Relações ecológicas na distribuição de 25 espécies de vertebrados neotropicais em mesoescala

Vertebrates are a vital component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services (supporting, provision and cultural) they continue to be threatened by anthropogenic perturbations including hunting and habitat loss across the Amazon. Here we use a standardized regularly spaced arrangement within 25km2 to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. Camera traps were placed for 30 days during both dry and wet seasons at 30 points separated by 1km intervals along a pre-established trail system. Mann-Whitney U tests were used to examine seasonal differences in the per species encounters (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and in functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (Panthera onca) and Puma (Puma concolor)] and their prey. A total of 649 independent photos of 25 species were obtained from 1800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons in only three species (Mazama americana, Dasyprocta leporina and Myoprocta acouchy) all of which were photographed more (3 to 10 fold increase) during the wet season. M. americana was the only species where a significant difference was found in occupancy with more photos in more cameras during the wet season. For most groups and species our GLMs only weakly explained variation in the number of photos per camera (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (Crax alector, Psophia crepitans and Tinamus major) and rodents (Cuniculus paca, Dasyprocta leporina and M. acouchy) were the notable exceptions with our GLMs significantly explaining variation in the distribution of all species (deviance explained ranging from 21.0 to 54.5%). The group and species GLMs showed some novel ecological information from this relatively ―pristine area‖. In the case of groups we found no association between large cats and their potential prey. We also found that rodent and bird species were more often recorded closer to streams. As hunters gain access via rivers this finding suggests that there is currently little anthropogenic impact on the species. Our findings provide a standardized baseline for comparison with other sites and with which planned management and extractive activities can be evaluated.Os vertebrados são um componente vital da biodiversidade da floresta Amazônica. Apesar de serem uma parte importante da funcionalidade de vários serviços do ecossistema (suporte, reserva, cultural) continuam a ser ameaçados por perturbações antrópicas, incluindo caça e perda de habitat em toda a Amazônia. Aqui usamos um arranjo regularmente espaçado e padronizado dentro de uma área de 25 km², para fornecer uma avaliação inicial da diversidade de espécies de vertebrados em uma área protegida de uso sustentável na Amazônia brasileira oriental. Armadilhas fotográficas foram instaladas por 30 dias durante as estações seca e chuvosa, em 30 pontos separados por intervalos de um quilômetro ao longo de um sistema de trilhas pré-estabelecido. O teste de Mann-Whitney U foi usado para avaliar as diferenças sazonais no número de encontros por espécie (número de fotos por armadilha fotográfica e número de câmeras com fotos). Modelos Lineares Generalizados (GLMs) foram então usados para examinar a influência de cinco variáveis (altitude, abertura do dossel, área basal, distância até o rio de grande porte e distância até o rio de pequeno porte mais próximos) sobre o número de fotos por espécie e por grupos funcionais. GLMs também foram usados para examinar as relações entre grandes predadores [Jaguar (Panthera onca) e Puma (Puma concolor)] e as suas presas. Um total de 649 fotos independentes de 25 espécies foi obtido a partir de 1800 armadilhas-dia (900 em cada estação, chuvosa e seca). Somente ungulados e roedores mostraram diferenças sazonais significativas no número de fotos por câmera. O número de fotos variou entre as estações em apenas três espécies (Mazama americana, Dasyprocta leporina e Myoprocta acouchy), as quais foram fotografadas mais (3 a 10 vezes mais) durante a estação chuvosa. M. americana foi a única espécie em que uma diferença significativa foi encontrada em relação a ocupação, com mais fotos em mais câmeras durante a estação chuvosa. Para a maioria dos grupos e espécies, nossos GLMs tiveram pouco poder de explicação na variação no número de fotos por câmera (variando entre 10,3 e 54,4%). Aves terrestres (Crax alector, Psophia crepitans e Tinamus major) e roedores (Cuniculus paca, Dasyprocta leporina e M. acouchy) foram as exceções notáveis para os nossos GLMs, explicando de forma significativa a variação na distribuição de todas as espécies (variando entre 21,0 e 54,5% ). Os GLMs para os grupos e espécies mostraram algumas informações ecológicas interessantes a partir desta "área relativamente intocada". No caso dos grupos não foi encontrada associação entre grandes felinos e suas presas em potencial. Descobrimos também que espécies de roedores e aves foram os mais registrados mais perto de córregos. Como caçadores têm acesso principalmente pelos rios em florestas tropicais, estes dados sugerem que atualmente há pouco impacto antropogênico nestas espécies na área de estudo. Nossos resultados fornecem uma base padronizada para comparação com outras áreas, e com os quais é possível planejar atividades de gestão e extrativismo

Environmental determinants and use of space by six Neotropical primates in the northern Brazilian Amazon

<p>The Guiana Shield has large pristine tracts of tropical forest with high biological diversity and is an area of endemism within the Amazon Basin. However, the conservation status of primates in eastern Amazonian Brazil is still poorly known. Here, we report information on relative abundance, group size, density estimates, plus the effects of environmental variables and seasonality of primates in a sustainable-use reserve in the eastern Brazilian Amazon. From a 603 km transect-based census conducted in October–December 2013 and March–June 2014 we obtained 122 sighting records of six primate species. The most common were <i>Ateles paniscus</i> (45 detections) and <i>Saguinus midas</i> (40 detections). The high calculated density estimates for <i>Sg. midas</i> (2.01 groups/km² or 12.05 individuals/km²) and for <i>At. paniscus</i> (3.44 groups/km² or 10.31 individuals/km²) underscore the conservation importance of the study area for the vulnerable <i>At. paniscus</i>. We found no effect of environmental variables on the number of detections of primates, except for <i>At. paniscus</i> and <i>Cebus olivaceus</i>, with the former showing a higher number of detections in more open canopy forest during the rainy season, and the later having a higher number of detections in areas with higher density of palms in the dry season.</p

Ecological Relationships of Meso-Scale Distribution in 25 Neotropical Vertebrate Species

<div><p>Vertebrates are a vital ecological component of Amazon forest biodiversity. Although vertebrates are a functionally important part of various ecosystem services they continue to be threatened by anthropogenic impacts throughout the Amazon. Here we use a standardized, regularly spaced arrangement of camera traps within 25km² to provide a baseline assessment of vertebrate species diversity in a sustainable use protected area in the eastern Brazilian Amazon. We examined seasonal differences in the per species encounter rates (number of photos per camera trap and number of cameras with photos). Generalized linear models (GLMs) were then used to examine the influence of five variables (altitude, canopy cover, basal area, distance to nearest river and distance to nearest large river) on the number of photos per species and on functional groups. GLMs were also used to examine the relationships between large predators [Jaguar (<i>Panthera onca</i>) and Puma (<i>Puma concolor</i>)] and their prey. A total of 649 independent photos of 25 species were obtained from 1,800 camera trap days (900 each during wet and dry seasons). Only ungulates and rodents showed significant seasonal differences in the number of photos per camera. The number of photos differed between seasons for only three species (<i>Mazama americana</i>, <i>Dasyprocta leporina</i> and <i>Myoprocta acouchy</i>) all of which were photographed more (3 to 10 fold increase) during the wet season. <i>Mazama americana</i> was the only species where a significant difference was found in occupancy, with more photos in more cameras during the wet season. For most groups and species variation in the number of photos per camera was only explained weakly by the GLMs (deviance explained ranging from 10.3 to 54.4%). Terrestrial birds (<i>Crax alector</i>, <i>Psophia crepitans</i> and <i>Tinamus major</i>) and rodents (<i>Cuniculus paca</i>, <i>Dasyprocta leporina</i> and <i>M</i>. <i>acouchy</i>) were the notable exceptions, with our GLMs significantly explaining variation in the distribution of all species (deviance explained ranging from 21.0 to 54.5%). The group and species GLMs showed some novel ecological information from this relatively pristine area. We found no association between large cats and their potential prey. We also found that rodent and bird species were more often recorded closer to streams. As hunters gain access via rivers this finding suggests that there is currently little anthropogenic impact on the species. Our findings provide a standardized baseline for comparison with other sites and with which planned management and extractive activities can be evaluated.</p></div

Ecologia trófica do lobo-guará, Chrysocyon Brachyurus (Illiger, 1811), no Parque Estadual do Guartelá, Tibagi, PR, Brasil

O estudo do habito alimentar do lobo-guara no Parque Estadual do Guartela - PEG (Tibagi, Paraná, Brasil) foi realizado através da analise de 104 amostras de fezes coletadas entre agosto de 2011 e julho de 2012, sendo 70 delas (67,31%) coletadas no período chuvoso (outubro a fevereiro) e 34 (32,69%) nos meses mais secos (de marco a setembro). Foram identificados 11 itens alimentares, cinco de origem vegetal e que representaram 99,29% do total de recursos consumidos e seis de origem animal (0,71% do total de recursos). Entre os itens vegetais destacam-se os frutos de Syagrus romanzoffiana (jerivá) presentes em 10 dos 12 meses de amostragem, com uma frequência relativa de 66,89%; o mesmo ainda foi o item vegetal mais representativo em biomassa ingerida, correspondendo a 33,14% da biomassa total consumida. Entre os itens de origem animal, os roedores destacaram-se, estando presentes em oito meses da amostragem e com uma frequência relativa de 0,32%; porém os tatus foram os mais significativos em relação à biomassa ingerida, com 38,34% do total. Em relação às estacoes do ano, a de maior abundância de amostras foi o verão (49), seguida da primavera (36), outono (12) e inverno (7). O Índice de Levins (BA) como medida de amplitude de nicho resultou em valores baixos para todo o período amostrado (0,1047), indicando uma baixa equidistribuicao no uso de recursos, já em análise mensal, julho apresentou a maior amplitude (0,7009). Os resultados deste estudo confirmam que também no PEG o lobo-guará apresenta uma dieta generalista oportunista, alimentando-se principalmente de itens de origem vegetal, de acordo com a sua disponibilidade no ambiente

Number of independent photos (Detection), number of cameras that recorded photos (NCP) and relative abundance in dry and wet seasons of all vertebrate species examined in this study.

<p>^a Number of detections with independent photos.</p><p>^b Number of cameras that recorded photos of the species.</p><p>^c Average relative abundance (number of independent photos per 10 camera-trap days).</p><p>* Differences between seasons. Mann-Whitney test: ^†p <0.1, *p <0.05, **p<0.01, ***p<0.001.</p><p>Number of independent photos (Detection), number of cameras that recorded photos (NCP) and relative abundance in dry and wet seasons of all vertebrate species examined in this study.</p

Number of photos per sampling point for vertebrate species sampled on a 25 km² grid, Amapá National Forest, Brazil.

<p>(A) Galliformes; (B) Gruiformes; (C) Tinamiformes; (D) Artiodactyla; (E) Perissodactyla; (F) Carnivora; (G) Cingulata; (H) Rodentia.</p

Parameter (Slope) estimates from GLMs analysis of the abundance of vertebrate species in the eastern Brazilian Amazon.

<p>Significance values: ^†not significant, *p <0.05, **p<0.01, ***p<0.001.</p><p>^a Slope for variables and Standard Error (SE);</p><p>^b Percentage of Deviance Explained for each model (DE (%));</p><p>^c Akaike Information Criterion value for each model (AIC).</p><p>Parameter (Slope) estimates from GLMs analysis of the abundance of vertebrate species in the eastern Brazilian Amazon.</p

Location of the study region in the Amapá National Forest (ANF), Amapá State, eastern Brazilian Amazon.

<p>(A) Amapá State in Brazil; (B) ANF (red polygon) in Amapá State; (C) SRTM image showing altitude across the grid system (dotted lines) where the study was conducted. Camera traps were placed at 30 regularly spaced sample points (black triangles).</p

Cumulative curves for mammal and bird species sampled with camera traps in the dry and rainy seasons in the Amapá National Forest.

<p>Detection of species recorded in the 30 sample points is randomized 1000 times and results used to derive mean (dark blue line) 95% confidence intervals of the mean (light blue polygon). (A) Cumulative curve for mammal species in the dry season; (B) Cumulative curve for bird species in the dry season; (C) Cumulative curve for mammal species in the rainy season; (D) Cumulative curve for birds species in the rainy season.</p