5 resultados para Conopophagidae
Resumo:
Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.
Resumo:
Brazil has the third richest bird diversity of the world; however, there are few data concerning ticks (Acari: Ixodidae) parazitizing birds. The aim of the study was to report tick infestations on wild birds from an Atlantic rain forest region of Brazil. During 2 yr, ticks were collected from birds and from the environment in 12 forest sites. A total of 1,725 birds were captured representing 80 species from 24 families. In total, 223 (13%) birds were found infested by immature stages of Amblyomma ticks: 1,800 larvae and 539 nymphs. The prevalence of ticks was higher among-birds from the families Thamnophilidae, Conopophagidae, and Momotidae. The most common tick parasitizing birds was Amblyomma nodosum Koch. Other tick species, Amblyomma coelebs Neumann, Amblyomma cajennense (F.), Amblyomma ovale Koch, Amblyomma longirostre (Koch), Amblyomma calcaratum Neumann, and Amblyomma naponense (Packard), were found sporadically. Among free-living ticks collected in the environment, A. cajennense was the most common, followed by A. coelebs, A. naponense, Amblyomma brasilense Aragao, and Hemaphysalis juxtakochi Cooley.
Resumo:
Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.
Resumo:
Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)