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1.
Acta amaz ; 53(3): 239-242, July-Sept. 2023. graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1513520

RESUMO

ABSTRACT Facultative kleptoparasites face the risk of trying to steal food resources from competitors. This type of interaction is little known, but anecdotal observations indicate that birds of prey may take advantage of their accurate sight to detect the best opportunities for kleptoparasitism. We recorded a camera trap video of an attempt of kleptoparasitism by the white hawk, Pseudastur albicollis, that tried to steal food from a greater grison, Galictis vittata, in a recently selectively-logged forest site in central Brazilian Amazonia. The attempt was unsuccessful as the greater grison responded aggressively to the attack. The event occurred in a linear clearing, which may have increased the bird's ability to detect its potential host. Kleptoparasitic interactions are difficult to detect in forest environments. Recording opportunistic kleptoparasitic interactions in tropical forests may not only depend on the increasing use of camera traps, but also on habitat conditions that facilitate the detection of potential hosts.


RESUMO Cleptoparasitas facultativos enfrentam os custos envolvidos no roubo do alimento em troca da compensação pelo valor nutricional do item roubado. Essa interação é pouco conhecida, mas observações anedóticas indicam que aves de rapina podem se beneficiar de sua visão acurada para cleptoparasitar. Reportamos uma tentativa de cleptoparasitismo de um furão-grande, Galictis vittata, por um gavião-branco, Pseudastur albicollis, em uma floresta na Amazônia central brasileira recentemente manejada para corte seletivo de impacto reduzido. Como o furão-grande respondeu agressivamente ao ataque, a tentativa de roubo falhou. O evento foi registrado por uma armadilha fotográfica em uma clareira linear. O ambiente mais aberto pode ter aumentado a habilidade do gavião-branco em encontrar o seu hospedeiro. Eventos de cleptoparasitismo são dificilmente registrados em ambientes florestais. Registros de cleptoparasitismo em florestas tropicais podem não depender apenas do uso intensivo de armadilhas fotográficas, mas também de condições ambientais favoráveis à detecção de possíveis hospedeiros pelo cleptoparasita.

2.
An Acad Bras Cienc ; 94(3): e20201654, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857933

RESUMO

Selective logging is one of the main human activities that are drastically modifying tropical forests around the world. Reduced-impact logging emerged as a rational model of timber harvesting that reduces the impacts on the ecosystems and contributes to the conservation of natural resources. Nevertheless, this type of activity may still alter the forest structure, nutrient cycling, soil drainage, and other important ecosystem processes. Here, we aimed at testing the effects of selective logging on litter deposition in central Brazilian Amazonia. We estimated litter production during one dry and one rainy season in 11 sites logged between 2003 and 2017 and one unlogged site. Mean litter deposition was greater during the dry season. Although litter deposition rates varied between a few study sites, this variation was independent of the time after logging. The results suggest that the low logging intensity in the study site (16.8 m³/ha) had no intense impacts on litter deposition. Reduced-impact logging may be an alternative for the use of forest resources in Amazonian forests without compromising nutrient cycles.


Assuntos
Ecossistema , Agricultura Florestal , Brasil , Conservação dos Recursos Naturais/métodos , Florestas , Atividades Humanas , Humanos , Árvores
3.
An Acad Bras Cienc ; 94(1): e20191227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544864

RESUMO

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


Assuntos
Amazona , Animais , Brasil , Conservação dos Recursos Naturais , Ecossistema , Florestas , Solo
4.
PLoS One ; 12(12): e0188819, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29228053

RESUMO

Data generated by citizen science is particularly valuable in ecological research. If used discerningly with data from traditional scientific references, citizen science can directly contribute to biogeography knowledge and conservation policies by increasing the number of species records in large geographic areas. Considering the current level of knowledge on south Brazilian avifauna, the large volume of data produced by uncoordinated citizen science effort (CS), and the growing need for information on changes in abundance and species composition, we have compiled an updated, general list of bird species occurrence within the state of Paraná. We have listed extinct, invasive and recently-colonizing species as well as indicator species of the state's vegetation types. We further assess the degree of knowledge of different regions within the state based on data from traditional scientific references, and the effect of including CS data in the same analysis. We have compiled data on 766 bird species, based on 70,346 individual records from traditional scientific references, and 79,468 from CS. Extinct and invasive species were identified by comparing their occurrence and abundance over a series of three time periods. Indicator species analysis pointed to the existence of three areas with bird communities typically found within the state: the Semideciduous Tropical Forest, the Tropical Rainforest and the junction of Grassland and Araucaria Moist Forest. We used rarefaction to measure sampling sufficiency, and found that rarefaction curves reached stabilization for all vegetation types except in Savanna. We observed differences in the level of knowledge of bird biodiversity among the microregions of the state, but including CS data, these differences were mitigated. The same effect was observed in other exploratory analyzes conducted here, emphasizing the fundamental importance of including CS data in macroecological studies. Production of easily accessible data and its unrestricted availability makes CS a very important tool, especially in highly diverse regions as the Neotropics, as it can offer a more accurate picture of bird composition in comparison to the exclusive use of traditional scientific references.


Assuntos
Biodiversidade , Aves , Participação da Comunidade , Conservação dos Recursos Naturais , Plantas , Animais , Brasil
5.
Iheringia. Sér. Zool. ; 103(1): 37-41, mar. 2013. graf, mapas, tab, ilus
Artigo em Português | VETINDEX | ID: vti-30851

RESUMO

The Brown-backed Parrotlet [Touit melanonotus (Wied, 1820)] is a rare forest species restricted to the Brazilian Atlantic Forest, and is included in the endangered category for species threatened of extinction. As there is a lack of knowledge about the species natural history and occurrence, new observations can provide helpful information for parrotlet conservation. Here we reevaluate the first record for the species and present new records for the state of Paraná (southern Brazil). The vocalizations previously attributed to T. melanonotus, and which were used to infer its occurrence in the state, were examined by spectrogram analysis. These were actually found to be vocalizations of the Red-capped Parrot [Pionopsita pileata (Scopoli, 1769)], representing a case of misidentification. Even so, the Brown-backed Parrotlet occurs with some regularity in the state of Paraná, as shown by 12 records spread through seven localities spanning the entire Paraná coast. The Brown-backed Parrotlet was recorded mostly in lowland areas, and as these forest types suffer intense pressures, conservation efforts aiming the species preservation should focus in the maintenance of these habitats.(AU)


O apuim-de-costas-pretas [Touit melanonotus (Wied, 1820)] é uma espécie florestal endêmica da Mata Atlântica Brasileira e de relevante interesse conservacionista. Trata-se de uma ave com poucas informações disponíveis acerca de sua história natural e distribuição geográfica e novas observações são importantes fontes de informação para auxiliar na conservação da espécie. Aqui reavaliamos o primeiro registro da espécie e apresentamos novas observações no estado do Paraná, sul do Brasil. As vocalizações atribuídas a T. melanonotus e que consubstanciaram sua ocorrência no estado foram examinadas com auxílio de espectrogramas e identificadas como vozes de Pionopsitta pileata (Scopoli, 1769). Não obstante, T. melanonotus ocorre com certa regularidade no Paraná, como indicado por novos registros da espécie em sete localidades distribuídas por todo o litoral do estado. Esta ave foi registrada principalmente em florestas de terras baixas e, uma vez que esta fisionomia sofre intensas pressões antrópicas, sugerimos que esforços de conservação da espécie devem priorizar a preservação desses hábitats.(AU)


Assuntos
Animais , Papagaios/crescimento & desenvolvimento , Ecossistema , Doenças Endêmicas
6.
Iheringia, Sér. zool ; 103(1): 37-41, mar. 2013. graf, map, tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1482734

RESUMO

The Brown-backed Parrotlet [Touit melanonotus (Wied, 1820)] is a rare forest species restricted to the Brazilian Atlantic Forest, and is included in the endangered category for species threatened of extinction. As there is a lack of knowledge about the species’ natural history and occurrence, new observations can provide helpful information for parrotlet conservation. Here we reevaluate the first record for the species and present new records for the state of Paraná (southern Brazil). The vocalizations previously attributed to T. melanonotus, and which were used to infer its occurrence in the state, were examined by spectrogram analysis. These were actually found to be vocalizations of the Red-capped Parrot [Pionopsita pileata (Scopoli, 1769)], representing a case of misidentification. Even so, the Brown-backed Parrotlet occurs with some regularity in the state of Paraná, as shown by 12 records spread through seven localities spanning the entire Paraná coast. The Brown-backed Parrotlet was recorded mostly in lowland areas, and as these forest types suffer intense pressures, conservation efforts aiming the species preservation should focus in the maintenance of these habitats.


O apuim-de-costas-pretas [Touit melanonotus (Wied, 1820)] é uma espécie florestal endêmica da Mata Atlântica Brasileira e de relevante interesse conservacionista. Trata-se de uma ave com poucas informações disponíveis acerca de sua história natural e distribuição geográfica e novas observações são importantes fontes de informação para auxiliar na conservação da espécie. Aqui reavaliamos o primeiro registro da espécie e apresentamos novas observações no estado do Paraná, sul do Brasil. As vocalizações atribuídas a T. melanonotus e que consubstanciaram sua ocorrência no estado foram examinadas com auxílio de espectrogramas e identificadas como vozes de Pionopsitta pileata (Scopoli, 1769). Não obstante, T. melanonotus ocorre com certa regularidade no Paraná, como indicado por novos registros da espécie em sete localidades distribuídas por todo o litoral do estado. Esta ave foi registrada principalmente em florestas de terras baixas e, uma vez que esta fisionomia sofre intensas pressões antrópicas, sugerimos que esforços de conservação da espécie devem priorizar a preservação desses hábitats.


Assuntos
Animais , Ecossistema , Papagaios/crescimento & desenvolvimento , Doenças Endêmicas
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