestas , Mamíferos , Roedores , América do Sul
5.
Ecology ; 99(2): 498, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399824

RESUMO

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

6.
Ecology ; 98(12): 3227, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28875505

RESUMO

Bats are the second most diverse mammal order and they provide vital ecosystem functions (e.g., pollination, seed dispersal, and nutrient flux in caves) and services (e.g., crop pest suppression). Bats are also important vectors of infectious diseases, harboring more than 100 different virus types. In the present study, we compiled information on bat communities from the Atlantic Forests of South America, a species-rich biome that is highly threatened by habitat loss and fragmentation. The ATLANTIC BATS data set comprises 135 quantitative studies carried out in 205 sites, which cover most vegetation types of the tropical and subtropical Atlantic Forest: dense ombrophilous forest, mixed ombrophilous forest, semideciduous forest, deciduous forest, savanna, steppe, and open ombrophilous forest. The data set includes information on more than 90,000 captures of 98 bat species of eight families. Species richness averaged 12.1 per site, with a median value of 10 species (ranging from 1 to 53 species). Six species occurred in more than 50% of the communities: Artibeus lituratus, Carollia perspicillata, Sturnira lilium, Artibeus fimbriatus, Glossophaga soricina, and Platyrrhinus lineatus. The number of captures divided by sampling effort, a proxy for abundance, varied from 0.000001 to 0.77 individuals·h-1 ·m-2 (0.04 ± 0.007 individuals·h-1 ·m-2 ). Our data set reveals a hyper-dominance of eight species that together that comprise 80% of all captures: Platyrrhinus lineatus (2.3%), Molossus molossus (2.8%), Artibeus obscurus (3.4%), Artibeus planirostris (5.2%), Artibeus fimbriatus (7%), Sturnira lilium (14.5%), Carollia perspicillata (15.6%), and Artibeus lituratus (29.2%).


Assuntos
Quirópteros/fisiologia , Florestas , Animais , Brasil , Ecossistema , América do Sul
7.
Acta amaz ; 47(1): 79-82, jan. -mar. 2017. ilus, map
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455330

RESUMO

Roosts are a key part of bat species' life stories. Information on roost use enables us to understand the biological processes underlying bat ecology and is crucial with regard to the natural-roost loss and environmental pressures related to habitat destruction that has been considered as a threat affecting bat conservation. The aim of this study was to collect new data on the diurnal artificial-roost use by bats in a landscape from the southern Amazon. We observed bat species roosting at an abandoned house in a highly fragmented ecotone between the Amazon and Cerrado biomes. We observed one Trachops cirrhosus individual roosting in physical contact with one Phyllostomus hastatus. One year later, we noticed a compositional change at this roost, in which we found a large colony of Pteronotus parnellii. These findings may shed light on the potential flexibility of the roosting requirements of these species in such landscapes. Moreover, this is one of the first records of the use of human constructions by P. parnelli in such fragmented landscapes, a bat species that until recently was thought of as being associated only with well-preserved natural roosts.


Abrigos desempenham um papel importante na história de vida dos morcegos. Informações sobre sua utilização possibilitam a compreensão dos processos biológicos associados à sua ecologia e são cruciais considerando que a perda de abrigos naturais e que as pressões ambientais relacionadas à descaracterização dos ecossistemas são ameaças para a conservação deste grupo. O objetivo desde estudo foi coletar novos dados sobre a utilização diurna de abrigos artificiais por espécies morcegos em uma região ao sul da Amazônia. Nós observamos espécies de morcegos abrigando uma casa abandonada em uma região ecotonal entre os biomas Amazônia e Cerrado. Neste local, observamos um indivíduo de Trachops cirrhosus em contato físico com um indivíduo de Phyllostomus hastatus. Após um ano, observamos uma mudança neste abrigo, no qual uma colônia de Pteronotus parnellii foi observada. Estes registros podem lançar luz sobre a possível plasticidade destas espécies com relação às suas necessidades para a utilização de abrigos nestas paisagens. O registro trazido aqui é um dos primeiros sobre a utilização de construções humanas por P. parnellii, uma espécie comumente associada a abrigos naturais e bem preservados.


Assuntos
Animais , Abrigo para Animais , Fenômenos Ecológicos e Ambientais , Quirópteros , Ecossistema Amazônico
8.
Acta amaz. ; 47(1): 79-82, jan.-mar. 2017. ilus, mapas
Artigo em Inglês | VETINDEX | ID: vti-688349

RESUMO

Roosts are a key part of bat species' life stories. Information on roost use enables us to understand the biological processes underlying bat ecology and is crucial with regard to the natural-roost loss and environmental pressures related to habitat destruction that has been considered as a threat affecting bat conservation. The aim of this study was to collect new data on the diurnal artificial-roost use by bats in a landscape from the southern Amazon. We observed bat species roosting at an abandoned house in a highly fragmented ecotone between the Amazon and Cerrado biomes. We observed one Trachops cirrhosus individual roosting in physical contact with one Phyllostomus hastatus. One year later, we noticed a compositional change at this roost, in which we found a large colony of Pteronotus parnellii. These findings may shed light on the potential flexibility of the roosting requirements of these species in such landscapes. Moreover, this is one of the first records of the use of human constructions by P. parnelli in such fragmented landscapes, a bat species that until recently was thought of as being associated only with well-preserved natural roosts.(AU)


Abrigos desempenham um papel importante na história de vida dos morcegos. Informações sobre sua utilização possibilitam a compreensão dos processos biológicos associados à sua ecologia e são cruciais considerando que a perda de abrigos naturais e que as pressões ambientais relacionadas à descaracterização dos ecossistemas são ameaças para a conservação deste grupo. O objetivo desde estudo foi coletar novos dados sobre a utilização diurna de abrigos artificiais por espécies morcegos em uma região ao sul da Amazônia. Nós observamos espécies de morcegos abrigando uma casa abandonada em uma região ecotonal entre os biomas Amazônia e Cerrado. Neste local, observamos um indivíduo de Trachops cirrhosus em contato físico com um indivíduo de Phyllostomus hastatus. Após um ano, observamos uma mudança neste abrigo, no qual uma colônia de Pteronotus parnellii foi observada. Estes registros podem lançar luz sobre a possível plasticidade destas espécies com relação às suas necessidades para a utilização de abrigos nestas paisagens. O registro trazido aqui é um dos primeiros sobre a utilização de construções humanas por P. parnellii, uma espécie comumente associada a abrigos naturais e bem preservados.(AU)


Assuntos
Animais , Quirópteros , Abrigo para Animais , Fenômenos Ecológicos e Ambientais , Ecossistema Amazônico
9.
Primates ; 58(1): 131-139, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27541307

RESUMO

The ovarian cycle in howler monkeys (genus Alouatta) has beean investigated through several biological parameters (ranging between 16.3 and 29.5 days); however, no data exist concerning the ovarian activity of the southern brown howler monkey (Alouatta guariba clamitans). This study aimed to describe the ovarian cycle of A. g. clamitans by profiling fecal progestin concentrations. Over 20 weeks, fecal samples of eight captive adult females of A. g. clamitans were collected. The collections were made at dawn, 5 days a week, and the samples were frozen immediately following collection. Next, they were dried, pulverized and hormonal metabolites were extracted to determine progestin concentrations by enzyme immunoassay. Of the 758 samples tested, the mean concentration of fecal progestins was 2866.40 ± 470.03 ng/g of dry feces, while the mean concentration at baseline was 814.47 ± 164.36 ng/g of dry feces. Among the eight females, one showed no ovarian cyclicity and three presented periods of probable absence of cyclicity and low progestin concentrations. A mean duration of 16 ± 0.52 days was observed for the 35 cycles studied. The interluteal phase lasted 4 ± 0.37 days on average, with a mean concentration of fecal progestins of 467.98 ± 29.12 ng/g of dry feces, while the luteal phase lasted 11 ± 0.50 days, with a mean concentration of 4283.27 ± 193.31 ng/g of dry feces. Besides describing the characteristics of the ovarian cycle, possible causes for the low concentrations of fecal progestins and periods of absence of cyclicity are also discussed.


Assuntos
Alouatta/fisiologia , Fezes/química , Ciclo Menstrual , Progestinas/metabolismo , Animais , Brasil , Feminino
10.
Zoologia (Curitiba) ; 32(1): 77-82, Jan.-Feb. 2015. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-28645

RESUMO

The microscopic characters of the hair can be used to indirectly identify species that are either uncommon or are difficult to see, for instance small Neotropical felids of the southern Brazilian Atlantic Forests. This widely used technique, which has not yet been standardized, involves the identification of hairs collected from feces. We tested the hypothesis that this tool is effective to identify four species of small Neotropical felids: Leopardus guttulus, Puma yagouaroundi, L. wiedii and L. pardalis. To accomplish that, we used measurements of the length, width and area of the cuticular scales in the guard hairs and calculated the relationship between width and length (quotient) for each species. A multiple discriminant analysis was conducted on the measurements and the percentage of correct identification was obtained. We found a high overlap in the quotients of these species, which indicates that this technique does not identify Neotropical felids accurately. This inefficiency was also confirmed by the multiple discriminant analysis, where only 74% correct identifications were obtained. Therefore we recommend that hair analysis is used only in combination with other sources of evidence, for instance molecular tools.(AU)


Assuntos
Animais , Felidae/anatomia & histologia , Felidae/classificação , Pelo Animal/ultraestrutura , Especificidade da Espécie
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