Revista de Biologia Neotropical / Journal of Neotropical Biology
Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history informa... more Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history information in regard to other species, as also about survey methods used by field researchers. In this work we report the capture methodology implemented during population monitoring in northern Uruguay and some observations about defensive and feeding behaviours. We found the use of a metallic clamp as very useful for capturing juveniles and subadult individuals (< 120 cm total length) in vegetated habitats, while a wire snare was used for adults. Regardless locomotor escape, we provide a reappraisal of defensive behaviours in the presence of humans, with particular comments on tonic immobility. In addition, we suggest an apparent case of carcass consumption (scavenging) for the species, a presumedly common behaviour but sometimes hard to observe in wild crocodilians.
24th Irish Machine Vision and Image Processing Conference
Soundscape ecologists aim to study the acoustic characteristics of an area that reflects natural ... more Soundscape ecologists aim to study the acoustic characteristics of an area that reflects natural processes [Schafer, 1977]. These sounds can be interpreted as biological (biophony), geophysical (geophony), and human-produced (anthrophony) [Pijanowski et al., 2011]. A common task is to use sounds to identify species based on the frequency content of a given signal. This signal can be further converted into spectrograms enabling other types of analysis to automate the identification of species. Based on the promising results of deep learning methods, such as Convolution Neural Networks (CNNs) in image classification, here we propose the use of a pre-trained VGG16 CNN architecture to identify two nocturnal avian species, namely Antrostomus rufus and Megascops choliba, commonly encountered in Brazilian forests. Monitoring the abundance of these species is important to ecologists to develop conservation programmes, detect environmental disturbances and assess the impact of human action. ...
MotivationSIA‐BRA is a data set that compiles stable carbon (C) and nitrogen (N) isotope ratios o... more MotivationSIA‐BRA is a data set that compiles stable carbon (C) and nitrogen (N) isotope ratios of terrestrial and aquatic animals sampled in Brazilian biomes and coastal marine areas. Stable isotope ratios are helpful in animal ecology for several reasons; for instance, they can be used to investigate trophic niches, energy sources (diet tracing) and to track migration patterns. The Neotropics are considered one of the most undersampled regions of the world. Given that Brazil is a continental country where most of the dietary ecology of animal species is under‐assessed, we believe that the SIA‐BRA can provide important complementary information to address this gap in the literature. Additionally, the SIA‐BRA data set allows future investigations to address many questions concerning diet tracing, habitat use, food webs, foraging ecology, physiological aspects and effects of phylogeny on dietary ecology.Main type of variable investigatedCarbon and nitrogen stable isotope ratios for t...
Mammalian carnivores are considered a key group in maintaining ecological health and can indicate... more Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non‐detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non‐governmental organizations, and private consultants. Data were collected using several methods including camera trapping, muse...
Jaguars Panthera onca are absent from approximately 70% of the remaining Brazilian Atlantic Fores... more Jaguars Panthera onca are absent from approximately 70% of the remaining Brazilian Atlantic Forest due to a combination of habitat loss and degradation, poaching and high hunting pressure on their prey (Azevedo & Conforti, 2008; Galetti et al., 2013). This contrasts with North American and European large terrestrial predators that are recovering their historical abundance levels, colonizing even environments that are shaped by humans (Morrel, 2013; Chapron et al., 2014). Population supplementation and reintroduction programs, linked with hunting control, are proposed as management actions to reverse the jaguar’s fate (Galetti et al., 2013); however, a combination of agricultural landuse change and the introduction of an invasive exotic species – the wild boar Sus scrofa – might, paradoxically, have more of a positive effect. The state of São Paulo (Southeastern Brazil) hosts some of the largest protected remnants of Atlantic Forest, but in most of them jaguars are locally extinct. In the past two decades, large areas of relatively unproductive pasturelands, used for livestock grazing in this state, have been replaced by either sugarcane or Eucalyptus plantations. Such landuse change is directly impacting biodiversity (Verdade et al., 2012), but might benefit jaguars. The background of workers involved in these agro-industrial activities is changing from local residents to temporary workers coming from urban areas. The displaced locals are predominantly moving to the cities (Diaz-Chavez et al., 2015), losing their rural culture (Comin et al., 2009). It is, therefore, reasonable to expect that human hunting pressure on jaguars and their prey might decrease. In addition, the reduction of conflict with livestock, because of land-use change, is likely to decrease retaliation on jaguars. Wild boars are now widespread in the state of São Paulo (Pedrosa Salerno, 2015 et al., Eucalyptus and sugarcane plantations (Fig. 1). Jaguars are able to prey upon well-armed large animals such as caimans Caiman yacare and tapirs Tapirus terrestris (Azevedo & Verdade, 2012), making wild boar a potential prey. This combination of low hunting pressure and high prey abundance in these agricultural landscapes might increase the opportunity for jaguars to move over large distances, possibly connecting the remaining isolated populations of the species in the eastern and western regions of the state (respectively, ‘Serra do Mar’ and ‘Morro do Diabo’ State Parks). If this does occur, population expansion and connection might increase the jaguar population’s genetic variability, which is currently low (Haag et al., 2010). Although, paradoxically dependent on the introduction of a highly invasive exotic species and on the land-use change in agricultural landscapes, the recovery of a top predator is desirable from conservationists’ point of view, but it imposes challenges for the field of wildlife management. In such contexts, governance is crucial to mitigate the inevitable conflicts due to concerns about the security of agricultural workers, the potential increase in road accidents and the spread of diseases (e.g. rabies). In order to confront these challenges, the following issues need to be addressed: (1) wild boars are considered to be the most invasive vertebrate in the world (Barrios-Garcia & Ballari, 2012); the cost of their control could be considerably reduced in the presence of jaguars; (2) agricultural landscapes should be multifunctional with a primary mission of producing crops and domesticated livestock, but also a secondary mission of conserving wild species (Verdade et al., 2014); and last but not least, (3) capacity building in the field of wildlife management should be stimulated in Brazil (Verdade, 2004). Many countries have been facing conflicts related to the recovery of large predators (Marchini, 2014), and their experience would be invaluable in such a task. In addition, the following research questions might be addressed by conservation scientists in order to evaluate the feasibility of the future scenario posed in this letter: (1) What is the current jaguar carrying capacity of Eucalyptus and sugarcane agricultural landscapes in relation to the pris-
Revista de Biologia Neotropical / Journal of Neotropical Biology
Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history informa... more Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history information in regard to other species, as also about survey methods used by field researchers. In this work we report the capture methodology implemented during population monitoring in northern Uruguay and some observations about defensive and feeding behaviours. We found the use of a metallic clamp as very useful for capturing juveniles and subadult individuals (< 120 cm total length) in vegetated habitats, while a wire snare was used for adults. Regardless locomotor escape, we provide a reappraisal of defensive behaviours in the presence of humans, with particular comments on tonic immobility. In addition, we suggest an apparent case of carcass consumption (scavenging) for the species, a presumedly common behaviour but sometimes hard to observe in wild crocodilians.
24th Irish Machine Vision and Image Processing Conference
Soundscape ecologists aim to study the acoustic characteristics of an area that reflects natural ... more Soundscape ecologists aim to study the acoustic characteristics of an area that reflects natural processes [Schafer, 1977]. These sounds can be interpreted as biological (biophony), geophysical (geophony), and human-produced (anthrophony) [Pijanowski et al., 2011]. A common task is to use sounds to identify species based on the frequency content of a given signal. This signal can be further converted into spectrograms enabling other types of analysis to automate the identification of species. Based on the promising results of deep learning methods, such as Convolution Neural Networks (CNNs) in image classification, here we propose the use of a pre-trained VGG16 CNN architecture to identify two nocturnal avian species, namely Antrostomus rufus and Megascops choliba, commonly encountered in Brazilian forests. Monitoring the abundance of these species is important to ecologists to develop conservation programmes, detect environmental disturbances and assess the impact of human action. ...
MotivationSIA‐BRA is a data set that compiles stable carbon (C) and nitrogen (N) isotope ratios o... more MotivationSIA‐BRA is a data set that compiles stable carbon (C) and nitrogen (N) isotope ratios of terrestrial and aquatic animals sampled in Brazilian biomes and coastal marine areas. Stable isotope ratios are helpful in animal ecology for several reasons; for instance, they can be used to investigate trophic niches, energy sources (diet tracing) and to track migration patterns. The Neotropics are considered one of the most undersampled regions of the world. Given that Brazil is a continental country where most of the dietary ecology of animal species is under‐assessed, we believe that the SIA‐BRA can provide important complementary information to address this gap in the literature. Additionally, the SIA‐BRA data set allows future investigations to address many questions concerning diet tracing, habitat use, food webs, foraging ecology, physiological aspects and effects of phylogeny on dietary ecology.Main type of variable investigatedCarbon and nitrogen stable isotope ratios for t...
Mammalian carnivores are considered a key group in maintaining ecological health and can indicate... more Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non‐detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non‐governmental organizations, and private consultants. Data were collected using several methods including camera trapping, muse...
Jaguars Panthera onca are absent from approximately 70% of the remaining Brazilian Atlantic Fores... more Jaguars Panthera onca are absent from approximately 70% of the remaining Brazilian Atlantic Forest due to a combination of habitat loss and degradation, poaching and high hunting pressure on their prey (Azevedo & Conforti, 2008; Galetti et al., 2013). This contrasts with North American and European large terrestrial predators that are recovering their historical abundance levels, colonizing even environments that are shaped by humans (Morrel, 2013; Chapron et al., 2014). Population supplementation and reintroduction programs, linked with hunting control, are proposed as management actions to reverse the jaguar’s fate (Galetti et al., 2013); however, a combination of agricultural landuse change and the introduction of an invasive exotic species – the wild boar Sus scrofa – might, paradoxically, have more of a positive effect. The state of São Paulo (Southeastern Brazil) hosts some of the largest protected remnants of Atlantic Forest, but in most of them jaguars are locally extinct. In the past two decades, large areas of relatively unproductive pasturelands, used for livestock grazing in this state, have been replaced by either sugarcane or Eucalyptus plantations. Such landuse change is directly impacting biodiversity (Verdade et al., 2012), but might benefit jaguars. The background of workers involved in these agro-industrial activities is changing from local residents to temporary workers coming from urban areas. The displaced locals are predominantly moving to the cities (Diaz-Chavez et al., 2015), losing their rural culture (Comin et al., 2009). It is, therefore, reasonable to expect that human hunting pressure on jaguars and their prey might decrease. In addition, the reduction of conflict with livestock, because of land-use change, is likely to decrease retaliation on jaguars. Wild boars are now widespread in the state of São Paulo (Pedrosa Salerno, 2015 et al., Eucalyptus and sugarcane plantations (Fig. 1). Jaguars are able to prey upon well-armed large animals such as caimans Caiman yacare and tapirs Tapirus terrestris (Azevedo & Verdade, 2012), making wild boar a potential prey. This combination of low hunting pressure and high prey abundance in these agricultural landscapes might increase the opportunity for jaguars to move over large distances, possibly connecting the remaining isolated populations of the species in the eastern and western regions of the state (respectively, ‘Serra do Mar’ and ‘Morro do Diabo’ State Parks). If this does occur, population expansion and connection might increase the jaguar population’s genetic variability, which is currently low (Haag et al., 2010). Although, paradoxically dependent on the introduction of a highly invasive exotic species and on the land-use change in agricultural landscapes, the recovery of a top predator is desirable from conservationists’ point of view, but it imposes challenges for the field of wildlife management. In such contexts, governance is crucial to mitigate the inevitable conflicts due to concerns about the security of agricultural workers, the potential increase in road accidents and the spread of diseases (e.g. rabies). In order to confront these challenges, the following issues need to be addressed: (1) wild boars are considered to be the most invasive vertebrate in the world (Barrios-Garcia & Ballari, 2012); the cost of their control could be considerably reduced in the presence of jaguars; (2) agricultural landscapes should be multifunctional with a primary mission of producing crops and domesticated livestock, but also a secondary mission of conserving wild species (Verdade et al., 2014); and last but not least, (3) capacity building in the field of wildlife management should be stimulated in Brazil (Verdade, 2004). Many countries have been facing conflicts related to the recovery of large predators (Marchini, 2014), and their experience would be invaluable in such a task. In addition, the following research questions might be addressed by conservation scientists in order to evaluate the feasibility of the future scenario posed in this letter: (1) What is the current jaguar carrying capacity of Eucalyptus and sugarcane agricultural landscapes in relation to the pris-
Highlights
●● Biodiversity resources are unevenly distributed across the globe. As a consequence
... more Highlights ●● Biodiversity resources are unevenly distributed across the globe. As a consequence of the asymmetrical geographic distribution of species, any consideration of the impacts of biofuels on biodiversity is likely to be biome, site and context specific. Land transformation is the most serious threat to biodiversity, and the rapid expansion of biofuels crops, most especially sugarcane and palm oil in the tropics, is currently the most serious of these concerns. Thus effects of biofuel feedstock production on biodiversity and ecosystem services are context specific, and location-specific management of biofuel feedstock production systems should be implemented to maintain biodiversity and ecosystem services. ●● Few positive influences on biodiversity and ecosystem services result from biofuels development. Such positive outcomes are of limited spatial and taxonomic scale. Biofuels-mediated improvements can occur when already degraded lands are rehabilitated with non-native feedstocks, but such changes in habitat structure and ecosystem function support few and mostly common species of native flora and fauna. Even the limited evidence of perennial grass crops favoring certain bird species indicates the requirement of special management regimes. ●● Trade-offs between biofuels and environmental resources are inevitable. The mitigation of climate change via reducing GHG emissions through a transition to low carbon energy systems such as selected biofuels offers a logical trade-off, as long as the design of expanded biofuel production avoids areas of special biodiversity concerns or embeds new production areas within a sustainable matrix of natural and transformed ecosystems. ●● Available land resources exceed the projected needs for biodiversity conservation in terms of both the Convention on Biological Diversity target of Protected Area system expansion to 17% of the global terrestrial area and biofuels expansion to several fold current production levels. ●● Sustainable biofuels and biodiversity management requires cross-sectoral integrated planning and regular monitoring of selected, cost effective and policy relevant indicators. Cost effective, landscape-level biodiversity indicators are in development but await application over most of the developing world.
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Papers by Luciano Verdade
●● Biodiversity resources are unevenly distributed across the globe. As a consequence
of the asymmetrical geographic distribution of species, any consideration of the
impacts of biofuels on biodiversity is likely to be biome, site and context specific.
Land transformation is the most serious threat to biodiversity, and the rapid
expansion of biofuels crops, most especially sugarcane and palm oil in the tropics,
is currently the most serious of these concerns. Thus effects of biofuel feedstock
production on biodiversity and ecosystem services are context specific, and
location-specific management of biofuel feedstock production systems should be
implemented to maintain biodiversity and ecosystem services.
●● Few positive influences on biodiversity and ecosystem services result from biofuels
development. Such positive outcomes are of limited spatial and taxonomic scale.
Biofuels-mediated improvements can occur when already degraded lands are
rehabilitated with non-native feedstocks, but such changes in habitat structure
and ecosystem function support few and mostly common species of native flora
and fauna. Even the limited evidence of perennial grass crops favoring certain
bird species indicates the requirement of special management regimes.
●● Trade-offs between biofuels and environmental resources are inevitable. The
mitigation of climate change via reducing GHG emissions through a transition to
low carbon energy systems such as selected biofuels offers a logical trade-off,
as long as the design of expanded biofuel production avoids areas of special
biodiversity concerns or embeds new production areas within a sustainable
matrix of natural and transformed ecosystems.
●● Available land resources exceed the projected needs for biodiversity conservation
in terms of both the Convention on Biological Diversity target of Protected Area
system expansion to 17% of the global terrestrial area and biofuels expansion to
several fold current production levels.
●● Sustainable biofuels and biodiversity management requires cross-sectoral
integrated planning and regular monitoring of selected, cost effective and policy
relevant indicators. Cost effective, landscape-level biodiversity indicators are in
development but await application over most of the developing world.