Dieta de Didelphis aurita e Micoureus paraguayanus e a disponibilidade de frutos em uma floresta Atlantica semidecidual no sul do Brasil

This study analysed the effects of diets and resource partitioning among Didelphis aurita and Micoureus paraguayanus, and their relationships with food availability in a semideciduous Atlantic Forest of southern Brazil. Species were separated by sex, age and reproductive condition to compare with dietary data. The fruit availability in the area was quantified bimonthly through collection of fleshy fruits and flowers available on the ground of the study area. Individuals of D. aurita trapped in the canopy vs. those trapped on the ground, or even regarding age and sex classes, did not differ in regards to their diet composition. Animals studied were heterogeneous in relation to their diet composition, being significantly different from each other (p = 0.03). The largest diversity indexes observed for both species in faeces and in the environment occurred during the rainy season. Both species presented insects in their diets, but with natural tendency to consume fruits or vertebrates (D. aurita). Rhythms of fructification of Piper sp. correlated with consumption by D. aurita (rs = 0.90, p = 0.03) and not by M. paraguayanus (rs = 0.40, p = 0.60). There were tendencies where independent young and lactiferous females of D. aurita correlated to the peaks of fruit availability during the rainy season.Key words: mammals, Didelphidae, resource availability, vertical strata, food habit.Foi analisado o efeito da dieta e partilha de recursos entre Didelphis aurita e Micoureus paraguayanus, e suas relações com a disponibilidade de alimentos em uma floresta Atlantica semidecidual do sul do Brasil. As espécies foram separadas por sexo, idade e condições reprodutivas para comparar com dados da dieta. A disponibilidade de frutos na área foi quantificada bimestralmente através da coleta de frutos carnosos e flores disponíveis no solo da área de estudo. Indivíduos de D. aurita capturados no dossel vs. capturados no solo, ou mesmo os que diferem em idade e sexo, não diferem no que diz respeito a composição da dieta. Em relação a composição da dieta, os animais estudados eram heterogêneos, sendo significativamente diferentes entre si (p = 0,003). Os maiores índices de diversidade observados nas fezes de ambas as espécies ocorreram durante a estação de chuva. Ambas espécies apresentaram insetos em suas dietas, mas com tendências naturais ao consumo de frutos ou vertebrados (D. aurita). Ritmos de frutificação de Piper sp. correlacionaram-se com o consumo por D. aurita (rs = 0.90, p = 0.03) e não por M. paraguayanus (rs = 0.40, p = 0.60). Houve tendências onde jovens independentes e fêmeas lactantes de D. aurita correlacionaram com os picos de disponibilidade de frutos disponíveis durante a estação chuvosa.Palavras-chave: mamíferos, Didelphidae, disponibilidade de recursos, estrato vertical, hábito alimentar

Dieta de quatro espécies de pequenos mamíferos em fragmentos de floresta atlântica no sul do Brasil

In this study we analyse the diet composition of small mammals of western Paraná state, southern Brazil. Species studied were mostly unknown on feeding habits. Animals were sampled during the faunal survey carried out in October 1998 when implementing the Salto Caxias dam. The diet composition, based on gut contents, seems to be mostly opportunistic and generalist for the three marsupials, Micoureus paraguayanus, Caluromys lanatus, and Monodelphis sorex, and for the rodent, Akodon paranaensis, studied. Caeca of the four small mammal species had in general a small quantity of insects when compared with other digestive tract portions. However, when volume consumed was evaluated, Arthropoda was the most important item for three species of them. Inversely, fruits were important for C. lanatus. The estimated amount of plant material (seeds and other plant structures) had a higher importance for C. lanatus, mainly for caecum samples, however these items were also found in the other mammal species samples but in lower proportions. The high proportion of intact seeds on both, digestive tract and caecum, when compared with predated seeds, is noticeable, suggesting that the species are seed dispersal. Monodelphis sorex seems to have a more insectivorous diet, as it is a small cursorial mammal, although there was also evidence for frugivory or carnivory. Akodon paranaensis was insectivorous-omnivorous, although fruits and vertebrate prey were also consumed, indicating also and opportunistic diet. Caluromys lanatus is classifi ed as a more frugivorous species, besides the consumption of vertebrate prey. Insectivorous habit seems to be frequent in neotropical small mammals, with consumption of vertebrates or fruits being only opportunistic. The insectivory (except for C. lanatus) and opportunistic habit appear to dominate among the small mammal species studied. Key words: Micoureus paraguayanus, Caluromys lanatus, Monodelphis sorex, Akodon paranaensis, food habits.A composição da dieta de quatro espécies de pequenos mamíferos foi estudada no oeste do Paraná, sul do Brasil. Os animais foram amostrados durante o resgate de fauna ocorrido em outubro de 1998, durante a implementação da usina hidrelétrica de Salto Caxias. Os animais foram sacrificados logo após suas capturas. As análises foram baseadas nos tratos digestórios das espécies. As espécies Caluromys lanatus, Micoureus paraguayanus, Monodelphis sorex (Marsupialia) e Akodon paranaensis (Rodentia) se mostraram heterogêneas quanto à composição da dieta, tanto para itens animais quanto vegetais. Os cecos das quatro espécies tinham em geral uma menor proporção de insetos quando comparados às demais partes do trato digestório. No entanto, quando avaliado o volume consumido de cada item alimentar, os artrópodes foram mais importantes na dieta de três espécies de pequenos mamíferos do que frutos. Estes foram mais importantes para C. lanatus. A quantidade estimada de vegetais (sementes e estruturas vegetativas) foi muito mais importante para C. lanatus, principalmente no material retirado do ceco. Ressalta-se ainda a grande proporção de sementes inteiras tanto no trato digestório como nos cecos em todas as espécies estudadas, em comparação com a proporção de sementes predadas, evidenciando estas espécies como dispersoras de sementes. Monodelphis sorex parece ter uma dieta mais insetívora, por ser um pequeno mamífero cursorial, contudo há a evidência de frugivoria ou carnivoria para a espécie. Akodon paranaensis mostrou-se como insetívoro-onívoro, contudo frutos e presas vertebradas também foram consumidos, indicando também uma dieta oportunista. Caluromys lanatus foi classificado como a espécie mais frugívora, embora tenha consumido vertebrados. O hábito em geral insetívoro observado é freqüente em pequenos mamíferos neotropicais, com o consumo de vertebrados ou frutos de forma oportunista. A insetivoria, exceto para C. lanatus, e hábito alimentar oportunista parecem dominar entre os pequenos mamíferos estudados. Palavras-chave: Micoureus paraguayanus, Caluromys lanatus, Monodelphis sorex, Akodon paranaensis, hábitos alimentares

THE INFLUENCE OF HIGHWAY BR 262 ON THE LOSS OF CERRADO VEGETATION COVER IN SOUTHWESTERN BRAZIL

The effects of a highway extending beyond the axis of the road, within regions with variable dimensions depending on the variables tested, are called “road effect zones”. The limits can vary according to the landscape and in areas where human occupation is more intense and, especially where settlements are formed along the roads, there is an accelerated rhythmof environmental degradation through destructive exploitation. Currently, only 35% of the Cerrado biome remain unchanged for the Brazilian remnants, and the southwestern part of the biome mostly suffers from deforestation. During the ‘80s, in the State of Mato Grosso do Sul, there was a high rate of colonization and as a result vast areas of native vegetation were replaced by agricultural lands, such as cash crops and pasture. The objective of this study was to estimate the evolution of deforestation in the cerrado within a road zone effect of 200 km on the highway BR-262, between Campo Grande and Miranda (Mato Grosso do Sul State, Brazil). The effects were evaluated by using temporal and spatial analysis with geotechnology techniques and remote sensing data. Our hypotheses were that there is an evolution of deforestation since the 1980s, and that deforestation is more intense near the highway. The study area comprises 9 km (divided in three different distances) for each side of the road. This road begins in Brazil\u27s central highlands and extends into the Pantanal, an environmentally important area. Based on satellite images from 1985 and 2001 we could estimate a 32.6% loss of cerrado along the highway. In addition, we found that the road impacts the distribution of vegetation cover, with pasture growing near the road, and forest cover growing further away. The roads are considered an accelerating factor to habitat degradation.The effects of a highway extend beyond the axis of the road, within regions with variable dimensions depending on the variables tested, called as “road effect zones”. These limits can vary according to the landscape and in areas where human occupation is more intense, especially where settlements are formed along the roads, there is an accelerated rhythm of environmental degradation through destructive exploitation. Currently, only 35% of the Cerrado biome remains unchanged for the Brazilian remnants, and the southwestern part of the biome most suffers from deforestation. During the decade of the \u2780s, in State of Mato Grosso do Sul, there was a high rate of colonization, and as a result, vast areas of native vegetation were replaced by agricultural lands such as cash crops and pasture. The objective of this study is to estimate the evolution of deforestation in the cerrado within a road zone effect of 200 km on highway BR 262, between Campo Grande and Miranda (Mato Grosso do Sul State, Brazil). The effects were evaluated by using temporal and spatial analysis with geotechnologies techniques and remote sensing data. Our hypotheses were that there is a continuous evolution of deforestation since the 1980s, and that deforestation is more intense near the highway. The study area comprises 9 km (divided in three different distances) for each side of the road. This road begins in Brazil\u27s central highlands and extends into the Pantanal, an environmentally important area. Based on satellite images from 1985 and 2001 we could estimate a 32.6% loss of Cerrado along the highway, representing a 2.04% annual loss of Cerrado. In addition, we found that the road impacts the distribution of vegetation cover, with pasture growing near the road, and forest cover growing further away. The roads are considered an accelerating factor to habitat degradation

Comparison between sampling methods and baits efficiency in attracting mammals in Brazilian savanna

O Brasil abriga a maior diversidade de mamíferos do mundo e, no Cerrado, há registro de 251 espécies, das quais 32 são endêmicas. O estabelecimento de áreas protegidas tem sido uma das estratégias de conservação adotadas para esse Bioma. Ainda que existam vários trabalhos sobre mastofauna desenvolvidos em áreas de conservação, os métodos de amostragem utilizados nesses trabalhos diferem em vários aspectos. Este trabalho teve por objetivo comparar metodologias de amostragem da mastofauna de médio e grande porte, testar a eficiência de diferentes iscas na atração desses mamíferos em parcelas de areia e testar a relação das espécies mais amostradas com as iscas utilizadas em uma Unidade de Conservação periurbana no Cerrado brasileiro, em Campo Grande, MS. O registro de mamíferos de médio e grande porte foi feito através de busca ativa, parcelas de areia e armadilhas fotográficas. Foram registradas 18 espécies de mamíferos de médio e grande porte, sendo duas delas ameaçadas de extinção. Entre os diferentes métodos utilizados, parcelas de areia foi o mais eficiente. As espécies mais amostradas não se relacionaram com nenhuma isca específica. Considerando o tamanho e a localização do parque, é notável a importância deste na representatividade da mastofauna de maior porte do Cerrado.Palavras-chave: parques, animais silvestres, conservação.Brazil is home to the greatest diversity of mammals in the world, and for the Cerrado 251 species are recorded, of which 32 are endemic. The establishment of protected areas has been one of the conservation strategies adopted for this biome. Although there are several studies developed on mammals in conservation areas, the sampling methods used in these studies differ in several aspects. This study aimed to compare sampling methodologies of medium and large-sized mammals, test the efficiency of different baits in attracting these mammals in sand plots and test the relationship of the most sampled species with baits used in a peri-urban Conservation Unit in Brazilian Savanna, in Campo Grande, Mato Grosso do Sul State. The registry of medium and large-sized mammals was done through active search, sand plots and camera traps. Eighteen species of medium and large-sized mammals were recorded, two of which are endangered. Among the different methods used, sand-plots were the most efficient. The most sampled species were not related to any specific bait. Considering the size and location of the park, the importance of its representation in the fauna of large mammals in the Cerrado is remarkable.Key words: parks, wildlife, conservation

Variação espacial de atropelamentos de mamíferos em área de restinga no estado do Espírito Santo, Brasil

Millions of wild animals die run over every year in Brazil. Various taxonomic groups are affected, including amphibians, reptiles, birds and mammals. However, few studies have quantified and identified which animals are the most vulnerable. This work aims to describe the abundance, the species composition and the richness of mammal road kills over a road stretch, in southeast Brazil. It was also assessed if there is any difference in the number of road kills between the rainy and the dry seasons, and the spatial distribution of collisions along the highway. The road kills were recorded over four years and 10 months. A total of 258 individuals belonging to 22 species, 13 families and 7 orders were recorded. The most recorded species were Didelphis aurita, Cerdocyon thous and Procyon cancrivorus. There was no significant difference in the mortality of mammals between the rainy and the dry seasons. Three stretches, with 86, 32 and 31 records, had the highest numbers of road kills. In these places the highway borders or crosses conservation units and forest fragments that are not legally protected. The high number of road kills between km 40 and 50 is probably due to the existence of concrete barriers that separate highway strips.Keywords: roads, mammals, mortality.Milhões de animais silvestres morrem atropelados todos os anos no Brasil e diferentes grupos taxonômicos são afetados, incluindo anfíbios, répteis, aves e mamíferos. Porém, há poucos estudos identificando e quantificando os grupos mais afetados. Os objetivos deste trabalho são descrever a abundância, a composição de espécies e a riqueza de mamíferos atropelados em um trecho de rodovia no estado do Espírito Santo, Brasil. O estudo avaliou, também, se houve diferença no número de atropelamentos entre estações e a distribuição espacial das colisões. Os animais atropelados foram registrados durante quatro anos e 10 meses. Foram registrados 258 indivíduos pertencentes a 22 espécies, 13 famílias e sete ordens. As espécies com maior número de registros foram Didelphis aurita, Cerdocyon thous e Procyon cancrivorus. Não houve diferença significativa na mortalidade de mamíferos entre as estações chuvosa e seca. Três trechos da rodovia, com 86, 32 e 31 casos, apresentaram alto número de atropelamentos. Nesses locais, a rodovia margeia ou atravessa unidades de conservação e fragmentos florestais que não estão legalmente protegidos. O elevado número de atropelamentos entre os km 40 e 50 deve-se, provavelmente, à existência, nesse trecho, de barreiras de concreto separando as faixas de rolamento da rodovia.Palavras-chave: estradas, mastofauna, mortalidade

BRAZIL ROAD-KILL: a dataset of wildlife terrestrial vertebrate road-kills

Mortality from collision with vehicles is the most visible impact of road traffic on wildlife. Mortality due to roads (hereafter road-kill) can affect the dynamic of populations of many species and can, therefore, increase the risk of local decline or extinction. This is especially true in Brazil, where plans for road network upgrading and expansion overlaps biodiversity hotspot areas, which are of high importance for global conservation. Researchers, conservationists and road planners face the challenge to define a national strategy for road mitigation and wildlife conservation. The main goal of this dataset is a compilation of geo-referenced road-kill data from published and unpublished road surveys. This is the first Data Paper in the BRAZIL series (see ATLANTIC, NEOTROPICAL, and BRAZIL collections of Data Papers published in Ecology), which aims make public road-kill data for species in the Brazilian Regions. The dataset encompasses road-kill records from 45 personal communications and 26 studies published in peer-reviewed journals, theses and reports. The road-kill dataset comprises 21,512 records, 83% of which are identified to the species level (n = 450 species). The dataset includes records of 31 amphibian species, 90 reptile species, 229 bird species, and 99 mammal species. One species is classified as Endangered, eight as Vulnerable and twelve as Near Threatened. The species with the highest number of records are: Didelphis albiventris (n = 1,549), Volatinia jacarina (n = 1,238), Cerdocyon thous (n = 1,135), Helicops infrataeniatus (n = 802), and Rhinella icterica (n = 692). Most of the records came from southern Brazil. However, observations of the road-kill incidence for non-Least Concern species are more spread across the country. This dataset can be used to identify which taxa seems to be vulnerable to traffic, analyze temporal and spatial patterns of road-kill at local, regional and national scales and also used to understand the effects of road-kill on population persistence. It may also contribute to studies that aims to understand the influence of landscape and environmental influences on road-kills, improve our knowledge on road-related strategies on biodiversity conservation and be used as complementary information on large-scale and macroecological studies. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper

Dieta e Frugivoria por Marsupiais Didelfideos em uma floresta estacional semidecidual no Parque Nacional Do Iguaçu, Paraná, Brasil

Atualmente a ordem Didelphimorphia apresenta uma única família, denominada Didelphidae, distribuída ao longo do continente americano (Emmons & Feer, 1997). No Brasil, são conhecidos pelo menos 15 gêneros e 65 espécies (Fonseca et al., 1996). Esse número ultrapassa 70 espécies quando considerada toda a Região Neotropical (Emmons & Feer, 1997). Os marsupiais neotropicais ocorrem desde as florestas austrais e habitats arbustivos da Patagônia, passando pelos Andes e toda extensão das florestas de planície subtropicais e tropicais, cerrados e chaco, até as regiões áridas de caatinga. Estendem-se ainda, representados por uma única espécie de gambá (Didelphis virginiana), até as regiões temperadas da América do Norte (Emmons & Feer, 1997). Os marsupiais didelfídeos ocupam uma grande variedade de nichos, sendo a maior parte dos gêneros de marsupiais neotropicais arborícolas ou ao menos escansoriais (Fonseca et al., 1996; Emmons & Feer, 1997). Podem ocupar um gradiente desde as espécies mais frugívoras, onívoras até as mais carnívoras (Santori & Astúa de Moraes, 2005). Essas diferenças entre as espécies nos nichos que ocupam podem permitir a coexistência de um maior número de espécies na comunidade, e devem implicar em especializações da morfologia diretamente ligadas à locomoção e à alimentação (Vieira, 2005). Estes marsupiais são remanescentes de um grupo ancestral da fauna de mamíferos terrestres que viveu durante a maior parte do Cenozóico, alcançando alta diversidade de espécies na América do Sul (Marshall & Cifelli, 1990). Os gambás e as cuícas neotropicais estão entre os mamíferos contemporâneos mais diversificados, sendo considerados um grupo de evolução mais recente (Mioceno) dentre os marsupiais (Oliveira & Goin, 2005). Os marsupiais atuais são mais arborícolas e onívoros, e isso pode ser atribuído à invasão de espécies de mamíferos placentários provenientes dos continentes do norte durante o Plioceno, o que foi chamado de 'Grande Intercâmbio Americano'. Essas espécies invasoras foram melhores competitivamente, conduzindo as espécies mais especializadas à extinção, entre elas alguns grandes marsupiais carnívoros, e colaborando para que as espécies mais arborícolas e/ou mais onívoras sobrevivessem (Webb & Rancy, 1996). Entre os gêneros conhecidos para a região neotropical, nove são compostos por espécies que usam o estrato arbóreo, mesmo que esporadicamente (Didelphis, Philander, Marmosa, Gracilinanus, Micoureus, Marmosops, Caluromys, Caluromysiops e Glironia), quatro usam exclusivamente o solo (Criptonanus, Thylamys, Monodelphis e Metachirus), ao passo que outros dois são associados a ambientes aquáticos (Lutreolina e Chironectes) (Fonseca et al., 1996; Emmons & Feer, 1997). Uma das vantagens que a vida arbórea traz é a possibilidade de se ter acesso a frutos antes que esses caiam e fiquem disponíveis no solo para outros organismos (Miranda & Passos, 2004). Para mamíferos não voadores, parece haver uma relação estreita entre a dieta do animal e o estrato vertical ocupado (Malcom, 1995; Vieira & Astúa de Moraes, 2003). Sendo assim, as espécies com maior atividade arbórea (e.g. Caluromys e Micoureus) seriam também aquelas para as quais os frutos são mais importantes na dieta (Charles Dominique, 1983; Santori & Astúa de Moraes, 2005). Devido à ampla distribuição geográfica dos marsupiais didelfídeos no Brasil, o conhecimento sobre ecologia dos membros desta família vem sendo acrescido também de informações sobre os hábitos alimentares. Os primeiros estudos no Brasil tiveram início na década de 40; contudo desde essa época até o momento, os mais variados estudos sobre dieta tratam de apenas uma pequena parcela dos marsupiais neotropicais, sendo que os biomas são pouco explorados em função de produção e disponibilidade de alimento aos marsupiais. O presente estudo aborda no primeiro capítulo, a dieta de Didelphis aurita, Micoureus paraguayanus e de Caluromys lanatus, e a relação da dieta como uso do estrato vertical e partição de recursos entre essas espécies. Após a caracterização das dietas, as relações entre disponibilidade de alimento no ambiente, amplitude alimentar e ciclo reprodutivo de D. aurita são tratados no segundo capítulo. Nestes dois capítulos, são enfocados também o oportunismo, a frugivoria e a capacidade de dispersão de sementes por estes animais.This study has the aim to analyse the diet of didelphid marsupials, namely the black-eared opossum Didelphis aurita, the woolly mouse opossum Micoureus paraguayanus and the western woolly opossum Caluromys lanatus, besides the effects of resource partitioning among these sympatric species, in a seasonal forest of southern Brazil. For this purpose, 100 live traps were set in the forest canopy (20 m apart; above 10 m in height) and other 50 (40 m apart) on the ground from August 2004 to July 2005. Species of opossums captured were identified and separated by sex, age and by their reproductive condition in order to compare diets among these classes. Their faeces were collected on the trap floor and analyzed after being washed with a 1 mm mesh. After 8,500 trap-nights, 41 faecal samples of D. aurita, eight of M. paraguayanus and two of C. lanatus were sampled. The three species of opossum studied were heterogeneous in relation to thein diet composition, being significantly different from each other. When compared, individuals of D. aurita trapped in the canopy vs. those trapped in the floor level, or even regarding age and sex classes, did not differ in diet composition. Nevertheless, all individuals of D. aurita trapped at the canopy were young, which corroborates an observed trend to young have a larger dietary niche not a young canopy was captured while the ones on the floor were captured as young individuals as adult individuals. All species presented insects in their diets, but with a to consume fruits (both species) or vertebrates (D. aurita). Hence, D. aurita was more omnivorous, and M. paraguayanus, regarding its little faecal samples, revealed several fruit species in their diet, such as Cecropia pachystachia and Piper sp. The role of these marsupials as opportunistic consumers as well as the role of body size and habitat differences determining trends in diet are discussed.Seasonal forests have marked periods of rains and drought, and animals living there are thought to be adapted to this condition. This study aims to obtain information about relationships between availability of food resources (fruits) and biotic parameters of didelphid marsupials, such as reproduction level and fruit consumption, in a seasonal semideciduous forest of southern Brazil. This study was developed with Micoureus paraguayanus and Didelphis aurita, focusing mainly the similarities in the rhythms of consumption rather than their main differences in foraging. For this purpose, 100 live traps were set in the forest canopy (20 m apart; above 10 m in height) and other 50 (40 m apart) on the ground from August 2004 to July 2005. Their faeces were collected on a trap floor and seeds from them were identified and counted. The fruit availability in the area was quantified monthly through the collection of flesh fruits and flowers available on the ground, at 10 transect lines of 1 m in width. Because fruits of Piper do not detach usually from stems, this shrub species was sampled by counting fruiting individuals in the same 10 transect lines. Results were analyzed based on 33 faecal samples of D. aurita and eight of M. paraguayanus. Regarding fruits, diversity indexes of Shannon observed for the environment and for the marsupials species usually matched, being higher during the rainy months (November to March). Hence, rhythms of fructification of Piper sp. correlated to their consumption by marsupials (rs = 1.00, P = 0.04, for D. aurita and rs = 0.40, P = 0.60, for M. paraguayanus). There were trends to the major proportion of independent young and lactant females of D. aurita correlate to the peaks of fruit availability in the environment, mainly in November and January. Thus, the availability of resources had an important role in the reproduction and foraging behavior of the marsupial species. Marsupials are also adapted to reproduce and release young during favourable times, which matched with the warmer and rainy season at the seasonal semideciduous forest of southern Brazil