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1.
Pap. avulsos zool ; 63: e202363007, 2023. ilus, tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1419205

Resumo

The Maguari Stork (Ciconia maguari) is one of the three species of the family Ciconiidae that occur in South America. Despite abundant in landscapes dominated by wetlands and grasslands, detailed studies on its biology are scarce. This study is aimed at investigating aspects of the breeding of Maguari Storks in Brazil. Photographic records were searched in the WikiAves database. A total of 65 records, obtained by citizens along 13 years in 32 municipalities, showed evidences of breeding activities in Brazil. Most (86%) of these records were gathered in the Pampa biome, in southern Brazil. Nests were large platforms and contained 1-3 young. Nests built on the ground were in grasslands or reed patches. Those built on shrubs were at boundaries between lakes and grasslands, and were often in colonial nesting sites with egrets and herons. Incubation occurred between July and November, and nestlings were found between August and December. Juveniles able to fly were recorded between late October and February. Most records of breeding activities were obtained at sites located < 300 m above sea level. As the Maguari Stork is a conspicuous and charismatic species, its conservation could substantially benefit from the awareness of landowners to promote eco-tourism in their properties, attracting birdwatchers. For this, it should be ensured the integrity of grasslands, marshes, and lakes with microhabitats often used for nesting (woody plants and reed patches).(AU)


Assuntos
Aves/fisiologia , Fenômenos Reprodutivos Fisiológicos , Brasil , Ecossistema
2.
Acta amaz ; 52(3): 236-240, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1392848

Resumo

The relationship between Odonata and vegetation in Amazonia has been studied primarily in streams. In this study, I examined the abundance of adult Odonata in two vegetation types (shrubs and herbs) surrounding an oxbow lake in the Peruvian Amazon. Daytime visual samplings of Odonata were carried out in time blocks along transects in each habitat. Thirteen taxa were identified. Five species were similarly abundant in both habitats, three used mainly herbs, and one mainly shrubs, with no variation among time blocks. The results suggest that most Anisoptera and Zygoptera are adapted to unshaded areas of the lake. Some Odonata also were observed during sunless days with light rainfall, suggesting they are adapted to rainy conditions in tropical climate.(AU)


La relación entre Odonata y vegetación en la Amazonía ha sido estudiada principalmente en arroyos. En este estudio, se examinó la abundancia de adultos de Odonata en dos tipos de vegetación (arbustos y hierbas) alrededor de un lago de herradura en la Amazonía peruana. Muestreos visuales diurnos fueron realizados en bloques temporales a lo largo de cada hábitat. Trece taxones fueron identificados. Cinco especies fueron similarmente abundantes en los dos tipos de hábitat, tres usaron principalmente hierbas y una principalmente arbustos, esto no varió entre los bloques temporales. Los resultados sugieren que la mayoría de Anisoptera y Zygoptera están adaptados a áreas sin sombra del lago. Algunas libélulas fueron observadas durante días sin sol y con llovizna, sugiriendo que se encuentran adaptadas a condiciones de lluvia en climas tropicales.(AU)


Assuntos
Animais , Especificidade da Espécie , Odonatos/classificação , Distribuição Animal/fisiologia , Peru , Ecossistema Amazônico
3.
Iheringia, Sér. zool ; 112: e2022025, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1421636

Resumo

Cattle in wetlands impact water quality through waste excretion, which deposits excess nutrients, as well as decreasing the biomass and height of vegetation through trampling and herbivory. Amphibians are sensitive to these changes due to their porous skin and reliance on vegetated microhabitats. Previous studies examining the effect of cattle on amphibians in wetlands report conflicting results, exemplifying the need to avoid overgeneralizations and instead examine specific environments. In the Ñeembucú Wetland Complex in Paraguay, low-intensity cattle ranching is a common practice. This study seeks to understand how the presence of cattle in these operations impacts water chemistry and amphibian species richness, as well as determining which cattle effects (eutrophication, nutrient loading, and decreased vegetation height diversity) have the greatest impact on amphibian communities. We anticipated that increased cattle presence would negatively impact wetland condition, and consequentially lower amphibian species richness. Data was collected over seven weeks at Estancia Santa Ana, a low-intensity cattle ranch in Pilar, Paraguay. Cattle presence was measured through cow footprints and feces densities, while a vegetation survey and water quality testing (nitrate, phosphate, and dissolved oxygen) served as environmental metrics. Pitfall trapping was used to gather information on amphibian species richness and community composition. A Pearson parametric correlation test and Factor Analysis of Mixed Data in R were then used to understand the relationship between variables. Very few statistically relationships were found between variables, and those that existed showed a very weak correlation. This suggests that cow presence does not have as strong of an impact on water quality or amphibian species richness as expected. Terrestrial and aquatic vegetation were found to explain much of the variation among the data, which verifies the importance of amphibians' microhabitats. While future research comparing generalist and specialist species in the area is necessary, these initial results suggest a hopeful future for collaboration on environmental efforts with low-intensity cattle ranchers.(AU)


Efectos de la ganadería de baja intensidad sobre los anfibios en el Complejo de Humedales Ñeembucú, Paraguay. La ganadería en los humedales afecta a la calidad del agua por excreción que añade nutrientes excesivos, además de reducir la altura y biomasa de vegetación a causa de pisar y comerla. Los anfibios son sensibles a estos cambios a causa de su piel porosa y su dependencia de la vegetación como hábitat. Estudios anteriores que investigaban los efectos del ganado en anfibios descubrieron resultados en conflicto, y así es importante evitar generalizar sobre todas las especies y ambientes. En los humedales de Ñeembucú en Paraguay, los ranchos con una densidad baja de vaca y un cambio mínimo al ambiente son muy comunes. Esta investigación trata de entender como la presencia del ganado en los ranchos afecta la calidad del agua y la riqueza de especies de anfibios, además de cuales factores (eutrofización, nutrientes excesivos o menos diversidad de vegetación) tienen el impacto más grande en los anfibios. Esperábamos que una presencia más alta de ganado causaría daño a la calidad del agua, y por eso, habría menos especies de anfibios presentes. Los datos se recogieron por siete semanas en Estancia Santa Ana, una estancia cerca a Pilar, Paraguay. La presencia de la ganadería se midió por la densidad de heces y huellas, y el medioambiente se analizó por un estudio de la vegetación y pruebas del agua (nitrato, fosfato y oxígeno). Se usan trampas pozos para capturar las ranas y coleccionar información sobre la riqueza de especies y la composición de la comunidad. Se usa la prueba de correlación paramétrica de Pearson y un Factor Analysis of Mixed Data en R para entender las relaciones entre las variables. Pocas relaciones de significado estadístico existen, y las que existen muestran una correlación muy débil. Eso sugiere que la ganadería no tenga un impacto muy grande en la calidad del agua o la riqueza de las especies como esperábamos. Vegetación terrestre y acuática explica la mayoría de la variación en los datos, y eso confirma la importancia de los hábitats de los anfibios. Los resultados sugieren un futuro optimista en cuanto a la colaboración entre los esfuerzos de conservación y los rancheros.(AU)


Assuntos
Animais , Poluição Química da Água , Anfíbios , Criação de Animais Domésticos , Paraguai , Eutrofização
4.
Bol. Inst. Pesca (Impr.) ; 48: e651, 2022. mapas, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1400918

Resumo

The presence or absence of a fish species may be associated with the physical and chemical characteristics of the water, in addition to the state of preservation of the riparian zone. This study examined whether the taxonomic fish composition in an urban river varies along three riparian zone preservation conditions: preserved, intermediate preservation and degraded. Six urban stretches of the Sorocaba/São Paulo River were selected for this study, with monthly sampling being carried out from June 2019 to February 2020. The samplings were carried out with the aid of a sieve, dip net, and trawl. Regarding the types of margins and environmental variables, the Principal Component Analysis explained 97.49% of the data variation, axis 1, which explained 91.85% of the total variation, was formed by the variables conductivity and total dissolved solids. Axis 2, which explained 5.64% of the variation, was formed by Sun Rays% and Siltation%, being inversely proportional to Riparian Forest%. For the ichthyofauna, the samples consisted in 50,983 fish distributed in 5 orders, 8 families, and 12 species. Cyprinodontiformes had the highest abundance, with 96.96% of the total number of individuals, followed by Siluriformes (2.39%), and the sum of the other orders did not reach 1% of the total collected. According to each type of margin, it was possible to register 11,592 individuals for the Margin A ­ preserved, with S=8 species, being 2 exclusive (Corydoras flaveolus and Hoplosternum littorale) and 3 exotic (Coptodon rendalli, Pterygoplichthys ambrosettii, and Poecilia reticulata), the latter was dominant in all types of margins. For Margin B ­ intermediate preservation, 19,645 individuals were sampled, with S=5 species, no exclusive species, only exotic and more tolerant native species such as Hoplias malabaricus and Hypostomus ancistroides. For Margin C ­ degraded, 19,746 individuals were recorded, the largest number of species (S=10), 3 were exclusive to this type of mar-gin (Psalidodon fasciatus, Rhamdia Quelen, and Geophagus brasiliensis). The pairwise comparison (similarity percentage) showed that the assemblage structure was different for the types of margins. The Canonical Cor-respondence Analysis explained 92.46% of the total data variation, showing the relationship of species to envi-ronmental data. It is evident the importance of preservation of micro-habitats still present in the locals sampled, since different anthropic pressures cause great loss of diversity, especially for native and more sensitive species.


A presença ou ausência de uma espécie de peixe que vive em rios urbanos pode estar associada às características físicas e químicas da água, além do estado de preservação da zona ripária. O presente estudo verificou se a composição taxonômica de peixes de um rio urbano varia em três condições de preservação da zona ripária: preservada, preservação intermediária e degradada. Seis trechos urbanos do rio Sorocaba, localizado no estado de São Paulo, foram selecionados para este estudo, com coletas mensais de junho de 2019 a fevereiro de 2020 com auxílio de peneira, puçá e rede de arrasto. Com relação aos tipos de margens e às variáveis ambientais, a análise de componentes principais explicou 97,49% da variação dos dados. O eixo 1, que explicou 91,85% da variação total, foi formado pelas variáveis condutividade e total de sólidos dissolvidos. O eixo 2, que explicou 5,64% da variação, foi formado pelo percentual das variáveis raios solares e assoreamento, revelando-se inversamente proporcional ao de mata ripária. Para a ictiofauna, foram amostrados 50.983 indivíduos compreendidos em cinco ordens, oito famílias e 12 espécies. Cyprinodontiformes apresentou maior abundância, com 96,96% do total de indivíduos, seguida de siluriformes (2,39%); a soma das demais ordens não atingiu 1% do total coletado. De acordo com cada tipo de margem, foi possível registrar 11.592 indivíduos para a margem A preservada, com a s=8 espécies, das quais duas foram exclusivas (C. flaveolus e H. littorale) e três exóticas (C. rendalli, P. ambrosettii e P. reticulata), sendo esta última dominante em todos os tipos de margens. Para a margem B intermediária, foram amostrados 19.645 indivíduos, com S=5 espécies, dos quais nenhum representante de espécie exclusiva, apenas espécies exóticas e nativas mais tolerantes, como H. malabaricus e H. ancistroides. Já para margem C degradada, foram registrados 19.746 exemplares, maior número de espécies (s=10), três delas exclusivas desse tipo de margem (P. fasciatus, R. quelen e G. brasiliensis). A comparação par a par (porcentagem similar) mostrou que a estrutura da assembleia se apresentou distinta para os tipos de margens. A análise de correspondência canônica explicou 92,46% da variação total dos dados, evidenciando a relação das espécies com os dados ambientais. Torna-se evidente a importância da preservação dos micro-habitatsainda presentes nas margens amostradas, visto que diferentes pressões antrópicas causam grande perda de diversidade, sobretudo para espécies nativas e espécies mais sensíveis a essas alterações.


Assuntos
Animais , Ecossistema , Peixes/classificação , Brasil , Biodiversidade , Rios
5.
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.

6.
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
7.
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
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-1487462

Resumo

Abstract A literature survey for the external morphology of tadpoles for species in the genus CycloramphusTschudi, 1838, which is mainly represented by larval descriptions, resulted in finding some inconsistent character descriptions. In a few cases, some of the information is either not presented or mistakenly reported; in some cases, the illustrations provided the information not present in the descriptions. Here in we use a sample of tadpoles of an insular population identified as Cycloramphus boraceiensis, present a description for it, compare it to the original larval description for this species, and using it as a model, present a comparative review of the other larval descriptions for Cycloramphus tadpoles. We evaluate that most of the mistakes we found in the literature are associated to the unique morphology of these semiterrestrial larvae and some of their seemingly adaptation to their microhabitats, which for the majority of the known species is a film of water running associated to or near streams.

10.
Pap. avulsos zool ; 61: e20216148, 2021. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1287453

Resumo

Abstract A literature survey for the external morphology of tadpoles for species in the genus CycloramphusTschudi, 1838, which is mainly represented by larval descriptions, resulted in finding some inconsistent character descriptions. In a few cases, some of the information is either not presented or mistakenly reported; in some cases, the illustrations provided the information not present in the descriptions. Here in we use a sample of tadpoles of an insular population identified as Cycloramphus boraceiensis, present a description for it, compare it to the original larval description for this species, and using it as a model, present a comparative review of the other larval descriptions for Cycloramphus tadpoles. We evaluate that most of the mistakes we found in the literature are associated to the unique morphology of these semiterrestrial larvae and some of their seemingly adaptation to their microhabitats, which for the majority of the known species is a film of water running associated to or near streams.

11.
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.

12.
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.

13.
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
14.
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
15.
Bol. Inst. Pesca (Impr.) ; 47: e634, 2021. map, graf
Artigo em Inglês | VETINDEX | ID: biblio-1465511

Resumo

Several tropical freshwater fish species are generally generalistic feeders, sometimes followed by a diet reduction during the period of decreased resource availability. This study aimed to analyze the dietary overlap between nektonic and benthic fish species. The stomachs of 82 obligatory nektonics and 52 benthic were removed. The diet composition for each individual was determined based on the analysis of the stomach content, and the contents were grouped into 11 categories. For the analysis of food items, the method of degree of food preference was used. To verify the niche overlap between benthic and nectonic, the Pianka index was applied. Benthic species consumed items across all 11 food categories and nektonic species consumed nine. The diet composition of species with nektonic and benthic habits showed a significant difference. Dietary overlapping suggests a supply of the same resources, as they are shared by both groups. The high concentration of water insect larvae in the food content of all sampled fish species, regardless of the position in the water column, shows the importance of insects in the water ecosystems. The composition of ecosystem diets is helpful towards understanding the community structure and can explain the coexistence between different fish’s groups where live in different micro-habitats and how tactics used to capture food which may minimize the effects of overlapping and competitive exclusion.


Várias espécies de peixes de água doce são generalistas, podendo seguir uma redução da dieta durante a diminuição da disponibilidade de recursos. Este estudo analisou a sobreposição alimentar entre peixes nectônicos e bentônicos. Foram retirados os estômagos de 82 indivíduos nectônicos e 52 bentônicos. A composição da dieta para cada indivíduo foi determinada com base na análise do conteúdo estomacal e os itens da dieta foram agrupados em 11 categorias. Para a análise dos itens alimentares foi utilizado o método do grau de preferência alimentar. Para verificar a sobreposição de nicho entre bentônicos e nectônicos aplicou-se o índice de Pianka. Os bentônicos consumiram 11 itens alimentares e os nectônicos, nove. A composição da dieta das espécies com hábitos nectônicos e bentônicos apresentaram diferença significativa. A sobreposição alimentar sugere a oferta dos mesmos recursos pois são compartilhados por ambos os grupos. A elevada participação de larvas de insetos aquáticos no conteúdo alimentar dos peixes, independentemente da posição na coluna d’água, evidencia a importância dos insetos para os ecossistemas aquáticos. A composição do conteúdo alimentar é importante para compreensão da estrutura das comunidades e pode explicar a coexistência entre diferentes grupos de peixes que vivem em diferentes microhabitats e como as táticas usadas para capturar alimentos podem minimizar os efeitos da sobreposição e exclusão competitiva.


Assuntos
Animais , Fauna Bentônica/análise , Peixes/metabolismo , Recursos Alimentares
16.
B. Inst. Pesca ; 47: e634, 2021. mapas, graf
Artigo em Inglês | VETINDEX | ID: vti-765375

Resumo

Several tropical freshwater fish species are generally generalistic feeders, sometimes followed by a diet reduction during the period of decreased resource availability. This study aimed to analyze the dietary overlap between nektonic and benthic fish species. The stomachs of 82 obligatory nektonics and 52 benthic were removed. The diet composition for each individual was determined based on the analysis of the stomach content, and the contents were grouped into 11 categories. For the analysis of food items, the method of degree of food preference was used. To verify the niche overlap between benthic and nectonic, the Pianka index was applied. Benthic species consumed items across all 11 food categories and nektonic species consumed nine. The diet composition of species with nektonic and benthic habits showed a significant difference. Dietary overlapping suggests a supply of the same resources, as they are shared by both groups. The high concentration of water insect larvae in the food content of all sampled fish species, regardless of the position in the water column, shows the importance of insects in the water ecosystems. The composition of ecosystem diets is helpful towards understanding the community structure and can explain the coexistence between different fishs groups where live in different micro-habitats and how tactics used to capture food which may minimize the effects of overlapping and competitive exclusion.(AU)


Várias espécies de peixes de água doce são generalistas, podendo seguir uma redução da dieta durante a diminuição da disponibilidade de recursos. Este estudo analisou a sobreposição alimentar entre peixes nectônicos e bentônicos. Foram retirados os estômagos de 82 indivíduos nectônicos e 52 bentônicos. A composição da dieta para cada indivíduo foi determinada com base na análise do conteúdo estomacal e os itens da dieta foram agrupados em 11 categorias. Para a análise dos itens alimentares foi utilizado o método do grau de preferência alimentar. Para verificar a sobreposição de nicho entre bentônicos e nectônicos aplicou-se o índice de Pianka. Os bentônicos consumiram 11 itens alimentares e os nectônicos, nove. A composição da dieta das espécies com hábitos nectônicos e bentônicos apresentaram diferença significativa. A sobreposição alimentar sugere a oferta dos mesmos recursos pois são compartilhados por ambos os grupos. A elevada participação de larvas de insetos aquáticos no conteúdo alimentar dos peixes, independentemente da posição na coluna dágua, evidencia a importância dos insetos para os ecossistemas aquáticos. A composição do conteúdo alimentar é importante para compreensão da estrutura das comunidades e pode explicar a coexistência entre diferentes grupos de peixes que vivem em diferentes microhabitats e como as táticas usadas para capturar alimentos podem minimizar os efeitos da sobreposição e exclusão competitiva.(AU)


Assuntos
Animais , Fauna Bentônica/análise , Peixes/metabolismo , Recursos Alimentares
17.
Braz. J. Biol. ; 81(1): 164-177, Jan.-Feb. 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-30136

Resumo

Estuaries are used by waterbirds as foraging, resting and nesting sites, serving also as shelter for migratory birds. The dynamics of this avifauna in an aquatic environment may be associated with the differences of time of day, tide height, temperature, wind speed and use of the site by different species. This study had the objective of evaluating behavioral aspects of aquatic birds, relating the influence of environmental variables with their activities. Bird counts were performed at the mouth of two important rivers of the state of Santa Catarina, Brazil, during two-hour intervals throughout the day in monthly samplings between June (2015) and May (2016). A total of 44 species were recorded, ten of which were migratory. The most recorded behaviors were foraging and resting. The Kruskal-Wallis analysis indicated no significant difference in behavior between the sampling intervals. The Bray-Curtis similarity test resulted in three groups: 1) - species that foraged most of the time; 2) - species that rested most of the time; and 3) - same time in both activities. The Indicator Species Analysis showed that 17 species were associated with only one microhabitat and 15 species with more than one. The Canonical Correlation Analysis indicated that only tide height, temperature and rainfall variables were correlated with the behaviors performed and only the resting activity was positively correlated with all variables. This may be associated with thermoregulation and the ability of some species to stay in midlitoral at high tide. The results demonstrate that different waterbird species used the studied areas in different ways. Thus, the heterogeneity of microhabitats in an aquatic environment of extreme importance for the coexistence and maintenance of the diversity of waterbirds.(AU)


Estuários são utilizados por aves aquáticas como locais de forrageio, descanso e nidificação, servindo, também, como pontos de parada para aves migratórias. A dinâmica dessa avifauna em um ambiente pode estar associada a diferenças entre horários do dia, altura da maré, temperatura, velocidade do vento e uso do local. Esse trabalho teve o objetivo de avaliar aspectos comportamentais de aves aquáticas, relacionando a influência de variáveis ambientais com suas atividades. Amostragens mensais foram realizadas na foz de dois importantes rios do Estado de Santa Catarina, Brasil, entre junho de 2015 e maio de 2016, em intervalos de duas horas no decorrer do dia. Um total de 44 espécies foram registradas, dez das quais foram migratórias. Os comportamentos mais observados foram forrageio e descanso. A análise de Kruskall-Wallis não indicou diferenças significativas no comportamento entre os horários de amostragem. O teste de similaridade Bray-Curtis resultou em três agrupamentos: 1) - espécies que forragearam na maior parte do tempo; 2) - espécies que descansaram na maior parte do tempo; e 3) - mesma quantidade de tempo em ambas atividades. A Análise de Espécies Indicadoras mostrou que 17 espécies estiveram associadas com apenas um microhabitat e 15 espécies com mais de um. A Análise de Correlação Canônica indicou que apenas as variáveis maré, temperatura e precipitação foram significativamente correlacionadas com os comportamentos demonstrados e apenas a atividade de descanso foi positivamente correlacionada com as todas as variáveis. Isso pode estar associado com a termorregulação e com a habilidade de algumas espécies de permanecer no mediolitoral durante a maré cheia. Os resultados demonstram que diferentes espécies de aves aquáticas utilizaram as áreas estudadas de diferentes maneiras. Assim, a heterogeneidade de microhabitats em um ambiente aquático é de extrema importância para a coexistência e a manutenção da diversidade de aves.(AU)


Assuntos
Animais , Aves , Fauna Aquática , Comportamento Animal , Estuários
18.
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.

19.
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.

20.
Pap. avulsos Zool. ; 61: e20216119, 2021. mapas, ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765684

Resumo

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.(AU)


Assuntos
Animais , Poliquetos/classificação , Poliquetos/crescimento & desenvolvimento , Ecossistema , Pesqueiros
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