Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 231
Filtrar
1.
Iheringia, Sér. zool ; 112: e2022021, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1405119

Resumo

In this study, we observed that burrows of Rhinella dorbignyi (Duméril & Bibron, 1841) are distributed in a non-random manner in the habitat, suggesting a microhabitat selection for digging. This conclusion was based on a characterization of 36 burrows and surrounding micro-habitat. We established a 1 m x 1 m quadrat with the burrow in its central point (n=36) to measure the percentage (density) and the average heights of grasses, herbs, and shrubs. All measurements were repeated in two unused quadrats (without burrows) to evaluate the available microhabitat (n=72). The burrows are built in specific areas of the habitat with a higher percentage of grass, taller herbs, lower density of shrubs and low shaded sites than the founded at control sites. Based on three-dimensional models of the interior of the burrow (n=15), we observed that all of them were constructed with an elliptical opening that opens into a narrow channel perpendicular to the ground. Channels had a mean maximum diameter of 38 mm and a mean minimum diameter of 18 mm. The mean length of the burrows is 182 mm, and the mean volume is 95 mL.


Neste estudo, observamos que tocas de Rhinella dorbignyi (Duméril & Bibron, 1841) são distribuídas de uma forma não-aleatória no habitat, sugerindo que esta espécie seleciona sítios para cavá-las. Esta conclusão foi baseada em uma caracterização de 36 tocas e do micro-habitat que as cerca. Estabelecemos um quadrante de 1 m x 1 m com a toca como seu ponto central (n=36) para medir a porcentagem (densidade) e a altura média de gramíneas, plantas herbáceas e arbustos. Todas as medidas foram repetidas em dois quadrantes não utilizados (sem tocas), para avaliar o micro-habitat disponível ao anfíbio (n=72). As tocas são construídas em áreas específicas do habitat com maior porcentagem de gramíneas, ervas mais altas, menos arbustos presentes e pouca área sombreada. Baseado em modelos tridimensionais do interior das tocas (n=15), observamos que todas elas são construídas com uma abertura elíptica que se abre para um canal estreito, perpendicular ao chão. Os canais têm diâmetro máximo médio de 38 mm e diâmetro mínimo médio de 18 mm. O comprimento médio das tocas é de 182 mm, e o volume médio é de 95 mL.


Assuntos
Animais , Regulação da Temperatura Corporal , Bufonidae , Abrigo , Comportamento Animal , Brasil
2.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468711

Resumo

ABSTRACT Microhabitat factors associated with the habitat of barking deer (Muntiacus vaginalis) were examined and compared between summer and winter seasons. Habitat characteristics and preferred habitat were measured by locating direct and indirect signs. To quantify the habitat utilization of barking deer, each selected study site was sampled for floral diversity from 2015 to 2017. Quadrats were deployed along transect lines to determine seasonal distribution. Barking deer were not evenly distributed across vegetation types in the study area; they occurred more often in the broad-leaved forest than in Chir pine forest, at an elevational range of 550-850 m, in thick vegetation on steep slopes. The most preferred habitat included trees and shrubs with 30% and 69% cover, respectively. Barking deer avoided thicker tree cover, possibly as it hinders movement and escape from predators. No significant difference (2 = 6.37, df = 3, p = 0.19) in seasonal vegetation cover was recorded.


RESUMO Fatores de micro-hábitat associados ao hábitat do veado (Muntiacus vaginalis) foram examinados e comparados entre as estações de verão e inverno. As características do hábitat e o hábitat preferido foram medidos, localizando sinais diretos e indiretos. Para quantificar a utilização do hábitat de cervos-latidos, cada local de estudo selecionado foi amostrado para a diversidade floral de 2015 a 2017. Quadrats foram implantados ao longo de linhas de transecto para determinar a distribuição sazonal., Veados-latidos não foram distribuídos uniformemente pelos tipos de vegetação na área de estudo; ocorreram com mais frequência na floresta de folhas largas do que na floresta de pinheiros Chir, em uma faixa de elevação de 550-850 m, em vegetação densa, em encostas íngremes. O hábitat mais preferido incluía árvores e arbustos com 30% e 69% de cobertura, respectivamente. O veado-latido evitou uma cobertura de árvores mais espessa, possivelmente porque impede o movimento e a fuga de predadores. Nenhuma diferença significativa (2 = 6,37; df = 3; p = 0,19) na cobertura vegetal sazonal foi registrada.

3.
Pap. avulsos zool ; 62: e202262039, 2022. mapas, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1396450

Resumo

Natural resources are depleted in fragmented landscapes that have their vegetation also altered. As a result, the microhabitat diversity and the composition and distribution of local species are affected. In this study, we evaluated the small mammals' community diversity, composition and microhabitat selection in two Atlantic Forest fragments, in an ecotone area with the Pampa biome, southern Brazil. We recorded five rodents (Akodon montensis, Oligoryzomys nigripes, Sooretamys angouya, Juliomys pictipes and the exotic Rattus rattus) and one marsupial (Didelphis albiventris). Both fragments were dominated by the generalist rodent A. montensis. Akodon montensis and O. nigripes showed similar habitat preferences: ground covered by rocks and higher values of vegetation obstruction. Sooretamys angouya preferred places with higher abundance of trees. Fruit availability was important for A. montensis and D. albiventris, highlighting the importance of this food resource for local wildlife, and the potential role of these species as seed predators and dispersers. Small species richness, the presence of an exotic species and high dominance level suggest that the study area is highly degraded.(AU)


Assuntos
Animais , Roedores/fisiologia , Comportamento Alimentar/fisiologia , Marsupiais/fisiologia , Ecossistema , Pradaria
4.
Braz. j. biol ; 82: 1-13, 2022. tab, map, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468524

Resumo

Microhabitat factors associated with the habitat of barking deer (Muntiacus vaginalis) were examined and compared between summer and winter seasons. Habitat characteristics and preferred habitat were measured by locating direct and indirect signs. To quantify the habitat utilization of barking deer, each selected study site was sampled for floral diversity from 2015 to 2017. Quadrats were deployed along transect lines to determine seasonal distribution. Barking deer were not evenly distributed across vegetation types in the study area; they occurred more often in the broad-leaved forest than in Chir pine forest, at an elevational range of 550-850 m, in thick vegetation on steep slopes. The most preferred habitat included trees and shrubs with 30% and 69% cover, respectively. Barking deer avoided thicker tree cover, possibly as it hinders movement and escape from predators. No significant difference (χ2 = 6.37, df = 3, p = 0.19) in seasonal vegetation cover was recorded.


Fatores de micro-hábitat associados ao hábitat do veado (Muntiacus vaginalis) foram examinados e comparados entre as estações de verão e inverno. As características do hábitat e o hábitat preferido foram medidos, localizando sinais diretos e indiretos. Para quantificar a utilização do hábitat de cervos-latidos, cada local de estudo selecionado foi amostrado para a diversidade floral de 2015 a 2017. Quadrats foram implantados ao longo de linhas de transecto para determinar a distribuição sazonal., Veados-latidos não foram distribuídos uniformemente pelos tipos de vegetação na área de estudo; ocorreram com mais frequência na floresta de folhas largas do que na floresta de pinheiros Chir, em uma faixa de elevação de 550-850 m, em vegetação densa, em encostas íngremes. O hábitat mais preferido incluía árvores e arbustos com 30% e 69% de cobertura, respectivamente. O veado-latido evitou uma cobertura de árvores mais espessa, possivelmente porque impede o movimento e a fuga de predadores. Nenhuma diferença significativa (χ2 = 6,37; df = 3; p = 0,19) na cobertura vegetal sazonal foi registrada.


Assuntos
Animais , Cervo Muntjac , Comportamento , Ecossistema , Estações do Ano
5.
Braz. j. biol ; 82: e242334, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278515

Resumo

Microhabitat factors associated with the habitat of barking deer (Muntiacus vaginalis) were examined and compared between summer and winter seasons. Habitat characteristics and preferred habitat were measured by locating direct and indirect signs. To quantify the habitat utilization of barking deer, each selected study site was sampled for floral diversity from 2015 to 2017. Quadrats were deployed along transect lines to determine seasonal distribution. Barking deer were not evenly distributed across vegetation types in the study area; they occurred more often in the broad-leaved forest than in Chir pine forest, at an elevational range of 550-850 m, in thick vegetation on steep slopes. The most preferred habitat included trees and shrubs with 30% and 69% cover, respectively. Barking deer avoided thicker tree cover, possibly as it hinders movement and escape from predators. No significant difference (χ2 = 6.37, df = 3, p = 0.19) in seasonal vegetation cover was recorded.


Fatores de micro-hábitat associados ao hábitat do veado (Muntiacus vaginalis) foram examinados e comparados entre as estações de verão e inverno. As características do hábitat e o hábitat preferido foram medidos, localizando sinais diretos e indiretos. Para quantificar a utilização do hábitat de cervos-latidos, cada local de estudo selecionado foi amostrado para a diversidade floral de 2015 a 2017. Quadrats foram implantados ao longo de linhas de transecto para determinar a distribuição sazonal., Veados-latidos não foram distribuídos uniformemente pelos tipos de vegetação na área de estudo; ocorreram com mais frequência na floresta de folhas largas do que na floresta de pinheiros Chir, em uma faixa de elevação de 550-850 m, em vegetação densa, em encostas íngremes. O hábitat mais preferido incluía árvores e arbustos com 30% e 69% de cobertura, respectivamente. O veado-latido evitou uma cobertura de árvores mais espessa, possivelmente porque impede o movimento e a fuga de predadores. Nenhuma diferença significativa (χ2 = 6,37; df = 3; p = 0,19) na cobertura vegetal sazonal foi registrada.


Assuntos
Animais , Cervos , Cervo Muntjac , Paquistão , Estações do Ano , Ecossistema , Parques Recreativos
6.
Braz. J. Biol. ; 82: 1-13, 2022. tab, mapas, graf
Artigo em Inglês | VETINDEX | ID: vti-31607

Resumo

Microhabitat factors associated with the habitat of barking deer (Muntiacus vaginalis) were examined and compared between summer and winter seasons. Habitat characteristics and preferred habitat were measured by locating direct and indirect signs. To quantify the habitat utilization of barking deer, each selected study site was sampled for floral diversity from 2015 to 2017. Quadrats were deployed along transect lines to determine seasonal distribution. Barking deer were not evenly distributed across vegetation types in the study area; they occurred more often in the broad-leaved forest than in Chir pine forest, at an elevational range of 550-850 m, in thick vegetation on steep slopes. The most preferred habitat included trees and shrubs with 30% and 69% cover, respectively. Barking deer avoided thicker tree cover, possibly as it hinders movement and escape from predators. No significant difference (χ2 = 6.37, df = 3, p = 0.19) in seasonal vegetation cover was recorded.(AU)


Fatores de micro-hábitat associados ao hábitat do veado (Muntiacus vaginalis) foram examinados e comparados entre as estações de verão e inverno. As características do hábitat e o hábitat preferido foram medidos, localizando sinais diretos e indiretos. Para quantificar a utilização do hábitat de cervos-latidos, cada local de estudo selecionado foi amostrado para a diversidade floral de 2015 a 2017. Quadrats foram implantados ao longo de linhas de transecto para determinar a distribuição sazonal., Veados-latidos não foram distribuídos uniformemente pelos tipos de vegetação na área de estudo; ocorreram com mais frequência na floresta de folhas largas do que na floresta de pinheiros Chir, em uma faixa de elevação de 550-850 m, em vegetação densa, em encostas íngremes. O hábitat mais preferido incluía árvores e arbustos com 30% e 69% de cobertura, respectivamente. O veado-latido evitou uma cobertura de árvores mais espessa, possivelmente porque impede o movimento e a fuga de predadores. Nenhuma diferença significativa (χ2 = 6,37; df = 3; p = 0,19) na cobertura vegetal sazonal foi registrada.(AU)


Assuntos
Animais , Cervo Muntjac , Ecossistema , Estações do Ano , Comportamento
7.
Acta sci., Biol. sci ; 44: e58763, mar. 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1391174

Resumo

Anurans vary in body coloration and frequently exhibit color polymorphism, with selection by predation pressure favoring more cryptic animals. Spatial differentiation may also favor color polymorphism in some species, since cryptic morphotypes can use substrates that better match their coloration. Boana pulchella is a polymorphic species with green and brown morphotypes, but its polymorphism remains poorly understood. The aim of the present study was to determine the functionality of color polymorphism in B. pulchella as a defense strategy. Artificial green and brown clay models were placed in environments with green and brown background to determine if the two morphotypes of B. pulchella experience different frequencies of attacks. We expected that more conspicuous morphs are attacked more frequently. The attack rate, which suggests predation intent, on the models was 9.57%. The marks observed in the artificial models were left by both mammals and birds. The number of damaged models did not significantly differ between the different background environments. The results indicate that B. pulchella morphotypes are equally cryptic to predators in the studied environments. In conclusion, probably color polymorphism in B. pulchella is not operating as a defensive strategy, and other selective forces may be acting in the maintenance of color polymorphism in this species.(AU)


Assuntos
Animais , Masculino , Anuros/anatomia & histologia , Polimorfismo Genético/fisiologia , Morfogênese , Ecossistema , Modelos Anatômicos
8.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1483449

Resumo

ABSTRACT Climatic conditions and microhabitat characteristics, such as the substrate and type of vegetation, influence the choice of male anurans for calling sites that optimize their reproductive success. We evaluated the structure and selection of vocalization microhabitat of 17 individuals of Phyllomedusa distincta Lutz, 1950 and 25 of Boana leptolineata (Braun & Braun, 1977), in a subtropical forest in southern Brazil. We measure the height of the perch, the distance between the perch and the edge of the body of water and the structure of the microhabitat of quadrants used by individuals. The same attributes were measured in the quadrants available (but not used) by the individuals. We classified the microhabitats by visual estimate, assigning percentages of coverage for each quadrant by herbaceous, shrub, tree and wetland vegetation. We observed that both species selected their microhabitat, since the characteristics of the quadrants occupied by the individuals were different from those available. Phyllomedusa distincta was more associated with heterogeneous microhabitats, while B. leptolineata occurred in environments with greater coverage of tree strata. Additionally, we observed that both species used shrubs more frequently as a perch site. The selection of these microhabitat characteristics must be associated with strategies to optimize the use of the reproductive habitat, based on the morphological and behavioral characteristics of the species. Finally, it is possible to infer that the differences observed in the microhabitat structure selected by the species can facilitate the coexistence of both in the context of the heterogeneity of the environment.


RESUMO Seleção e uso de sítios de vocalização por Boana leptolineata e Phyllomedusa distincta durante o período reprodutivoAs condições climáticas e as características de micro-habitat, como o substrato e o tipo de vegetação, influenciam a escolha de anuros machos por sítios de vocalização que otimizem seu sucesso reprodutivo. Avaliamos a estrutura e a seleção de micro-habitat de vocalização de 17 indivíduos de Phyllomedusa distincta Lutz, 1950 e 25 de Boana leptolineata (Braun & Braun, 1977), em uma floresta subtropical no sul do Brasil. Medimos a altura do poleiro, a distância do poleiro até a margem do corpo dágua e a estrutura do micro-habitat de quadrantes utilizados pelos indivíduos. Os mesmos atributos foram mensurados nos quadrantes disponíveis (mas não utilizados) pelos indivíduos. Classificamos os micro-habitats por estimativa visual, atribuindo-se porcentagens de cobertura de cada quadrante por vegetação herbácea, arbustiva, arbórea e de área alagada. Observamos que ambas as espécies selecionaram seu micro-habitat, uma vez que as características dos quadrantes ocupados pelos indivíduos foram distintas daquelas disponíveis. Phyllomedusa distincta esteve mais associada a micro-habitats heterogêneos, enquanto B. leptolineata ocorreu em ambientes com maior cobertura de estrato arbóreo. Adicionalmente, observamos que ambas as espécies utilizaram mais frequentemente arbustos como local do poleiro. A seleção destas características de micro-habitat deve estar associada a estratégias para otimização do uso do habitat reprodutivo, baseadas em características morfológicas e comportamentais das espécies. Por fim, é possível inferir que as diferenças observadas na estrutura de micro-habitat selecionadas pelas espécies podem facilitar a coexistência de ambas no contexto da heterogeneidade do ambiente.

9.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487432

Resumo

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animals presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and trees diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

10.
Pap. avulsos zool ; 61: e20216118, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1287477

Resumo

Abstract Understanding how different environmental factors influence species occurrence is a key issue to address the study of natural populations. However, there is a lack of knowledge on how local traits influence the microhabitat use of tropical arboreal lizards. Here, we investigated the microhabitat selection of the poorly known lizard Tropidurus lagunablanca (Squamata: Tropiduridae) and evaluated how environmental microhabitat features influence animal's presence. We used a Resource Selection Function approach, in a case/control design where we analyzed the effect of substrate temperature and tree's diameter at breast height (DBH) in the probability of presence of lizards using mixed Conditional Logistic Regression. We found that T. lagunablanca uses trees with DBH from 0.40 m to 4 m and substrate temperatures ranging from 25.9°C to 42°C. Moreover, we showed that thickness of the trees and substrate temperatures significantly increased the probability of presence of T. lagunablanca individuals, being the probability of presence higher than 50% for trees up to 1.5 m DBH and temperature of substrate up to 37.5°C. Our study probed that T. lagunablanca individuals choose trees non-randomly, selecting thicker and warmer tree trunks. This information advances the knowledge of the spatial ecology of Neotropical arboreal lizards and is relevant for conservation, putting an emphasis on preserving native vegetation in the Pantanal.

11.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1483457

Resumo

ABSTRACT This work aimed to assess the diversity and microhabitat use of benthic invertebrates in an urban forest stream in southeastern Brazilian region. The invertebrates were sampled in a headwater stream, located at the Tijuca Forest, Rio de Janeiro. Three types of microhabitats were sampled (litter, sand and stone) using a Surber sampler. Specimens were identified to the family-level and rarefaction curves were constructed for the total sampling and for each type of microhabitat. Community structure indices (abundance, taxonomic richness, diversity, and dominance) were calculated for each microhabitat. Differences among indices were tested through a repeated measure ANOVA, and differences among microhabitats composition through a PerMANOVA. A total of 9,800 specimens were registered in which Chironomidae was the most abundant. The rarefaction curves did not reach the asymptote. Community structure indices exhibited differences (RM ANOVA; p 0.001), as well as microhabitats composition (PerMANOVA; p 0.001). Abundance and taxonomic richness were the highest in litter, diversity was higher both in litter and stone, and sand had the highest dominance. Results highlighted that the variety of microhabitats may enhance local diversity and that the differences in resources availability of each type of microhabitat determine the distribution of these invertebrates.


RESUMO Diversidade e uso de microhabitat de invertebrados bentônicos de um riacho de floresta urbana (Sudeste do Brasil). Este trabalho teve como objetivo avaliar a diversidade e o uso de microhabitat de invertebrados bentônicos em um riacho de floresta urbana na região do sudeste brasileiro. Os invertebrados foram coletados em um riacho de cabeceira, localizado na Floresta da Tijuca, Rio de Janeiro. Três tipos de microhabitats foram amostrados (folhiço, areia e pedra) usando um amostrador Surber. Os espécimes foram identificados em nível de família e curvas de rarefação foram construídas para a amostragem total e para cada tipo de microhabitat. Índices de estrutura de comunidade (abundância, riqueza taxonômica, diversidade e dominância) foram calculados para cada microhabitat. Diferenças entre os índices foram testados através de uma ANOVA de medidas repetidas, e diferenças entre a composição dos microhabitats através de uma PerMANOVA. Um total de 9,800 espécimes foram registrados em que Chironomidae foi mais abundante. As curvas de rarefação não atingiram a assíntota. Os índices de estrutura de comunidades apresentam diferenças (RM ANOVA; p 0.001), bem como a composição dos microhabitats (PerMANOVA; p 0.001). Abundância e riqueza taxonômica foram maiores em folhiço, diversidade foi maior em folhiço e pedra, e areia teve a maior dominância. Os resultados expostos destacaram que a variedade de microhabitats pode aumentar a diversidade local, e que as diferenças na disponibilidade de recursos de cada tipo de microhabitat determina a distribuição desses invertebrados.

12.
Iheringia. Sér. Zool. ; 111: e2021020, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32635

Resumo

This work aimed to assess the diversity and microhabitat use of benthic invertebrates in an urban forest stream in southeastern Brazilian region. The invertebrates were sampled in a headwater stream, located at the Tijuca Forest, Rio de Janeiro. Three types of microhabitats were sampled (litter, sand and stone) using a Surber sampler. Specimens were identified to the family-level and rarefaction curves were constructed for the total sampling and for each type of microhabitat. Community structure indices (abundance, taxonomic richness, diversity, and dominance) were calculated for each microhabitat. Differences among indices were tested through a repeated measure ANOVA, and differences among microhabitatsʼ composition through a PerMANOVA. A total of 9,800 specimens were registered in which Chironomidae was the most abundant. The rarefaction curves did not reach the asymptote. Community structure indices exhibited differences (RM ANOVA; p < 0.001), as well as microhabitats composition (PerMANOVA; p < 0.001). Abundance and taxonomic richness were the highest in litter, diversity was higher both in litter and stone, and sand had the highest dominance. Results highlighted that the variety of microhabitats may enhance local diversity and that the differences in resources availability of each type of microhabitat determine the distribution of these invertebrates.(AU)


Diversidade e uso de microhabitat de invertebrados bentônicos de um riacho de floresta urbana (Sudeste do Brasil). Este trabalho teve como objetivo avaliar a diversidade e o uso de microhabitat de invertebrados bentônicos em um riacho de floresta urbana na região do sudeste brasileiro. Os invertebrados foram coletados em um riacho de cabeceira, localizado na Floresta da Tijuca, Rio de Janeiro. Três tipos de microhabitats foram amostrados (folhiço, areia e pedra) usando um amostrador Surber. Os espécimes foram identificados em nível de família e curvas de rarefação foram construídas para a amostragem total e para cada tipo de microhabitat. Índices de estrutura de comunidade (abundância, riqueza taxonômica, diversidade e dominância) foram calculados para cada microhabitat. Diferenças entre os índices foram testados através de uma ANOVA de medidas repetidas, e diferenças entre a composição dos microhabitats através de uma PerMANOVA. Um total de 9,800 espécimes foram registrados em que Chironomidae foi mais abundante. As curvas de rarefação não atingiram a assíntota. Os índices de estrutura de comunidades apresentam diferenças (RM ANOVA; p < 0.001), bem como a composição dos microhabitats (PerMANOVA; p < 0.001). Abundância e riqueza taxonômica foram maiores em folhiço, diversidade foi maior em folhiço e pedra, e areia teve a maior dominância. Os resultados expostos destacaram que a variedade de microhabitats pode aumentar a diversidade local, e que as diferenças na disponibilidade de recursos de cada tipo de microhabitat determina a distribuição desses invertebrados.(AU)


Assuntos
Biodiversidade , Flora Bentônica/análise , Rios , Substratos para Tratamento Biológico/análise
13.
Iheringia, Sér. zool ; 111: e2021020, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1483425

Resumo

This work aimed to assess the diversity and microhabitat use of benthic invertebrates in an urban forest stream in southeastern Brazilian region. The invertebrates were sampled in a headwater stream, located at the Tijuca Forest, Rio de Janeiro. Three types of microhabitats were sampled (litter, sand and stone) using a Surber sampler. Specimens were identified to the family-level and rarefaction curves were constructed for the total sampling and for each type of microhabitat. Community structure indices (abundance, taxonomic richness, diversity, and dominance) were calculated for each microhabitat. Differences among indices were tested through a repeated measure ANOVA, and differences among microhabitatsʼ composition through a PerMANOVA. A total of 9,800 specimens were registered in which Chironomidae was the most abundant. The rarefaction curves did not reach the asymptote. Community structure indices exhibited differences (RM ANOVA; p < 0.001), as well as microhabitats’ composition (PerMANOVA; p < 0.001). Abundance and taxonomic richness were the highest in litter, diversity was higher both in litter and stone, and sand had the highest dominance. Results highlighted that the variety of microhabitats may enhance local diversity and that the differences in resources availability of each type of microhabitat determine the distribution of these invertebrates.


Diversidade e uso de microhabitat de invertebrados bentônicos de um riacho de floresta urbana (Sudeste do Brasil). Este trabalho teve como objetivo avaliar a diversidade e o uso de microhabitat de invertebrados bentônicos em um riacho de floresta urbana na região do sudeste brasileiro. Os invertebrados foram coletados em um riacho de cabeceira, localizado na Floresta da Tijuca, Rio de Janeiro. Três tipos de microhabitats foram amostrados (folhiço, areia e pedra) usando um amostrador Surber. Os espécimes foram identificados em nível de família e curvas de rarefação foram construídas para a amostragem total e para cada tipo de microhabitat. Índices de estrutura de comunidade (abundância, riqueza taxonômica, diversidade e dominância) foram calculados para cada microhabitat. Diferenças entre os índices foram testados através de uma ANOVA de medidas repetidas, e diferenças entre a composição dos microhabitats através de uma PerMANOVA. Um total de 9,800 espécimes foram registrados em que Chironomidae foi mais abundante. As curvas de rarefação não atingiram a assíntota. Os índices de estrutura de comunidades apresentam diferenças (RM ANOVA; p < 0.001), bem como a composição dos microhabitats (PerMANOVA; p < 0.001). Abundância e riqueza taxonômica foram maiores em folhiço, diversidade foi maior em folhiço e pedra, e areia teve a maior dominância. Os resultados expostos destacaram que a variedade de microhabitats pode aumentar a diversidade local, e que as diferenças na disponibilidade de recursos de cada tipo de microhabitat determina a distribuição desses invertebrados.


Assuntos
Biodiversidade , Flora Bentônica/análise , Rios , Substratos para Tratamento Biológico/análise
14.
Iheringia. Sér. Zool. ; 111: e2021013, 2021. mapas, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-764763

Resumo

Climatic conditions and microhabitat characteristics, such as the substrate and type of vegetation, influence the choice of male anurans for calling sites that optimize their reproductive success. We evaluated the structure and selection of vocalization microhabitat of 17 individuals of Phyllomedusa distincta Lutz, 1950 and 25 of Boana leptolineata (Braun & Braun, 1977), in a subtropical forest in southern Brazil. We measure the height of the perch, the distance between the perch and the edge of the body of water and the structure of the microhabitat of quadrants used by individuals. The same attributes were measured in the quadrants available (but not used) by the individuals. We classified the microhabitats by visual estimate, assigning percentages of coverage for each quadrant by herbaceous, shrub, tree and wetland vegetation. We observed that both species selected their microhabitat, since the characteristics of the quadrants occupied by the individuals were different from those available. Phyllomedusa distincta was more associated with heterogeneous microhabitats, while B. leptolineata occurred in environments with greater coverage of tree strata. Additionally, we observed that both species used shrubs more frequently as a perch site. The selection of these microhabitat characteristics must be associated with strategies to optimize the use of the reproductive habitat, based on the morphological and behavioral characteristics of the species. Finally, it is possible to infer that the differences observed in the microhabitat structure selected by the species can facilitate the coexistence of both in the context of the heterogeneity of the environment.(AU)


Seleção e uso de sítios de vocalização por Boana leptolineata e Phyllomedusa distincta durante o período reprodutivoAs condições climáticas e as características de micro-habitat, como o substrato e o tipo de vegetação, influenciam a escolha de anuros machos por sítios de vocalização que otimizem seu sucesso reprodutivo. Avaliamos a estrutura e a seleção de micro-habitat de vocalização de 17 indivíduos de Phyllomedusa distincta Lutz, 1950 e 25 de Boana leptolineata (Braun & Braun, 1977), em uma floresta subtropical no sul do Brasil. Medimos a altura do poleiro, a distância do poleiro até a margem do corpo dágua e a estrutura do micro-habitat de quadrantes utilizados pelos indivíduos. Os mesmos atributos foram mensurados nos quadrantes disponíveis (mas não utilizados) pelos indivíduos. Classificamos os micro-habitats por estimativa visual, atribuindo-se porcentagens de cobertura de cada quadrante por vegetação herbácea, arbustiva, arbórea e de área alagada. Observamos que ambas as espécies selecionaram seu micro-habitat, uma vez que as características dos quadrantes ocupados pelos indivíduos foram distintas daquelas disponíveis. Phyllomedusa distincta esteve mais associada a micro-habitats heterogêneos, enquanto B. leptolineata ocorreu em ambientes com maior cobertura de estrato arbóreo. Adicionalmente, observamos que ambas as espécies utilizaram mais frequentemente arbustos como local do poleiro. A seleção destas características de micro-habitat deve estar associada a estratégias para otimização do uso do habitat reprodutivo, baseadas em características morfológicas e comportamentais das espécies. Por fim, é possível inferir que as diferenças observadas na estrutura de micro-habitat selecionadas pelas espécies podem facilitar a coexistência de ambas no contexto da heterogeneidade do ambiente.(AU)


Assuntos
Animais , Anfíbios/embriologia , Comportamento Reprodutivo , Ecossistema
15.
Iheringia, Sér. zool ; 111: e2021013, 2021. map, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1483419

Resumo

Climatic conditions and microhabitat characteristics, such as the substrate and type of vegetation, influence the choice of male anurans for calling sites that optimize their reproductive success. We evaluated the structure and selection of vocalization microhabitat of 17 individuals of Phyllomedusa distincta Lutz, 1950 and 25 of Boana leptolineata (Braun & Braun, 1977), in a subtropical forest in southern Brazil. We measure the height of the perch, the distance between the perch and the edge of the body of water and the structure of the microhabitat of quadrants used by individuals. The same attributes were measured in the quadrants available (but not used) by the individuals. We classified the microhabitats by visual estimate, assigning percentages of coverage for each quadrant by herbaceous, shrub, tree and wetland vegetation. We observed that both species selected their microhabitat, since the characteristics of the quadrants occupied by the individuals were different from those available. Phyllomedusa distincta was more associated with heterogeneous microhabitats, while B. leptolineata occurred in environments with greater coverage of tree strata. Additionally, we observed that both species used shrubs more frequently as a perch site. The selection of these microhabitat characteristics must be associated with strategies to optimize the use of the reproductive habitat, based on the morphological and behavioral characteristics of the species. Finally, it is possible to infer that the differences observed in the microhabitat structure selected by the species can facilitate the coexistence of both in the context of the heterogeneity of the environment.


Seleção e uso de sítios de vocalização por Boana leptolineata e Phyllomedusa distincta durante o período reprodutivoAs condições climáticas e as características de micro-habitat, como o substrato e o tipo de vegetação, influenciam a escolha de anuros machos por sítios de vocalização que otimizem seu sucesso reprodutivo. Avaliamos a estrutura e a seleção de micro-habitat de vocalização de 17 indivíduos de Phyllomedusa distincta Lutz, 1950 e 25 de Boana leptolineata (Braun & Braun, 1977), em uma floresta subtropical no sul do Brasil. Medimos a altura do poleiro, a distância do poleiro até a margem do corpo d’água e a estrutura do micro-habitat de quadrantes utilizados pelos indivíduos. Os mesmos atributos foram mensurados nos quadrantes disponíveis (mas não utilizados) pelos indivíduos. Classificamos os micro-habitats por estimativa visual, atribuindo-se porcentagens de cobertura de cada quadrante por vegetação herbácea, arbustiva, arbórea e de área alagada. Observamos que ambas as espécies selecionaram seu micro-habitat, uma vez que as características dos quadrantes ocupados pelos indivíduos foram distintas daquelas disponíveis. Phyllomedusa distincta esteve mais associada a micro-habitats heterogêneos, enquanto B. leptolineata ocorreu em ambientes com maior cobertura de estrato arbóreo. Adicionalmente, observamos que ambas as espécies utilizaram mais frequentemente arbustos como local do poleiro. A seleção destas características de micro-habitat deve estar associada a estratégias para otimização do uso do habitat reprodutivo, baseadas em características morfológicas e comportamentais das espécies. Por fim, é possível inferir que as diferenças observadas na estrutura de micro-habitat selecionadas pelas espécies podem facilitar a coexistência de ambas no contexto da heterogeneidade do ambiente.


Assuntos
Animais , Anfíbios/embriologia , Comportamento Reprodutivo , Ecossistema
16.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487484

Resumo

Abstract The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.

17.
Pap. avulsos zool ; 61: e20216170, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1340294

Resumo

Abstract The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards' populations.

18.
Pap. avulsos Zool. ; 61: e20216170, 2021. mapas, ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-33279

Resumo

The high mountain environment is a tough habitat that imposes many challenges to reptiles. As temperature decreases with altitude and has a dramatic variation throughout the day in the tropical mountains, ectotherms must cope with these harsh conditions. We studied the use of microhabitat and activity patterns of Stenocercus trachycephalus in the eastern Andes mountain range of Colombia. Three localities were sampled across the wide altitudinal distribution of this lizard species, in a range from 2,670 to 3,950 m a.s.l. The initial hypothesis was that these natural history traits would change with altitude but instead, we found that they remained roughly consistent, showing the great plasticity of this species. The results support that this lizard is a microhabitat-generalist using principally herb across the gradient, rarely shifting to specific plants or microhabitats such as rocks depending on availability. Regarding the activity pattern, this species was active throughout the day from 8:00 to 16:00 with a similar pattern along the gradient. Nevertheless, some differences were detected across localities. The activity pattern shifted from bimodal in the lower locality to unimodal in the higher ones. As expected, a correlation between temperature and activity patterns was found in one of the study sites. However, this was not the case for the lower and mid-elevation localities, where there was no correlation between these variables. The mid-elevation study site was the most interesting locality as the use of microhabitat relied virtually just on the herb stratum and the activity was constrained to the morning hours. These findings may be the result of the synergic effects of other ecological variables (weather variability, human impact, predation, population structure, or reproductive season). Our study gives the basis for a better understanding of how behavior (microhabitat choice and hours of activity) of ectotherms can help to counter thermal constraints in the neotropics when facing an altitudinal gradient. Further studies should focus on the thermal biology of this species, considering the influence of anthropic impact on these lizards populations.(AU)


Assuntos
Animais , Iguanas/anatomia & histologia , Iguanas/classificação , Ecossistema , Ecologia
19.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487433

Resumo

Abstract Ecosystem engineering species create, modify, and/or maintain the characteristics of the environment. The polychaete Phragmatopoma caudata builds large sand reefs in the intertidal region of the Brazilian coast with high structural complexity, favoring the increase of diversity and interactions among the species associated. However, there are no studies concerning the association of polychaetes with crustacean macrofauna in the northeastern Brazil ecoregion, leaving an information gap on baseline biodiversity. Our aim was to analyze the effect of P. caudata colonies (PC) on the local diversity of macrocrustaceans compared to the rocky shore (RS) microhabitat. Monthly collections were carried out in low tide from September 2015 to August 2016 on 10 × 10 m quadrants for fauna and environmental variables (temperature and salinity) samples. In each microhabitat, the capture effort was two hours by two researchers. We collected 3,390 individuals, 60% associated with the colonies of PC and 40% with the RS. The PC obtained higher Shannon diversity, Pielou evenness and species richness coupled with milder water temperature and salinity conditions (minor air exposure during tide), compared to the RS that obtained greater species dominance and more extreme abiotic conditions (major air exposure). The Porcellanidae family stood out because all its species were highly abundant and had high occurrence in the colonies. The tropical Brazil porcelain crab Pachycheles greeleyi was dominant in both microhabitats (major dominance in PC). The structural complexity in the reefs of PC promoted higher availability of niches for the species, as more shelter for the resident species and refugium for temporary species with preference for more complex microhabitats. Conservation managers should prioritize the health of these colonies and subsequent species that constitute important ecosystemic and fishery resources.

20.
Pap. avulsos zool ; 61: e20216119, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1287458

Resumo

Abstract Ecosystem engineering species create, modify, and/or maintain the characteristics of the environment. The polychaete Phragmatopoma caudata builds large sand reefs in the intertidal region of the Brazilian coast with high structural complexity, favoring the increase of diversity and interactions among the species associated. However, there are no studies concerning the association of polychaetes with crustacean macrofauna in the northeastern Brazil ecoregion, leaving an information gap on baseline biodiversity. Our aim was to analyze the effect of P. caudata colonies (PC) on the local diversity of macrocrustaceans compared to the rocky shore (RS) microhabitat. Monthly collections were carried out in low tide from September 2015 to August 2016 on 10 × 10 m quadrants for fauna and environmental variables (temperature and salinity) samples. In each microhabitat, the capture effort was two hours by two researchers. We collected 3,390 individuals, 60% associated with the colonies of PC and 40% with the RS. The PC obtained higher Shannon diversity, Pielou evenness and species richness coupled with milder water temperature and salinity conditions (minor air exposure during tide), compared to the RS that obtained greater species dominance and more extreme abiotic conditions (major air exposure). The Porcellanidae family stood out because all its species were highly abundant and had high occurrence in the colonies. The tropical Brazil porcelain crab Pachycheles greeleyi was dominant in both microhabitats (major dominance in PC). The structural complexity in the reefs of PC promoted higher availability of niches for the species, as more shelter for the resident species and refugium for temporary species with preference for more complex microhabitats. Conservation managers should prioritize the health of these colonies and subsequent species that constitute important ecosystemic and fishery resources.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA