29 research outputs found
Influence of the vegetation mosaic on ant (Formicidae: Hymenoptera) distributions in the Northern Brazilian Pantanal
We examined how vegetation mosaic influences distribution of the edaphic ant (Formicidae) community in the northern part of the Pantanal in Cáceres, State of Mato Grosso, Brazil. Plant formations (hereafter habitats) that characterize this area include several savanna types, such as: Cerrado sensu stricto, Cerradão, Semi-deciduous forest, Termite savanna, Open fields and Cerrado field/carandazal. Pitfall traps were placed in ten 250 m transects each one separated by 1 km, within an area of 2 x 5 km (following RAPELD methodology). Five traps at intervals of 50 m were placed along each transect, in September and December 2008. Forty-four ant species were collected. leaf litter predicted ant presence and influenced species occurrence in the different habitats. Pantanal habitats are very different structurally from one to another, which has have resulted in areas with very specific ant assemblages. The understanding of the antcommunity structure in these areas is fundamental to floodplain management
Canopy Ant Assemblage (Hymenoptera: Formicidae) in Two Vegetation Formations in the Northern Brazilian Pantanal
The landscape of the northern Pantanal region is a mosaic of fields and forests, distributed according to topography and hydrology of this floodplain, resulting in a particular pattern of vegetation distribution. Among the forest formations, mixedspecies and monodominant landscape units can be found which are associated with floodable or non-floodable habitats. Our study tested the hypothesis that forest formations with greater tree richness and which are non floodable (cordilheiras) maintain distinct richness and composition in canopy ant assemblages in relation to the seasonally floodable monodominant forests (cambarazais). Sampling was performed in 10 sample areas (five cambarazais and five cordilheiras) by means of canopy insecticide fogging during the dry and high water seasons of the Pantanal’s hydrological cycle. The canopy ant assemblages revealed 105 species belonging to 30 genera and nine subfamilies. Myrmicinae (41 spp.), Formicinae (20 spp.) and Pseudomyrmecinae (17 spp.) predominated. Our results revealed that the composition of canopy ant assemblages varied between cambarazal and cordilheira forests, as well as between the dry and high water periods. Nevertheless, the richness was homogeneous between these forests and in the dry and high water periods. These results show the specificity of each forest, as well as its structure, in maintaining distinct compositions in ant assemblages in canopies in the Pantanal of Mato Grosso
The importance of acoustic background modelling in CNN-based detection of the neotropical White-lored Spinetail (Aves, Passeriformes, Furnaridae)
Machine learning tools are widely used in support of bioacoustics studies, and there are numerous publications on the applicability of convolutional neural networks (CNNs) to the automated presence-absence detection of species. However, the relation between the merit of acoustic background modelling and the recognition performance needs to be better understood. In this study, we investigated the influence of acoustic background substance on the performance of the acoustic detector of the White-lored Spinetail (Synallaxis albilora). Two detector designs were evaluated: the 152-layer ResNet with transfer learning and a purposely created CNN. We experimented with acoustic background representations trained with season-specific (dry, wet, and all-season) data and without explicit modelling to evaluate its influence on the detection performance. The detector permits monitoring of the diel behaviour and breeding time of White-lored Spinetail solely based on the changes in the vocal activity patterns. We report an advantageous performance when background modelling is used, precisely when trained with all-season data. The highest classification accuracy (84.5%) was observed for the purposely created CNN model. Our findings contribute to an improved understanding of the importance of acoustic background modelling, which is essential for increasing the performance of CNN-based species detectors.This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brazil (CAPES) under Grant [CAPES-01]; Instituto Nacional de Ciência e Tecnologia em Áreas Úmidas (INAU/UFMT/CNPq); Centro de Pesquisa do Pantanal (CPP); and Brehm Funds for International Bird Conservation (BF), Germany
Fatores de caracterização da educação não formal: uma revisão da literatura
Resumo O presente artigo relata os resultados de uma investigação de caráter documental, na área da educação não formal. A educação não formal é uma área em expansão, à qual tem sido dada crescente atenção e importância. No entanto, é um setor do conhecimento, em geral, mal definido e ambíguo, no sentido em que os termos empregados são polissêmicos e não há consenso sobre seus usos e definições. Assim, com o objetivo de clarificar as definições das diferentes tipologias educativas, incluindo a educação não formal, perguntamos: que características têm estas tipificações educativas? Que critérios ou fatores são utilizados na literatura para defini-las? Com vista a responder a estas questões de pesquisa, realizamos uma revisão da literatura, analisando 28 documentos, entre literatura nacional e internacional, valendo-nos de técnicas de análise documental e análise de conteúdo. Apuramos que, na maioria da literatura nacional, a terminologia educação formal – não formal – informal é a mais utilizada. Confirmamos a dificuldade em se definir e estabelecer fronteiras entre as diferentes tipologias educativas e sublinhamos que as definições das mesmas envolvem um número elevado de fatores de diferentes naturezas. Investigamos 21 fatores usados nas caracterizações das diferentes tipologias educativas, divididos por quatro dimensões de análise: estrutura, processos, propósitos e conteúdos. Apuramos que, apesar da diversidade de fatores utilizados nas definições, há um núcleo adotado com mais frequência, associado principalmente a características estruturais, como localização, grau de planejamento ou duração da aprendizagem
Passive acoustic monitoring of the Ferruginous Pygmy-Owl (Glaucidium brasilianum) over a complete annual cycle: seasonality and monitoring recommendations
Monitoring the vocal behavior of owls is challenging because of their nocturnal habits and limited vocal activity. Here, we evaluated the use of passive acoustic monitoring coupled with automated signal recognition software to monitor the spontaneous vocal activity of the Ferruginous Pygmy-Owl (Glaucidium brasilianum) over a complete annual cycle at five recording stations in the Brazilian Pantanal. The vocal behavior of this species was concentrated during the crepuscular periods, with highest vocal activity in the hours prior to sunrise. The Ferruginous Pygmy-Owl was vocally active throughout the year, but the species showed a peak of activity from June to August. Paired Ferruginous Pygmy-Owl males tend to perform territorial calls less often during the nestling period, which may partly explain the significant decrease in the vocal activity after August. Our results suggest that the breeding period of the species starts in June, and the nesting phase probably occurs from September onwards, when the wet season starts. The first rains in seasonal tropical areas are usually associated with an increase in food availability, which may explain the species´ breeding period onset. Future surveys aiming to monitor the species, avoiding the use of broadcast calls, should be performed before sunrise between June and August, when the vocal activity was maximal
Diversity of Insect Flower Visitors of <i>Xylopia aromatica</i> (Magnoliales, Annonaceae) in a Brazilian Savanna
Small beetles are important pollinators of Annonaceae whose flower chambers are small and have diurnal and/or nocturnal anthesis. The pollinators of these flowers belong to the families Nitidulidae, Staphylinidae, Chrysomelidae, and Curculionidae. In this study, the first conducted in the Cerrado of Chapada dos Guimarães, Mato Grosso, Brazil, the behavior of the insect flower visitors of Xylopia aromatica was observed, in both the field and the laboratory. The chambers of 253 flowers were collected from 11 plants, and the biological aspects of their visitors were analyzed quantitatively and qualitatively. The most abundant visitors were thrips and beetles. Coleoptera was represented by four morphospecies occurring frequently in the floral chambers (>70% of individuals). Among beetles, one species belonged to Nitidulidae (Cillaeinae, Conotelus sp. 1) and two belonged to Staphylinidae (Aleocharinae sp. 1 and Aleocharinae sp. 2). These three morphospecies of small elongate beetles have setae where pollen may adhere. In addition, they were present on both male and female phases of the flowers, indicating potential cross-pollination. In the study area, X. aromatica possesses mixed pollination promoted by Thysanoptera and small Nitidulidae and Staphylinidae beetles. This study brings the first record of Lamprosomatinae (Chrysomelidae) and, especially, of Conotelus (Nitidulidae) in the flower chambers of X. aromatica, with new information on behavior of floral visitors coupled with their morphological traits that may promote cross-pollination in this plant species
Spatial and Temporal Adaptations of Lowland Tapirs (<i>Tapirus terrestris</i>) to Environmental and Anthropogenic Impacts
The Pantanal is one of the most conserved wetland ecosystems in Brazil and a hotspot for biodiversity. Over the last decades intensification of human activities has become a major threat to the stability of the unique landscape. To establish effective conservation actions, it is essential to understand how species respond to anthropogenic and environmental regional factors. Here, data from two multiannual camera trap studies, one in the northern Pantanal and one in the southern Pantanal, were used to investigate the effects of habitat characteristics, seasons, and human interactions on the spatial and temporal patterns of lowland tapirs (Tapirus terrestris). Between 2010 and 2017, camera traps were repeatedly placed in consistent grids covering protected areas and areas with cattle-ranching and tourism. Data were analyzed using generalized linear mixed models and circular statistics. Activity patterns were similar and predominantly nocturnal in both areas, but tapirs indicated avoidance toward settlements and cattle and indicated habitat preferences only in the northern study area with less anthropogenic activities. The present study suggests that both environmental and anthropogenic factors can affect the species’ spatial and temporal behavior, but tapirs show varying responses across regions and gradients of disturbance. The results indicate that adapting avoidance strategies might be more likely and effective in areas with low human pressure and sufficient protected areas as alternatives
Vanellus chilensis dataset accompanying PLOS ONE paper "Automated Sound Recognition Provides Insights into the Behavioral Ecology of a Tropical Bird"
Southern Lapwing Vanellus chilensis dataset accompanying the PLOS ONE article
O. Jahn, T. Ganchev, M.I. Marinez and K.L. Schuchmann: Automated Sound Recognition Provides Insights into the Behavioral Ecology of a Tropical Bird. DOI:10.1371/journal.pone.0169041
---
BL01:
Background Library 01 consists of
BL01 >> BL_CHVACH_free_final:
54 hand-cleaned (Vanellus chilensis-free) background files and
BL01 >> PSC008_forest:
36 original soundscapes recorded inside forest, which may contain a few target signals from overflying lapwings.
---
PONE_VACH_AnnualCycle_Statistics:
Contains the Excel files
- 2013CHVACH_BreedingCycle_Statistics_PONE: statistics on V. chilensis activity patterns, Apr. 2013 to Sep. 2013.
- 2013CHVACH_FalseNegatives_PONE: determination of the false negative rate based on an expert-annotated sample of 26 soundcsape recordings
- 2013CHVACH_FalsePositives_PONE: determination of the false positive rate based on an expert-annotated random sample of 1250 automated V. chilensis detections.
---
TL01_BIAVCHCHVACH_20130813v2_HandCleaned:
Training library for the development of the V. chilensis recognizer, consisting of 90 hand-filtered recordings of the target species.
---
VACH_Detector_results >> VACHdetectorOutput_PONE.zip:
TXT detector output files, listing timestamps of potential V. chilensis sound events.
---
VACH_FNrate_20160706:
Validation library used to determine the false negative rate. The library consists of 26 expert-annotated sound files. Annotations were made in Adobe Audion v3.0.
---
VL01_VACH_MonoB
and
VL01_VACH_MonoB:
Validation library used for the fine-tuning of the recognizer settings.
---
Important notes on the annotation of the VACH_FNrate_20160706 library:
1) In general, we used the procedure described in Ganchev et al. 2015 for the annotation of VACH validation libraries (see next section).
2) However, the detector-generated timestamps were not changed! For the following reasons, it is not possible to use the VACH_FN_rate library as a validation library for the development of improved recognizer versions:
(a) The VACH detector overlooked many of the weaker signals within a VACH call series. Therfore the detector-generated annotations are incomplete.
(b) For the same reason some automatically-generated detections may refer to a single VACH call event (double hits).
Details on the method used for the annotation of the VACH validation libraries are described in Ganchev et al. 2015, pp.6100f: 2.1.3.3.Vanellus chilensis validation dataset
Influence of the vegetation mosaic on ant (Formicidae: Hymenoptera) distributions in the Northern Brazilian Pantanal
We examined how vegetation mosaic influences distribution of the edaphic ant (Formicidae) community in the northern part of the Pantanal in Cáceres, State of Mato Grosso, Brazil. Plant formations (hereafter habitats) that characterize this area include several savanna types, such as: Cerrado sensu stricto, Cerradão, Semi-deciduous forest, Termite savanna, Open fields and Cerrado field/carandazal. Pitfall traps were placed in ten 250 m transects each one separated by 1 km, within an area of 2 x 5 km (following RAPELD methodology). Five traps at intervals of 50 m were placed along each transect, in September and December 2008. Forty-four ant species were collected. leaf litter predicted ant presence and influenced species occurrence in the different habitats. Pantanal habitats are very different structurally from one to another, which has have resulted in areas with very specific ant assemblages. The understanding of the antcommunity structure in these areas is fundamental to floodplain management