Helder Farias Pereira de Araujo

Dr. Helder Farias Pereira de Araujo


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2010 in Revista Brasileira de Entomologia
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AVAlexandre Vasconcellos
Alexandre Vasconcellos
RARicardo Andreazze
Ricardo Andreazze
AAAdriana M. Almeida
Adriana M. Almeida
HAHelder Farias Pereira de Araujo
Helder Farias Pereira de Araujo
EOEduardo S. Oliveira
Eduardo S. Oliveira
UOUirandé Oliveira
Uirandé Oliveira
Insects are essential to tropical ecosystems functioning. In semi-arid regions, the increase in abundance and/or activity (e.g. reproduction and foraging behavior) of insects is usually associated with climatic variables. The present study investigates which climatic variables are best predictors of insect abundance in an area of Caatinga in northeastern Brazil. Individuals were sampled for 24 months using Malaise and pitfall traps, and beating trays. A total of 58925 individuals belonging to 20 insect orders were collected. The most abundant orders were Hymenoptera, Diptera, Collembola and Coleoptera. Most orders studied showed a clear maximum abundance in the rainy season. Rainfall and humidity were the best predictors of insect abundance in the Caatinga. However, no climatic variable could explain Psocoptera and Blattodea variance in abundance/activity. Our results suggest that climatic changes associated with rainfall patterns in the Caatinga may affect ecosystem processes and services that depend direct or indirectly on insect abundance/activity. Os insetos são abundantes e essenciais para o funcionamento dos ecossistemas terrestres tropicais. No entanto, a abundância e/ou atividade (e.g. reprodução ou forrageio) destes organismos podem ser fortemente influenciadas pelas variáveis climáticas. Este estudo examina quais as variáveis climáticas podem atuar como preditoras da abundância e/ou atividade dos insetos em uma área de Caatinga do Nordeste brasileiro. Ao longo de 24 meses, os insetos foram coletados mensalmente utilizando armadilhas Malaise, armadilhas tipo "pitfall" e guarda-chuva entomológico. Um total de 58925 indivíduos de 20 ordens foi coletado. As ordens mais abundantes foram Hymenoptera, Diptera, Collembola e Coleoptera. Entre as doze ordens mais abundantes, dez apresentaram os seus maiores picos durante a estação chuvosa. A precipitação e a umidade relativa foram os principais preditores dos padrões de abundância e/ou atividade dos insetos na caatinga. Nenhuma variável climática foi relacionada com o número de indivíduos coletados de Psocoptera e Blattodea. Os efeitos das variáveis climáticas sobre os insetos sugerem que alterações no clima da caatinga, especialmente em seu padrão de precipitação, podem afetar os serviços ecossistêmicos que dependem direta e indiretamente da abundância e/ou atividade destes organismos

16 July 2012 in Bird Conservation International
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RARômulo Romeu Nóbrega Alves
Rômulo Romeu Nóbrega Alves
JLJosé Ribamar DE Farias Lima
José Ribamar DE Farias Lima
HAHelder Farias Pereira de Araujo
Helder Farias Pereira de Araujo
Summary: Brazil’s rich biological and cultural diversity makes it an exceptional location for examining the commerce in live wild birds and its implications for conservation. This paper catalogues the live bird species being traded in Brazil, characterises the trade in these animals, and discusses the implications for avian conservation. In spite of being illegal, capturing and selling birds is still a very common practice in Brazil and involves many actors who make up part of a large commercial network that distributes wild animals to every corner of the country. Our survey revealed that at least 295 bird species are illegally sold as pets in Brazil, with estimates derived from this data pointing to a total of more than 400 species - about 23% of the number of extant bird species in the country. Of the bird species recorded, two were classified as “Critically Endangered”, nine as “Endangered”, six as “Vulnerable”, and 19 as “Near Threatened” according to the most recent IUCN Red List. Most of the species recorded in this study as being widely bought and sold (including on the international market) are not listed by CITES even though many of them are in fact threatened. In light of the widespread illegal trade in wild birds in Brazil and the conservation implications for the species involved, there is an urgent need for actions that can control these activities. Steps should be taken to address the illegal traffic directly and these must include monitoring, law enforcement, effective sentencing (including deterrent sentences), targeting end-users, captive breeding, and education at all levels, taking into account the cultural, economic, social, and ecological aspects of the human populations involved.

11 November 2009 in Human Ecology
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Journal Article
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RARômulo Romeu Nóbrega Alves
Rômulo Romeu Nóbrega Alves
ENEmerina E. G. Nogueira
Emerina E. G. Nogueira
HAHelder Farias Pereira de Araujo
Helder Farias Pereira de Araujo
SBSharon E. Brooks
Sharon E. Brooks

27 October 2023 in Scientific Reports
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Journal Article
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HAHelder Farias Pereira de Araujo
Helder Farias Pereira de Araujo
NCNathália F. Canassa
Nathália F. Canassa
CMCélia C. C. Machado
Célia C. C. Machado
MTMarcelo Tabarelli
Marcelo Tabarelli
Drastic changes in vegetation structure caused by exceeding ecological thresholds have fueled the interest in tropical forest responses to climate and land-use changes. Here, we examine the potential successional trajectories experienced by the largest dry tropical forest region in South America, driven by climate conditions and human disturbance. We built potential distribution models for vertebrate taxa associated with forest or shrub habitats to estimate natural vegetation cover. Distribution patterns were compared to current vegetation across the entire region to identify distinct forest degradation levels. Our results indicate the region has climatic and soil conditions suitable for more forest cover than is currently found, even in some areas with limited precipitation. However, 11.04% of natural cover persists across such an immense region, with only 4.34% consisting of forest cover. Forest degradation is characterized by the dramatic expansion of shrubland (390%), farming, and non-vegetation cover due to changes in land-use, rather than climatic conditions. Although different climate conditions have been the principal drivers for natural forest distribution in the region, the forest seems unable to resist the consequences of land-use changes, particularly in lower precipitation areas. Therefore, land-use change has exceeded the ecological thresholds for the persistence of forests, while climate change may exacerbate vegetation-type transitions.

7 March 2019 in Ecology
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Journal Article
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RRRodolpho Credo Rodrigues
Rodolpho Credo Rodrigues
ÉHÉrica Hasui
Érica Hasui
JAJulia Camara Assis
Julia Camara Assis
JPJoão Carlos Pena
João Carlos Pena
RMRenata Lara Muylaert
Renata Lara Muylaert
ACANA COR
ANA COR
Scientists have long been trying to understand why the Neotropical region holds the highest diversity of birds on Earth. Recently, there has been increased interest in morphological variation between and within species, and in how climate, topography, and anthropogenic pressures may explain and affect phenotypic variation. Because morphological data are not always available for many species at the local or regional scale, we are limited in our understanding of intra‐ and interspecies spatial morphological variation. Here, we present the ATLANTIC BIRD TRAITS, a data set that includes measurements of up to 44 morphological traits in 67,197 bird records from 2,790 populations distributed throughout the Atlantic forests of South America. This data set comprises information, compiled over two centuries (1820–2018), for 711 bird species, which represent 80% of all known bird diversity in the Atlantic Forest. Among the most commonly reported traits are sex (n = 65,717), age (n = 63,852), body mass (n = 58,768), flight molt presence (n = 44,941), molt presence (n = 44,847), body molt presence (n = 44,606), tail length (n = 43,005), reproductive stage (n = 42,588), bill length (n = 37,409), body length (n = 28,394), right wing length (n = 21,950), tarsus length (n = 20,342), and wing length (n = 18,071). The most frequently recorded species are Chiroxiphia caudata (n = 1,837), Turdus albicollis (n = 1,658), Trichothraupis melanops (n = 1,468), Turdus leucomelas (n = 1,436), and Basileuterus culicivorus (n = 1,384). The species recorded in the greatest number of sampling localities are Basileuterus culicivorus (n = 243), Trichothraupis melanops (n = 242), Chiroxiphia caudata (n = 210), Platyrinchus mystaceus (n = 208), and Turdus rufiventris (n = 191). ATLANTIC BIRD TRAITS (ABT) is the most comprehensive data set on measurements of bird morphological traits found in a biodiversity hotspot; it provides data for basic and applied research at multiple scales, from individual to community, and from the local to the macroecological perspectives. No copyright or proprietary restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications or teaching and educational activities.

1 January 2017
Verified
Book Chapter
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HAHelder Farias Pereira de Araujo
Helder Farias Pereira de Araujo
JSJosé Maria Cardoso da Silva
José Maria Cardoso da Silva