Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
R Soc Open Sci ; 10(11): 231443, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38026037

RESUMO

The primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or ASR towards males. The Harpy Eagle is the world's largest eagle exhibiting RSD. This species is found in the Neotropical region and is currently threatened with extinction. We used molecular markers to determine the sex of 309 Harpy Eagles spanning different life stages-eaglets, subadults and adults-from 1904 to 2021 within the Amazon Rainforest and Atlantic Forest. Sex ratios for all life stages revealed a female-biased deviation across all periods and regions. Our results suggest that the population bias towards females is an evolutionary ecological pattern of this species, and SSR and ASR likely emerged from the PSR. This natural bias towards females may be compensated by an earlier sexual maturation age of males, implying a longer reproductive lifespan and a higher proportion of sexually active males. A better understanding of the Harpy Eagle's life history can contribute to understanding sex-role evolution and enable more appropriate conservation strategies for the species.

2.
An Acad Bras Cienc ; 95(3): e20230051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878914

RESUMO

Long-term-ecological-research (LTER) faces many challenges, including the difficulty of obtaining long-term funding, changes in research questions and sampling designs, keeping researchers collecting standardized data for many years, impediments to interactions with local people, and the difficulty of integrating the needs of local decision makers with "big science". These issues result in a lack of universally accepted guidelines as to how research should be done and integrated among LTER sites. Here we discuss how the RAPELD (standardized field infrastructure system), can help deal with these issues as a complementary technique in LTER studies, allowing comparisons across landscapes and ecosystems and reducing sampling costs. RAPELD uses local surveys to understand broad spatial and temporal patterns while enhancing decision-making and training of researchers, local indigenous groups and traditional communities. Sampling of ecological data can be carried out by different researchers through standardized protocols, resulting in spatial data that can be used to answer temporal questions, and allow new questions to be investigated. Results can also be integrated into existing biodiversity networks. Integrated systems are the most efficient way to save resources, maximize results, and accumulate information that can be used in the face of the unknown unknowns upon which our future depends.


Assuntos
Biodiversidade , Ecossistema , Humanos , Estudos Longitudinais
3.
Sci Rep ; 13(1): 18308, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880262

RESUMO

The Harpy Eagle (Harpia harpyja) is threatened with extinction throughout its distribution in the neotropical forests. In the Atlantic Forest, deforestation has reduced the number of suitable habitats, with only a few remnant forest fragments hosting active nests; currently, the only known nests in this region are in the Central Atlantic Forest Ecological Corridor (CAFEC), in Brazil. Little is known about Harpy Eagle diets in this region, despite this information being essential for developing effective conservation strategies. We classified the composition, frequency, richness, ecological attributes, and conservation status of the species that make up the Harpy Eagle's diet in its last refuges in the CAFEC. Between 2017 and 2021, we collected and analyzed 152 prey remains and 285 camera trap photographs from seven active nests. We identified at least 16 mammal species (96.7%), one parrot and other bird remains (3.3%). The Harpy Eagle's diet consisted mainly of medium-sized arboreal, folivorous, frugivorous, and diurnal mammals. Five prey species are currently threatened with extinction at global, six at national and seven at regional levels. The majority of the diet consists of Sapajus robustus, which is threatened, and Bradypus variegatus, which is not threatened. In addition to the effects of habitat loss and hunting, the Harpy Eagle may also suffer from the decline in the populations of their prey in the Atlantic Forest.


Assuntos
Águias , Animais , Florestas , Ecossistema , Brasil , Árvores , Mamíferos
4.
Zookeys ; 1083: 109-128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35115874

RESUMO

A main priority in conservation is the protection of species in their natural habitat. However, ex situ management of threatened species is a recognised strategy of conservation. Harpy Eagles (Harpiaharpyja) are removed from the wild due to illegal capture, nest tree destruction, or other conflict sources. This study presents a review of the current ex situ Harpy Eagle populations in Brazil and worldwide, including information on the origin, sex, and year of entrance or year of birth under human care. Worldwide, until 2020 there were 205 Harpy Eagles in 77 different facilities in 16 countries, with 40 institutions in Brazil and 37 in other countries. The largest ex situ Harpy Eagle population is maintained in Brazil, with 139 individuals (75 females and 64 males) in 40 institutions. Of these institutions, there were 24 zoos, seven conservation breeding centres, six commercial breeders, two wildlife shelters, and one wildlife sorting centre. In Brazil, 62% (n = 86) of the individuals were hatched in the wild and 38% (n = 53) were bred in captivity under human care; for the wild individuals, only 73% (n = 64) have a known state of origin, with the majority from Pará state. This investigation provided relevant information to establish an ex situ demographic database. These individuals may potentially constitute a genetically and demographically viable safety population for future conservation strategies, as well as a source for research and education applied to Harpy Eagle integrated conservation.

5.
Ecol Evol ; 9(13): 7402-7409, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31346411

RESUMO

Road construction is considered to be one of the primary causes of forest fragmentation, and little is known about how roads affect bird reproductive success. The objective of this study was to assess the survival rate of artificial nests along an edge associated with a highway and in the interior of a tabuleiro forest. The study was performed at the Sooretama Biological Reserve, on the margins of federal highway BR-101, between September and October 2015. A total of 168 artificial nests with a Common quail (Coturnix coturnix) egg in each nest were placed along six sampling transects, at distances of 2, 25, 50, 100, 200, 400, and 800 m from the highway toward the forest interior. We used logistic regression and estimated daily survival rate (DSR) using the "Nest Survival" function in the program MARK to estimate artificial nest survival and assessed the effect of the distance from the highway. The artificial nest survival rate was significantly higher on the highway margins than at other distances. The results show that artificial nests located up to 25 m from the highway have a greater success probability (over 95%) and a significant decrease in success probability more than 50 m from the highway. Although we cannot rule out other nonroad-specific edge effects on artificial nest predation, our results suggest that the impacts of the highway (e.g., noise, vibration, visual stimuli) cause predators to avoid the road's surroundings (up to 25 m into the forest) when selecting their feeding sites, which partially supports the predation release hypothesis.

6.
Sci Total Environ ; 562: 542-549, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27110968

RESUMO

In most countries, the loss of biodiversity caused by the fires is worrying. In this sense, the fires detection towers are crucial for rapid identification of fire outbreaks and can also be used in environmental inspection, biodiversity monitoring, telecommunications mechanisms, telemetry and others. Currently the methodologies for allocating fire detection towers over large areas are numerous, complex and non-standardized by government supervisory agencies. Therefore, this study proposes and evaluates different methodologies to best location of points to install fire detection towers considering the topography, risk areas, conservation units and heat spots. Were used Geographic Information Systems (GIS) techniques and unaligned stratified systematic sampling for implementing and evaluating 9 methods for allocating fire detection towers. Among the methods evaluated, the C3 method was chosen, represented by 140 fire detection towers, with coverage of: a) 67% of the study area, b) 73.97% of the areas with high risk, c) 70.41% of the areas with very high risk, d) 70.42% of the conservation units and e) 84.95% of the heat spots in 2014. The proposed methodology can be adapted to areas of other countries.


Assuntos
Monitoramento Ambiental/métodos , Incêndios , Florestas , Sistemas de Informação Geográfica , Conservação dos Recursos Naturais , Árvores
7.
PLoS One ; 11(2): e0148902, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26871719

RESUMO

Habitat loss and fragmentation intensify the effects of genetic drift and endogamy, reducing genetic variability of populations with serious consequences for wildlife conservation. The Harpy Eagle (Harpia harpyja) is a forest dwelling species that is considered near threatened and suffers from habitat loss in the forests of the Neotropical region. In this study, 72 historical and current samples were assessed using eight autosomal microsatellite markers to investigate the distribution of genetic diversity of the Harpy Eagle of the Amazonian and Atlantic forests in Brazil. The results showed that the genetic diversity of Harpy Eagle decreased in the regions where deforestation is intense in the southern Amazon and Atlantic Forest.


Assuntos
Águias/genética , Floresta Úmida , Animais , Brasil , Espécies em Perigo de Extinção , Deriva Genética , Variação Genética , Repetições de Microssatélites
8.
PLoS One ; 10(8): e0134877, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26244644

RESUMO

Road mortality is the leading source of biodiversity loss in the world, especially due to fragmentation of natural habitats and loss of wildlife. The survey of the main species victims of roadkill is of fundamental importance for the better understanding of the problem, being necessary, for this, the correct species identification. The aim of this study was to verify if DNA barcodes can be applied to identify road-killed samples that often cannot be determined morphologically. For this purpose, 222 vertebrate samples were collected in a stretch of the BR-101 highway that crosses two Discovery Coast Atlantic Forest Natural Reserves, the Sooretama Biological Reserve and the Vale Natural Reserve, in Espírito Santo, Brazil. The mitochondrial COI gene was amplified, sequenced and confronted with the BOLD database. It was possible to identify 62.16% of samples, totaling 62 different species, including Pyrrhura cruentata, Chaetomys subspinosus, Puma yagouaroundi and Leopardus wiedii considered Vulnerable in the National Official List of Species of Endangered Wildlife. The most commonly identified animals were a bat (Molossus molossus), an opossum (Didelphis aurita) and a frog (Trachycephalus mesophaeus) species. Only one reptile was identified using the technique, probably due to lack of reference sequences in BOLD. These data may contribute to a better understanding of the impact of roads on species biodiversity loss and to introduce the DNA barcode technique to road ecology scenarios.


Assuntos
Animais Selvagens/genética , Código de Barras de DNA Taxonômico/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Florestas , Animais , Animais Selvagens/classificação , Brasil , Conservação dos Recursos Naturais/métodos , Geografia , Dados de Sequência Molecular , Reprodutibilidade dos Testes
9.
Genet. mol. biol ; 31(1): 146-154, 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-476165

RESUMO

We report the characterization and optimization of 45 heterologous microsatellite loci, and the development of a new set of molecular sex markers for the conservation and management of the Neotropical harpy eagle (Harpia harpyja L. 1758). Of the 45 microsatellites tested, 24 were polymorphic, six monomorphic, 10 uncharacterizable due to multiple bands and five did not amplify. The observed gene diversity of the analyzed sample of H. harpyja was low and similar to that of other threatened Falconiformes. While a high proportion of the microsatellite markers were highly variable, individuals of H. harpyja could be differentiated by a joint analysis of just three (p = 2.79 x 10-4) or four markers (p = 2.89 x 10-5). Paternity could be rejected with 95.23 percent and 97.83 percent probabilities using the same three and four markers, respectively. The sex determination markers easily and consistently differentiated males from females even with highly degraded DNA extracted from naturally shed feathers. The markers reported in this study potentially provide an excellent set of molecular tools for the conservation and management of wild and captive H. harpyja and they may also prove useful for the enigmatic Neotropical crested eagle (Morphnus guianensis Daudin 1800).


Assuntos
Animais , Águias/genética , Conservação dos Recursos Naturais , Repetições de Microssatélites , Variação Genética , Genética Populacional , Aves Predatórias , Fatores Sexuais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA