ABREU, M.S.L.; SCHMITZ, G.W.; OLIVEIRA, L.R. 2015. Recursos alimentares nos estratos verticais e sua relação com pequenos mamíferos em uma Floresta de Araucária do sul do Brasil. Revista de Ciências Ambientais 9(2):131-144. doi: 10.18316/1981-8858.16
Abstract. Food resources on the vertical strata and their relationship with small mammals in an Araucaria forest of southern Brazil. This study presents the relationship between the use of different layers by non-volant small mammals and the food resources availability in an Araucaria Forest area from southern Brazil. In this sense, 150 live traps were placed on the ground, understory and canopy. The availability of resources in the layers was evaluated by counting fruits, seeds and captured invertebrates. As a result, 10 species were recorded of non-volant small mammals. An inverse relationship was found between captures of: Akodon montensis and availability of fruits and seeds on the ground (R = -0.95, P = 0.05); Juliomys sp. and invertebrates abundance in the canopy (R = -0.96, P = 0.04); and Gracilinanus microtarsus and total food availability in the canopy (R = -0.99, P = 0.008). The results suggest that in times of food scarcity, small mammals in the Araucaria Forest may need more time searching for food, increasing catch rates in the strata where they live.
Mostrando postagens com marcador Araucaria forest. Mostrar todas as postagens
Mostrando postagens com marcador Araucaria forest. Mostrar todas as postagens
terça-feira, 22 de dezembro de 2015
sábado, 22 de agosto de 2015
Mastofauna do Planalto das Araucárias, Rio Grande do Sul, Brasil
MARQUES, R.V.; CADEMARTORI, C.V.; PACHECO, S.M. 2011. Mastofauna do Planalto das Araucárias, Rio Grande do Sul, Brasil. Revista Brasileira de Biociências 9(3):278-288.
Abstract. Mammals from Araucaria’s Plateau, state of Rio Grande do Sul, Brazil. Wild small (including flying), medium and large mammals long term surveys were carried out in Protected areas in Araucarias Plateau in state of Rio Grande do Sul, Brazil. Studies were done in native pine forests (Araucaria angustifolia), Araucaria plantation, recuperation stage of native vegetation after deforestation and around urban areas. Study methods included the use of Tomahawk traps, pitffal traps, mist nets, camera traps, footprints, direct observations of animals and dead animals in roads. Sixty six species of native mammals and one exotic species (hare – Lepus europaeus) were detected. Araucaria’s Plateau is important for conservation of mammals because has natural environments that support endangered species.
Abstract. Mammals from Araucaria’s Plateau, state of Rio Grande do Sul, Brazil. Wild small (including flying), medium and large mammals long term surveys were carried out in Protected areas in Araucarias Plateau in state of Rio Grande do Sul, Brazil. Studies were done in native pine forests (Araucaria angustifolia), Araucaria plantation, recuperation stage of native vegetation after deforestation and around urban areas. Study methods included the use of Tomahawk traps, pitffal traps, mist nets, camera traps, footprints, direct observations of animals and dead animals in roads. Sixty six species of native mammals and one exotic species (hare – Lepus europaeus) were detected. Araucaria’s Plateau is important for conservation of mammals because has natural environments that support endangered species.
sábado, 28 de junho de 2014
Patterns of arboreal and terrestrial space use by non-volant small mammals in an Araucaria forest of southern Brazil
ABREU, M.S.L.; OLIVEIRA, L.R. 2014. Patterns of arboreal and terrestrial space use by non-volant small mammals in an Araucaria forest of southern Brazil. Anais da Academia Brasileira de Ciências 86(2):807-819.
Abstract. Despite the advances in the techniques for researching arboreal small mammals, detailed ecological data, such as habitat use patterns, are practically nonexistent for many species. Using 150 live-traps installed on the ground, understory (1.0-5.0m) and canopy (>5.0m) we investigated patterns of arboreal and terrestrial space use by small mammals in an Araucaria Forest in southern Brazil (29º29’08’’S; 50º12’26’’W). We also measured 19 microhabitat variables that could potentially influence the abundance of such mammals on each trap station. The results indicated that Akodon montensis and A. serrensis were mainly terrestrial. Delomys dorsalis was also terrestrial, but it also used understory (17.24% of captures). Juliomys sp. and Gracilinanus microtarsus were the most arboreal small mammals recorded. A. montensis was associated with dense vegetation, while A. serrensis selected positively opened areas. Juliomys sp. and G. microtarsus were associated to microhabitat variables related to the access and movement within the canopy. Moreover, bromeliads on arboreal layer were an important factor for these two arboreal species. This is the first study to report microhabitat associations by Juliomys sp. and A. serrensis, and we demonstrated that vertical stratification and microhabitat use were both synergic mechanisms to determine habitat use by small mammals on the Araucaria Forest of southern Brazil.
Abstract. Despite the advances in the techniques for researching arboreal small mammals, detailed ecological data, such as habitat use patterns, are practically nonexistent for many species. Using 150 live-traps installed on the ground, understory (1.0-5.0m) and canopy (>5.0m) we investigated patterns of arboreal and terrestrial space use by small mammals in an Araucaria Forest in southern Brazil (29º29’08’’S; 50º12’26’’W). We also measured 19 microhabitat variables that could potentially influence the abundance of such mammals on each trap station. The results indicated that Akodon montensis and A. serrensis were mainly terrestrial. Delomys dorsalis was also terrestrial, but it also used understory (17.24% of captures). Juliomys sp. and Gracilinanus microtarsus were the most arboreal small mammals recorded. A. montensis was associated with dense vegetation, while A. serrensis selected positively opened areas. Juliomys sp. and G. microtarsus were associated to microhabitat variables related to the access and movement within the canopy. Moreover, bromeliads on arboreal layer were an important factor for these two arboreal species. This is the first study to report microhabitat associations by Juliomys sp. and A. serrensis, and we demonstrated that vertical stratification and microhabitat use were both synergic mechanisms to determine habitat use by small mammals on the Araucaria Forest of southern Brazil.
quarta-feira, 6 de julho de 2011
Fotos: Nasua nasua
Espécie: Nasua nasia (quati).
Fotógrafo: Maury S.L. Abreu.
Contato: maury.abreu@gmail.com
quarta-feira, 29 de junho de 2011
Fotos: Cryptonanus guahybae
Espécie: Cryptonanus guahybae (cuíca).
Fotógrafo: Maury S.L. Abreu.
Contato: maury.abreu@gmail.com
sábado, 18 de junho de 2011
Niche overlap and resource partitioning between two sympatric fox species in southern Brazil
VIEIRA, E.M.; PORT, D. 2007. Niche overlap and resource partitioning between two sympatric fox species in southern Brazil. Journal of Zoology, London 272:57-63.
Abstract. Mechanisms that favour the co-occurrence of morphologically and ecologically similar species in South America are potentially relevant, because two or more species often occur in sympatry. In the present study, we investigated possible mechanisms of resource partitioning between two sympatric species of foxes, the crab-eating fox Cerdocyon thous and the pampas fox Pseudalopex gymnocercus, in the National Park of Aparados da Serra in southern Brazil (29º10'S, 50º05'W). We considered three main niche dimensions – habitat, diet and time – and evaluated the overlap between the two species in these dimensions. We conducted the study from June 2000 to October 2001 in an area composed of open grasslands and Araucaria forests. We studied the foxes by using a combination of scat analysis and direct observation. A comparison of their diet indicated that it was very similar for both species in all seasons (Pianka’s indexes ranging from 0.920 to 0.957). The most common food item for both species of foxes was rodents, followed by coleopterans, birds and plant remains (seeds and fruits). As expected by the nichecomplementarity hypothesis, we detected differences along other niche axes. Pseudalopex gymnocercus seemed to occur only in open areas, including grasslands and dirt roads, whereas C. thous was more generalist in habitat use, occurring both inside and at the edge of forests. However, both fox species were common in grassland habitats, where they might compete for resources. The differences were more marked for activity time, with the crab-eating fox being significantly more nocturnal (circular mean of time of sighting=23:39 h, SE=56 min) than the pampas fox (circular mean=19:56 h, SE=64 min; Watson’s F=6.06, P=0.02). We suggest that the larger C. thous could be limiting the activity of P. gymnocercus by interference competition.
Abstract. Mechanisms that favour the co-occurrence of morphologically and ecologically similar species in South America are potentially relevant, because two or more species often occur in sympatry. In the present study, we investigated possible mechanisms of resource partitioning between two sympatric species of foxes, the crab-eating fox Cerdocyon thous and the pampas fox Pseudalopex gymnocercus, in the National Park of Aparados da Serra in southern Brazil (29º10'S, 50º05'W). We considered three main niche dimensions – habitat, diet and time – and evaluated the overlap between the two species in these dimensions. We conducted the study from June 2000 to October 2001 in an area composed of open grasslands and Araucaria forests. We studied the foxes by using a combination of scat analysis and direct observation. A comparison of their diet indicated that it was very similar for both species in all seasons (Pianka’s indexes ranging from 0.920 to 0.957). The most common food item for both species of foxes was rodents, followed by coleopterans, birds and plant remains (seeds and fruits). As expected by the nichecomplementarity hypothesis, we detected differences along other niche axes. Pseudalopex gymnocercus seemed to occur only in open areas, including grasslands and dirt roads, whereas C. thous was more generalist in habitat use, occurring both inside and at the edge of forests. However, both fox species were common in grassland habitats, where they might compete for resources. The differences were more marked for activity time, with the crab-eating fox being significantly more nocturnal (circular mean of time of sighting=23:39 h, SE=56 min) than the pampas fox (circular mean=19:56 h, SE=64 min; Watson’s F=6.06, P=0.02). We suggest that the larger C. thous could be limiting the activity of P. gymnocercus by interference competition.
sábado, 14 de maio de 2011
Mamiferos carnívoros e sua relação com a diversidade de hábitats no Parque Nacional dos Aparados da Serra, sul do Brasil
SANTOS, M.F.M.; PELLANDA, M.; TOMAZZONI, A.C.; HASENACK, H.; HARTZ, S.M. 2004. Mamiferos carnívoros e sua relação com a diversidade de hábitats no Parque Nacional dos Aparados da Serra, sul do Brasil. Iheringia, Série Zoologia 94(3):235-245.
Abstract. Carnivore mammals and their relation with habitat diversity in Aparados da Serra National Park, southern Brazil. A survey of carnivore mammals was accomplished in Aparados da Serra National Park from February 1998 to March 2000. The park has 10.250 ha and is considered a biodiversity core area of the Atlantic Forest Biosphere Reserve in the Rio Grande do Sul State, Brazil. The landscape is characterized by relatively well preserved relicts of Araucaria angustifolia (Bertol.) Kuntze forest, grassland and Atlantic Forest, which have contributed for the survival of endangered carnivore mammals. The National Park was divided in a grid of 16 km² cells using a 1:50.000 scale map. The animals were recorded using indirect methods, by identifying signs (scats, tracks) and direct observation in 2.5 km long and 5 m wide transects, with 10 replicates in each grid cell. Interviews with local people were also used to confirm the animal presence. A total of 13 species was recorded: Procyon cancrivorus (Cuvier, 1798), Pseudalopex gymnocercus (G. Fischer, 1814), Leopardus pardalis (Linnaeus, 1758) and Cerdocyon thous (Linnaeus, 1766) were the most frequent species registered. Nasua nasua (Linnaeus, 1766), Herpailurus yaguarondi (Lacépède, 1809), Chrysocyon brachyurus (Illiger, 1815), Eira barbara (Linnaeus, 1758), Leopardus sp., Puma concolor (Linnaeus, 1771), Galictis cuja (Molina, 1782), Conepatus chinga (Molina, 1892) and Lontra longicaudis (Olfers, 1818) showed lower frequencies. The Park presented areas with significant differences (Mantel Test, P< 0.05) in species richness and composition related to habitat classes. Areas with high habitat richness presented high species richness. The Araucaria forest was the habitat that presented the higher carnivore richness. The border areas of the Park are influenced by several environmental degradation factors that could be affecting the distribution of carnivores.
Abstract. Carnivore mammals and their relation with habitat diversity in Aparados da Serra National Park, southern Brazil. A survey of carnivore mammals was accomplished in Aparados da Serra National Park from February 1998 to March 2000. The park has 10.250 ha and is considered a biodiversity core area of the Atlantic Forest Biosphere Reserve in the Rio Grande do Sul State, Brazil. The landscape is characterized by relatively well preserved relicts of Araucaria angustifolia (Bertol.) Kuntze forest, grassland and Atlantic Forest, which have contributed for the survival of endangered carnivore mammals. The National Park was divided in a grid of 16 km² cells using a 1:50.000 scale map. The animals were recorded using indirect methods, by identifying signs (scats, tracks) and direct observation in 2.5 km long and 5 m wide transects, with 10 replicates in each grid cell. Interviews with local people were also used to confirm the animal presence. A total of 13 species was recorded: Procyon cancrivorus (Cuvier, 1798), Pseudalopex gymnocercus (G. Fischer, 1814), Leopardus pardalis (Linnaeus, 1758) and Cerdocyon thous (Linnaeus, 1766) were the most frequent species registered. Nasua nasua (Linnaeus, 1766), Herpailurus yaguarondi (Lacépède, 1809), Chrysocyon brachyurus (Illiger, 1815), Eira barbara (Linnaeus, 1758), Leopardus sp., Puma concolor (Linnaeus, 1771), Galictis cuja (Molina, 1782), Conepatus chinga (Molina, 1892) and Lontra longicaudis (Olfers, 1818) showed lower frequencies. The Park presented areas with significant differences (Mantel Test, P< 0.05) in species richness and composition related to habitat classes. Areas with high habitat richness presented high species richness. The Araucaria forest was the habitat that presented the higher carnivore richness. The border areas of the Park are influenced by several environmental degradation factors that could be affecting the distribution of carnivores.
sábado, 16 de abril de 2011
Consumo de pequenos mamíferos por canídeos simpátricos do sul do Brasil: sobreposição de nichos e seleção de presas
ABREU, M.S.L.; WIELICZKO, A.R.; MESQUITA, A.; VIEIRA, E.M. 2010. Consumo de pequenos mamíferos por canídeos simpátricos do sul do Brasil: sobreposição de nichos e seleção de presas. Neotropical Biology and Conservation 5(1):16-23.
Resumo. O graxaim-do-mato (Cerdocyon thous) e o graxaim-do-campo (Lycalopex gymnocercus) são dois canídeos endêmicos da região Neotropical que ocorrem em simpatria no estado do Rio Grande do Sul, sul do Brasil. Estudos anteriores indicaram que ambas as espécies se alimentam principalmente de pequenos mamíferos, sem diferenças detectáveis em suas dietas, ao menos quando não há a determinação dos gêneros de mamíferos consumidos. No presente estudo, o objetivo foi avaliar a real similaridade na composição da dieta desses animais, procurando identifi car os gêneros de pequenos mamíferos consumidos. Além disso, investigaram-se possíveis padrões de seleção de presas pelos canídeos. Para isso, foram analisadas 222 amostras fecais coletadas no Parque Nacional dos Aparados da Serra (RS) entre os anos de 2000 e 2005, identificando a espécie de canídeo por meio de análise de pelos. Também foi realizado, entre 2000 e 2002, um levantamento de pequenos mamíferos ocorrentes na área, mediante a utilização de técnicas de captura, marcação e recaptura. Os resultados indicaram que as duas espécies de canídeos não diferem signifi cativamente em relação aos gêneros de pequenos mamíferos consumidos. Além disso, verifi cou-se que as duas espécies parecem preferir se alimentar de roedores do gênero Akodon. Por outro lado, esses canídeos predaram as espécies do gênero Oligoryzomys em grau menor do que o esperado. Os resultados obtidos sugerem que a similaridade de dieta entre os canídeos estudados é muito alta, mesmo sob uma análise mais refinada dos itens consumidos por esses animais. Tais resultados fundamentam a hipótese de que a separação de nicho entre C. thous e L. gymnocercus deve ocorrer por meio de fatores diferentes da dieta, como hábitat ou horário de atividade.
Resumo. O graxaim-do-mato (Cerdocyon thous) e o graxaim-do-campo (Lycalopex gymnocercus) são dois canídeos endêmicos da região Neotropical que ocorrem em simpatria no estado do Rio Grande do Sul, sul do Brasil. Estudos anteriores indicaram que ambas as espécies se alimentam principalmente de pequenos mamíferos, sem diferenças detectáveis em suas dietas, ao menos quando não há a determinação dos gêneros de mamíferos consumidos. No presente estudo, o objetivo foi avaliar a real similaridade na composição da dieta desses animais, procurando identifi car os gêneros de pequenos mamíferos consumidos. Além disso, investigaram-se possíveis padrões de seleção de presas pelos canídeos. Para isso, foram analisadas 222 amostras fecais coletadas no Parque Nacional dos Aparados da Serra (RS) entre os anos de 2000 e 2005, identificando a espécie de canídeo por meio de análise de pelos. Também foi realizado, entre 2000 e 2002, um levantamento de pequenos mamíferos ocorrentes na área, mediante a utilização de técnicas de captura, marcação e recaptura. Os resultados indicaram que as duas espécies de canídeos não diferem signifi cativamente em relação aos gêneros de pequenos mamíferos consumidos. Além disso, verifi cou-se que as duas espécies parecem preferir se alimentar de roedores do gênero Akodon. Por outro lado, esses canídeos predaram as espécies do gênero Oligoryzomys em grau menor do que o esperado. Os resultados obtidos sugerem que a similaridade de dieta entre os canídeos estudados é muito alta, mesmo sob uma análise mais refinada dos itens consumidos por esses animais. Tais resultados fundamentam a hipótese de que a separação de nicho entre C. thous e L. gymnocercus deve ocorrer por meio de fatores diferentes da dieta, como hábitat ou horário de atividade.
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