SCOGNAMILLO, D.; MAXIT, I.E.; SUNQUIST, M.; POLISAR, J. 2003. Coexistence of jaguar (Panthera onca) and puma (Puma concolor) in a mosaic landscape in the Venezuelan llanos. Journal of Zoology, London 259:269-279.
Abstract. Jaguar Panthera onca and puma Puma concolor are sympatric throughout the jaguar’s distribution. Although several studies have focused on the interactions between these two predators, the ecological and behavioural factors that promote their coexistence remain unclear. The goal of this study was to identify those factors that facilitate the coexistence of these cats in a mosaic landscape in the Venezuelan llanos. The study was conducted from January 1996 until November 1998. Five jaguars and six pumas were captured and radio-collared. A high degree of spatial overlap was observed between jaguars and pumas, which may be related to the abundance and distribution of prey species. At a fine scale, there was little overlap of puma locations with jaguar locations. Both species were more active at night than during daytime, but seasonal differences were detected in the activity levels of these predators. Major segregation was found in food habits. Jaguars selected for large prey and pumas for medium-sized prey. Jaguars selected for capybara Hydrochaeris hydrochaeris and collared peccary Tayassu tajacu and consumed caiman Caiman crocodilus and white-tailed deer Odocoileus virginianus less than expected. Pumas selected just for collared peccary and also killed caiman less than expected. It is suggested that the abundance of medium-sized prey is an ecological factor that is facilitating the coexistence of jaguar and puma in the study area. Habitat heterogeneity may be another influential factor leading to the coexistence. Seasonal differences in activity levels probably reflect differences in the size and species of prey taken by these cats.
Mostrando postagens com marcador Neotropical region. Mostrar todas as postagens
Mostrando postagens com marcador Neotropical region. Mostrar todas as postagens
sábado, 20 de dezembro de 2014
sábado, 22 de novembro de 2014
Three new bat species in the state of Oaxaca
SANTOS-MORENO, A.; SIPRIANO, L.G. 2014. Three new bat species in the state of Oaxaca, Mexico. Chiroptera Neotropical 20(1):1226-1229.
Abstract. The state of Oaxaca, in southeastern Mexico, is one of the regions with the highest species richness in the country, comparable even with that of some Central American countries. Over the course of a study on the region known as Los Chimalapas, in the southeastern portion of the state of Oaxaca, we recorded the presence of three new species for the state: two New World leaf-nosed bats (Phylloderma stenops and Micronycteris schmidtorum) and one vesper bat (Myotis albescens). The localities of these registersrepresent the northeastern extreme of the geographic distribution of the last two species. The three species included in the present work bring the number of terrestrial mammalian wildlife species in Oaxaca to 209, and the number of bat species to 93.
Abstract. The state of Oaxaca, in southeastern Mexico, is one of the regions with the highest species richness in the country, comparable even with that of some Central American countries. Over the course of a study on the region known as Los Chimalapas, in the southeastern portion of the state of Oaxaca, we recorded the presence of three new species for the state: two New World leaf-nosed bats (Phylloderma stenops and Micronycteris schmidtorum) and one vesper bat (Myotis albescens). The localities of these registersrepresent the northeastern extreme of the geographic distribution of the last two species. The three species included in the present work bring the number of terrestrial mammalian wildlife species in Oaxaca to 209, and the number of bat species to 93.
sábado, 6 de setembro de 2014
Small mammals in the diet of Barn owls, Tyto alba (Aves: Strigiformes) along the mid-Araguaia River in central Brazil
ROCHA, R.G.; FERREIRA, E.; LEITE, Y.L.R.; FONSECA, C.; COSTA, L.P. 2011. Small mammals in the diet of Barn owls, Tyto alba (Aves: Strigiformes) along the mid-Araguaia River in central Brazil. Zoologia 282(6):709-716. doi: 10.1590/S1984-46702011000600003
Abstract. We collected and analyzed 286 Barn owl, Tyto alba (Scopoli, 1769), pellets from two nests in different environments along the mid-Araguaia River in central Brazil. Our analyses revealed that these owls feed mainly on small mammals, especially rodents. Owls from the riverbanks at Fazenda Santa Fé had a more diverse diet, preying mainly on rodents that typically inhabit riparian grasslands – Holochilus sciureus Wagner, 1842 – and forests – Hylaeamys megacephalus (Fischer, 1814) and Oecomys spp., which probably also occur in forest borders or clearings. On the other hand, owls from an agroecosystem at Fazenda Lago Verde preyed mostly on rodent species common in these agrarian fields, Calomys tocantinsi Bonvicino, Lima & Almeida, 2003. Additionally, we compared small mammal richness estimates based on the analysis of owl pellets with estimates from live-trapping in the same areas. Owl pellets revealed two rodent species undetected by live traps – Euryoryzomys sp. and Rattus rattus (Linnaeus, 1758) – and four rodent species were trapped, but not found in owl pellets – Oecomys roberti Thomas, 1904, Pseudoryzomys simplex (Winge, 1887), Rhipidomys ipukensis Rocha, B.M.A. Costa & L.P. Costa, 2011, and Makalata didelphoides (Desmarest, 1817). Traps yielded higher species richness, but these two methods complement each other for surveying small rodents
Abstract. We collected and analyzed 286 Barn owl, Tyto alba (Scopoli, 1769), pellets from two nests in different environments along the mid-Araguaia River in central Brazil. Our analyses revealed that these owls feed mainly on small mammals, especially rodents. Owls from the riverbanks at Fazenda Santa Fé had a more diverse diet, preying mainly on rodents that typically inhabit riparian grasslands – Holochilus sciureus Wagner, 1842 – and forests – Hylaeamys megacephalus (Fischer, 1814) and Oecomys spp., which probably also occur in forest borders or clearings. On the other hand, owls from an agroecosystem at Fazenda Lago Verde preyed mostly on rodent species common in these agrarian fields, Calomys tocantinsi Bonvicino, Lima & Almeida, 2003. Additionally, we compared small mammal richness estimates based on the analysis of owl pellets with estimates from live-trapping in the same areas. Owl pellets revealed two rodent species undetected by live traps – Euryoryzomys sp. and Rattus rattus (Linnaeus, 1758) – and four rodent species were trapped, but not found in owl pellets – Oecomys roberti Thomas, 1904, Pseudoryzomys simplex (Winge, 1887), Rhipidomys ipukensis Rocha, B.M.A. Costa & L.P. Costa, 2011, and Makalata didelphoides (Desmarest, 1817). Traps yielded higher species richness, but these two methods complement each other for surveying small rodents
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.
sábado, 21 de junho de 2014
Revision of the systematic status of Patagonian and Pampean gray foxes (Canidae: Lycalopex griseus and L. gymnocercus) using 3D geometric morphometrics
PREVOSTI, F.J.; SEGURA, V.; CASSINI, G.; MARTIN, G.M. 2013. Revision of the systematic status of Patagonian and Pampean gray foxes (Canidae: Lycalopex griseus and L. gymnocercus) using 3D geometric morphometrics. Mastozoología Neotropical 20(2):289-300.
Abstract. Argentinean “zorros de campo” are currently included in two species: Lycalopex griseus and L. gymnocercus. Lycalopex gymnocercus lives in northern Patagonia and in most of central and northern Argentina. Lycalopex griseus is smaller and lives in Patagonia and throughout western Argentina. A previous traditional morphometric study using cranio-dental measurements considered both forms to be the same species, showing clinal reduction in size from northeastern to southwestern Argentina. Here we tested the synonymy of these foxes and the existence of clinal variation using a large sample and geometric morphometric methods. Our results rejected the separation of these foxes in two different species and confirmed, based on cranium and mandible size and shape that they belong to the same species. Also, we show there is a clinal variation in size that has an allometric component in cranial and mandibular shape, which accounts for the differences between these foxes.
Abstract. Argentinean “zorros de campo” are currently included in two species: Lycalopex griseus and L. gymnocercus. Lycalopex gymnocercus lives in northern Patagonia and in most of central and northern Argentina. Lycalopex griseus is smaller and lives in Patagonia and throughout western Argentina. A previous traditional morphometric study using cranio-dental measurements considered both forms to be the same species, showing clinal reduction in size from northeastern to southwestern Argentina. Here we tested the synonymy of these foxes and the existence of clinal variation using a large sample and geometric morphometric methods. Our results rejected the separation of these foxes in two different species and confirmed, based on cranium and mandible size and shape that they belong to the same species. Also, we show there is a clinal variation in size that has an allometric component in cranial and mandibular shape, which accounts for the differences between these foxes.
sábado, 7 de junho de 2014
Use of carbon and nitrogen stable isotopes to study the feering ecology of small coastal cetacean populations in southern Brazil
HARDT, F.A.S.; CREMER, M.J.; JUNIOR, A.J.T.; BELLANTE, A.; BUFFA, G.; BUSCAINO, G.; MAZZOLA, S.; BARRETO, A.S.; MARTINELLI, L.A.; ZUPPI, G.M. 2013. Use of carbon and nitrogen stable isotopes to study the feering ecology of small coastal cetacean populations in southern Brazil. Biota Neotropica 13(4):90-98.
Abstract: Samples from individuals of the populations of Sotalia guianensis (Guiana) and Pontoporia blainvillei (Franciscana) dolphins living in the Babitonga Bay estuary (26° 28’ S/48° 50’ W), and samples from individuals of a second population of P. blainvillei from a nearshore area (26° 38’ S/48° 41’ W), were collected and analyzed along with their prey between 2000 and 2006, to determine the carbon and nitrogen stable isotope ratios and to verify differences in their feeding ecology. No differences were found in the median ð15N values of Guiana (15.2‰) and Franciscana (15.9‰) dolphins living in Babitonga Bay, nor of nearshore Franciscana (15.0‰) individuals, suggesting no variation in the trophic level of these populations. However, the lack of more information on the isotopic compositions of their putative prey in the nearshore areas prevents the ability to draw definitive conclusions on this issue. The estuarine Franciscana and Guiana dolphin populations presented mean ð13C values of approximately –15.7‰, which were not statistically different from nearshore Franciscana individuals (–14.8‰). Based on stomach content analyses of these species from a previous study, it was reported that there was little overlap in the diet of estuarine Franciscanas and Guiana dolphins. However, based on the similarity of the ð13C values between these two species and of their putative prey, it appears that in fact there is an overlap in the diet of these two species. Based solely on stable isotope analysis, it was not possible to differentiate between estuarine and nearshore Franciscana populations, making it difficult to conclude whether captured nearshore specimens were indeed yearlong residents of these areas. Finally, this study suggests that Franciscana and Guiana dolphin populations are sharing the same resources, mostly L. brevis, D. rhombeus, and S. rastrifer. Therefore, the combination of resource sharing and commercial exploitation of their prey makes these two cetacean species vulnerable.
Abstract: Samples from individuals of the populations of Sotalia guianensis (Guiana) and Pontoporia blainvillei (Franciscana) dolphins living in the Babitonga Bay estuary (26° 28’ S/48° 50’ W), and samples from individuals of a second population of P. blainvillei from a nearshore area (26° 38’ S/48° 41’ W), were collected and analyzed along with their prey between 2000 and 2006, to determine the carbon and nitrogen stable isotope ratios and to verify differences in their feeding ecology. No differences were found in the median ð15N values of Guiana (15.2‰) and Franciscana (15.9‰) dolphins living in Babitonga Bay, nor of nearshore Franciscana (15.0‰) individuals, suggesting no variation in the trophic level of these populations. However, the lack of more information on the isotopic compositions of their putative prey in the nearshore areas prevents the ability to draw definitive conclusions on this issue. The estuarine Franciscana and Guiana dolphin populations presented mean ð13C values of approximately –15.7‰, which were not statistically different from nearshore Franciscana individuals (–14.8‰). Based on stomach content analyses of these species from a previous study, it was reported that there was little overlap in the diet of estuarine Franciscanas and Guiana dolphins. However, based on the similarity of the ð13C values between these two species and of their putative prey, it appears that in fact there is an overlap in the diet of these two species. Based solely on stable isotope analysis, it was not possible to differentiate between estuarine and nearshore Franciscana populations, making it difficult to conclude whether captured nearshore specimens were indeed yearlong residents of these areas. Finally, this study suggests that Franciscana and Guiana dolphin populations are sharing the same resources, mostly L. brevis, D. rhombeus, and S. rastrifer. Therefore, the combination of resource sharing and commercial exploitation of their prey makes these two cetacean species vulnerable.
sábado, 24 de maio de 2014
External features of the dusk dolphin Lagenorhynchus obscurus (Gray, 1828) from Peruvian waters
WAEREBEEK, K.V. 1993. External features of the dusk dolphin Lagenorhynchus obscurus (Gray, 1828) from Peruvian waters. Estudos Oceanológicos 12:37-53.
Abstract. Individual, sexual and developmental variation is quantified in the external morphology and colouration of the dusky dolphin Lagenorhynchus obscurus from Peruvian coastal waters. No significant difference in body length between sexes is found (p = 0.09) and, generally, little sexual dimorphism is present. However, males have a more anteriorly positioned genital slit and anus and their dorsal fin is more curved, has a broader base and a greater surface area than females Although the dorsal fin apparently serves as a secondary sexual character, the use of it for sexing free-ranging dusky dolphins is discouraged because of high overlap in values. Relative growth in 25 body measurements is characterized for both sexes by multiplicative regression equations. The colouration pattern of the dorsal fin, flank patch, thoracic field, flipper stripe and possibly (X², p = 0.08) the eye patch, are independent of maturity status. Flipper blaze and lower lip patch are less pigmented in juveniles than in adults No sexual dimorphism is found in the colour pattern The existence of a discrete "Fitzroy" colour form can not be confirmed from available data. Various cases of anomalous, piebald pigmentation are described, probably equivalent to so-called partial albinism. Adult dusky dolphins from both SW Africa and New Zealand are 8-10 cm shorter than Peruvian specimens, supporting conclusions of separate populations from a recent skull variability study.
Abstract. Individual, sexual and developmental variation is quantified in the external morphology and colouration of the dusky dolphin Lagenorhynchus obscurus from Peruvian coastal waters. No significant difference in body length between sexes is found (p = 0.09) and, generally, little sexual dimorphism is present. However, males have a more anteriorly positioned genital slit and anus and their dorsal fin is more curved, has a broader base and a greater surface area than females Although the dorsal fin apparently serves as a secondary sexual character, the use of it for sexing free-ranging dusky dolphins is discouraged because of high overlap in values. Relative growth in 25 body measurements is characterized for both sexes by multiplicative regression equations. The colouration pattern of the dorsal fin, flank patch, thoracic field, flipper stripe and possibly (X², p = 0.08) the eye patch, are independent of maturity status. Flipper blaze and lower lip patch are less pigmented in juveniles than in adults No sexual dimorphism is found in the colour pattern The existence of a discrete "Fitzroy" colour form can not be confirmed from available data. Various cases of anomalous, piebald pigmentation are described, probably equivalent to so-called partial albinism. Adult dusky dolphins from both SW Africa and New Zealand are 8-10 cm shorter than Peruvian specimens, supporting conclusions of separate populations from a recent skull variability study.
sábado, 10 de maio de 2014
Late Pleistocene (Rancholabrean) Glyptodont and Pampathere (Xenarthra, Cingulata) from Sonora, Mexico
MEAD, J.I.; SWIFT, S.L.; WHITE, R.S. MCDONALD, H.G.; BAEZ, A. 2007. Late Pleistocene (Rancholabrean) Glyptodont and Pampathere (Xenarthra, Cingulata) from Sonora, Mexico. Revista Mexicana de Ciências Geológicas 24(3):439-449.
Abstract. The fossil-rich deposits of Térapa (east-central Sonora) contain more than 60 zoological taxa, many with tropical affinities such as Crocodylus (crocodylian), Hydrochaeris (capybara), and many birds. The deposits also contain the dermal ossicles (osteoderms) of two extinct xenarthrans, a glyptodont (Glyptotherium cylindricum) and a pampathere (giant armadillo; Pampatherium cf. mexicanum). Glyptodont remains are also known from other less-well studied localities in Sonora. The faunas from these localities also contain the genus Bison, which indicates that the deposits are of the Rancholabrean Land Mammal Age, late Pleistocene. The presence of Pampatherium at Térapa and the presence of Glyptotherium at Térapa and the Río Mayo/Río Yaqui sites represent the first published accounts of these species from Sonora, and greatly extends their known geographical distribution during the Rancholabrean by about 1,100 km into northwestern Mexico.
Abstract. The fossil-rich deposits of Térapa (east-central Sonora) contain more than 60 zoological taxa, many with tropical affinities such as Crocodylus (crocodylian), Hydrochaeris (capybara), and many birds. The deposits also contain the dermal ossicles (osteoderms) of two extinct xenarthrans, a glyptodont (Glyptotherium cylindricum) and a pampathere (giant armadillo; Pampatherium cf. mexicanum). Glyptodont remains are also known from other less-well studied localities in Sonora. The faunas from these localities also contain the genus Bison, which indicates that the deposits are of the Rancholabrean Land Mammal Age, late Pleistocene. The presence of Pampatherium at Térapa and the presence of Glyptotherium at Térapa and the Río Mayo/Río Yaqui sites represent the first published accounts of these species from Sonora, and greatly extends their known geographical distribution during the Rancholabrean by about 1,100 km into northwestern Mexico.
sábado, 5 de abril de 2014
The burrows of Dasypus hybridus Cingulata: Dasypodidae)
GONZÁLEZ, E.M.; SOUTULLO, A.; ALTUNA, C.A. 2001. The burrows of Dasypus hybridus Cingulata: Dasypodidae). Acta Theriologica 46(1):53-59.
Abstract. Dasypus hybridus (Desmarest, 1804) inhabits open fields in southern South America. Burrows of D. hybridus were cylindrical with a conical end. They had an entrance and a single tunnel without branches. Three locations of the burrows in the terrain were detected: in banks of dried waterways, near rocks, and in open field. The orientation of 29 burrow mouths was not random and, although they did not point to any cardinal point, in particular there was a strong tendency to avoid the south quadrant. In a sample area of 90 x 140 m, burrow mouths were arranged in a random spatial pattern with a density of 25.4 burrows por ha. Great variation in burrow length was found (118.8 +/- 105.69 cm, CV = 89.0%). Tunnels may be used as refuges and/or for thermo-regulation. The orientation of burrow mouths can also be related to thermoregulation as tunnels are covered from dominant winds, and, for many hours every day, the temperature at the mouths can be influenced by insolation. The possible existence of shelter-burrows and resting-burrows is discussed.
Abstract. Dasypus hybridus (Desmarest, 1804) inhabits open fields in southern South America. Burrows of D. hybridus were cylindrical with a conical end. They had an entrance and a single tunnel without branches. Three locations of the burrows in the terrain were detected: in banks of dried waterways, near rocks, and in open field. The orientation of 29 burrow mouths was not random and, although they did not point to any cardinal point, in particular there was a strong tendency to avoid the south quadrant. In a sample area of 90 x 140 m, burrow mouths were arranged in a random spatial pattern with a density of 25.4 burrows por ha. Great variation in burrow length was found (118.8 +/- 105.69 cm, CV = 89.0%). Tunnels may be used as refuges and/or for thermo-regulation. The orientation of burrow mouths can also be related to thermoregulation as tunnels are covered from dominant winds, and, for many hours every day, the temperature at the mouths can be influenced by insolation. The possible existence of shelter-burrows and resting-burrows is discussed.
Key Words:
behavior,
Cingulata,
density,
fossorial mammals,
medium and large mammals,
neotropical mammals,
Neotropical region,
population ecology,
Uruguay
sábado, 15 de março de 2014
Journals: Neotropical Biology and Conservation
Neotropical Biology and Conservation
-
Abreviatura: Neotrop. Biol. Conserv.
-
Qualis CAPES: B3 (Biodiversidade), B5 (Ciências Biológicas
III), C (Ciências Biológicas I e II).
- Taxa
de Publicação: Não há.
-
Idiomas: Português, Espanhol, Inglês.
- Disponibilidade:
Acesso livre a todos os artigos no site.
-
Submissão: Online, pelo sistema Open Journal System, com acesso na
home page.
A Neotropical
Biology and Conservation publica artigos de pesquisas originais nos campos
da ecologia, zoologia, botânica e conservação. Ênfase especial é dada a artigos
que desenvolvem novos conceitos em ecologia, testam teorias ecológicas,
analisam a biologia e comportamento de organismos terrestres e aquáticos, e
contribuem para a conservação da biodiversidade e ecossistemas. Artigos que
impliquem em políticas ambientais são bem-vindos. Artigos de genética
relacionados a conservação da biodiversidade também são adequados para
publicação. Em adição a pesquisas originais o periódico publica notas, revisões
e comentários científicos. A Neotropical
Biology and Conservation é uma publicação da Unisinos.
sábado, 1 de março de 2014
Variatión geográfica del zorro Lycalopex culpaeus (Mammalia, Canidae) en Chile: implicaciones taxonómicas
GUZMÁN, J.A.; D'ELÍA, G.; ORTIZ, J.C. 2009. Variatión geográfica del zorro Lycalopex culpaeus (Mammalia, Canidae) en Chile: implicaciones taxonómicas. Revista de Biología Tropical 57(1-2):421-432.
Abstract. Geographic variation of the fox Lycalopex culpaeus (Mammalia, Canidae) in Chile: taxonomic implications. We studied the geographic variation of skulls of Lycalopex culpaeus using qualitative and quantative analyses. The sampling area covered Chile, from its northern portion, to Tierra del Fuego and the neighbouring Hoste Island, as well as part of Argentina. Five subespecies are currently recognized from this large area. We found two morphotypes that are segregated geographically. Both groups mostly differ by morphometric attributes, followed by qualitative features. Specimens from northern Chile (Tarapacá and Antofagasta) have small skulls, short rostrum, a liriform sagital zone, and lack the interparietal crest. The second group is formed by specimens from north-western and central Argentina, central-south Chile, Patagonia, and the austral islands of Tierra del Fuego and Hoste. This group presents a strong sagital crest, large rostrum, and a large skull. Our results agree with observed patterns of mitochondrial DNA variation. We propose to retain the name L. c. andinus for the populations of northern Chile and to synonymize L. c. magellanicus, L. c. lycoides, and L. c. smithersi under L. c. culpaeus.
Abstract. Geographic variation of the fox Lycalopex culpaeus (Mammalia, Canidae) in Chile: taxonomic implications. We studied the geographic variation of skulls of Lycalopex culpaeus using qualitative and quantative analyses. The sampling area covered Chile, from its northern portion, to Tierra del Fuego and the neighbouring Hoste Island, as well as part of Argentina. Five subespecies are currently recognized from this large area. We found two morphotypes that are segregated geographically. Both groups mostly differ by morphometric attributes, followed by qualitative features. Specimens from northern Chile (Tarapacá and Antofagasta) have small skulls, short rostrum, a liriform sagital zone, and lack the interparietal crest. The second group is formed by specimens from north-western and central Argentina, central-south Chile, Patagonia, and the austral islands of Tierra del Fuego and Hoste. This group presents a strong sagital crest, large rostrum, and a large skull. Our results agree with observed patterns of mitochondrial DNA variation. We propose to retain the name L. c. andinus for the populations of northern Chile and to synonymize L. c. magellanicus, L. c. lycoides, and L. c. smithersi under L. c. culpaeus.
sábado, 22 de fevereiro de 2014
Effects of fragmentation of the Atlantic forest on mammal communities in south-eastern Brazil
CHIARELLO, A.G. 1999. Effects of fragmentation of the Atlantic forest on mammal communities in south-eastern Brazil. Biological Conservation 89:71-82.
Abstract. Six Atlantic forest reserves, two large (c. 20,000 ha each), two medium-sized (c. 2,000 ha each) and two small (c. 200 ha each), located in northern Espírito Santo, south-eastern Brazil were censured for mammals from October 1994 to April 1996. Diurnal and nocturnal line-transect sampling was used for censusing mammals > 1 kg body weight, and the relative abundance of species in the six fragments was compared. The number of mammal species recorded in the reserves was strongly related to the forest area, the richest community being recorded in the two large reserves and the poorest in the two small reserves. The large reserves had a structurally more complex community, with top predators, large, terrestrial frugivores and large myrmecophages. The mammal community of the small and the medium-sized reserves was impoverished and less complex. Frugivores were numerically predominant in both large and medium-sized reserves, whereas herbivores dominated the mammal community of the small reserves, mainly through the absence of agoutis Dasyprocta leporina and the high density of maned sloth Bradypus torquatus in the two small reserves. The lack of predators and the proliferation of secondary vegetation and lianas throughout the small reserves are probably the main causes for the success of arboreal folivores there. Illegal hunting was found to reduce the encounter rates of mostly large, terrestrial frugivores such as agoutis, pacas Agouti paca, peccaries Pecari tajacu and Tayassu pecari and deer Mazama spp., and is contributing to keep the population of the surviving species low.
Abstract. Six Atlantic forest reserves, two large (c. 20,000 ha each), two medium-sized (c. 2,000 ha each) and two small (c. 200 ha each), located in northern Espírito Santo, south-eastern Brazil were censured for mammals from October 1994 to April 1996. Diurnal and nocturnal line-transect sampling was used for censusing mammals > 1 kg body weight, and the relative abundance of species in the six fragments was compared. The number of mammal species recorded in the reserves was strongly related to the forest area, the richest community being recorded in the two large reserves and the poorest in the two small reserves. The large reserves had a structurally more complex community, with top predators, large, terrestrial frugivores and large myrmecophages. The mammal community of the small and the medium-sized reserves was impoverished and less complex. Frugivores were numerically predominant in both large and medium-sized reserves, whereas herbivores dominated the mammal community of the small reserves, mainly through the absence of agoutis Dasyprocta leporina and the high density of maned sloth Bradypus torquatus in the two small reserves. The lack of predators and the proliferation of secondary vegetation and lianas throughout the small reserves are probably the main causes for the success of arboreal folivores there. Illegal hunting was found to reduce the encounter rates of mostly large, terrestrial frugivores such as agoutis, pacas Agouti paca, peccaries Pecari tajacu and Tayassu pecari and deer Mazama spp., and is contributing to keep the population of the surviving species low.
Key Words:
Atlantic forest,
Brazil,
community ecology,
conservation,
habitat ecology,
medium and large mammals,
neotropical mammals,
Neotropical region
quinta-feira, 30 de janeiro de 2014
Journals: Biota Neotropica
Biota
Neotropica
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Abreviatura: Biota Neotrop.
- Home Page: http://www.biotaneotropica.org.br/v13n1/pt/
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Qualis CAPES: B2 (Biodiversidade), B5 (Ciências Biológicas
II e III), C (Ciências Biológicas I).
- Taxa
de Publicação: Sim.
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Idiomas: Português, Espanhol, Inglês (dependendo da categoria).
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Disponibilidade: Acesso livre a todos os artigos no site.
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Submissão: Online, em sistema próprio da revista.
O periódico Biota Neotropica é editado pelo Programa BIOTA/FAPESP e publica
resultados de pesquisa original, vinculadas ou não ao programa, que abordem a
temática caracterização, conservação e uso sustentável da biodiversidade na
região Neotropical. A revista é anual, com a publicação de quatro fascículos
por ano.
O periódico publica manuscritos nas seguintes
categorias: artigos científicos (exclusivamente em inglês), inventários,
comunicações curtas (short communication, notas científicas) (exclusivamente em
inglês), revisões temáticas (exclusivamente em inglês), revisões taxonômicas e
chaves de identificação.
Trabalhos que apenas registram uma nova
ocorrência de uma ou mais espécies, em uma região onde sua presença seria
esperada, mas o registro ainda não havia sido feito, não se enquadram no escopo
da Biota Neotropica.
O periódico tem um Taxa de Publicação de R$ 40,00
(quarenta reais) por página impressa de cada estudo publicado.
sábado, 11 de janeiro de 2014
Bats (Mammalia: Chiroptera) of Mata do Paraíso research station, Viçosa, Minas Gerais, Brazil
NASCIMENTO, M.C.; STUMPP, R.; LESSA, G. 2013. Bats (Mammalia: Chiroptera) of Mata do Paraíso research station, Viçosa, Minas Gerais, Brazil. Check List 9(6):1406-1409.
Abstract. The aim of this study was to document the records of bat species collected at the Estação de Pesquisa Treinamento e Educação Ambiental (EPTEA) da Mata do Paraíso, a small fragment of Atlantic Rainforest of 200 ha in Viçosa, Minas Gerais, Brazil. Original data was obtained by capture sessions with mist nets from November 2007 to October 2008, and complemented with material from the collection database of Museu de Zoologia João Moojen, Universidade Federal de Viçosa. We found a total of 17 bat species distributed in five families at the EPTEA Mata do Paraíso.
Abstract. The aim of this study was to document the records of bat species collected at the Estação de Pesquisa Treinamento e Educação Ambiental (EPTEA) da Mata do Paraíso, a small fragment of Atlantic Rainforest of 200 ha in Viçosa, Minas Gerais, Brazil. Original data was obtained by capture sessions with mist nets from November 2007 to October 2008, and complemented with material from the collection database of Museu de Zoologia João Moojen, Universidade Federal de Viçosa. We found a total of 17 bat species distributed in five families at the EPTEA Mata do Paraíso.
sábado, 4 de janeiro de 2014
Seasonal variation of consumption of the species used as fruit source by brown howler monkeys (Alouatta clamitans) in southern Brazil
SANTOS, G.A.S.D.; BIANCHINI, E.; REIS, N.R. 2013. Seasonal variation of consumption of the species used as fruit source by brown howler monkeys (Alouatta clamitans) in southern Brazil. Biota Neotropica 13(3):148-153.
Abstract. Considering the seasonal variation of fruits availability in seasonal semideciduous forests, this study analyzed whether the richness of fruit species exploited by Alouatta clamitans is higher in the rainy period rather than the dry one. Plant species consumed were investigated by visualization and feces analysis, from July 2005 to June 2006, in a seasonal semideciduous forest fragment in Paraná state, Brazil. Ten species of fruits were consumed during the rainy period and 13 during the dry period: three were consumed exclusively during the rainy period; six exclusively during the dry period; and seven in months that covered both dry and rainy periods. The number of fruit species consumed during the rainy period was considerably lower than the expected richness. Moreover, among fruit species consumed during the rainy period, only four bear fruits mainly in this period of the year, the other species bear fruits in great part of it. Therefore, the selectivity of A. clamitans was mainly directed to species capable of providing fruits along the year, prioritizing these species even when other fruit sources are available.
Abstract. Considering the seasonal variation of fruits availability in seasonal semideciduous forests, this study analyzed whether the richness of fruit species exploited by Alouatta clamitans is higher in the rainy period rather than the dry one. Plant species consumed were investigated by visualization and feces analysis, from July 2005 to June 2006, in a seasonal semideciduous forest fragment in Paraná state, Brazil. Ten species of fruits were consumed during the rainy period and 13 during the dry period: three were consumed exclusively during the rainy period; six exclusively during the dry period; and seven in months that covered both dry and rainy periods. The number of fruit species consumed during the rainy period was considerably lower than the expected richness. Moreover, among fruit species consumed during the rainy period, only four bear fruits mainly in this period of the year, the other species bear fruits in great part of it. Therefore, the selectivity of A. clamitans was mainly directed to species capable of providing fruits along the year, prioritizing these species even when other fruit sources are available.
sábado, 28 de dezembro de 2013
Factors affecting home range size and overlap in Akodon azarae (Muridae: Sigmodontinae) in natural pasture of Argentina
PRIOTTO, J.W.; STEINMANN, A.R. 1999. Factors affecting home range size and overlap in Akodon azarae (Muridae: Sigmodontinae) in natural pasture of Argentina. Acta Theriologica 44(1):37-44.
Abstract. Differences in home range size in relation to sex, age, breeding and non-breeding periods were studied. Home range size and overlap were examined at different densities values in populations of Akodon azarae (Fischer, 1829) on railway banks in southern Córdoba Province (Argentina). The sampling was carried out between October 1994, and February 1997, using the capture-mark-recapture method. Home range size in A. azarae was determined by sex and breeding period, and it was independent of the observed density values. Home range size of males was always larger than that of females. Increase of population density during the breeding period affected the degree of intersexual overlap of home range.
Abstract. Differences in home range size in relation to sex, age, breeding and non-breeding periods were studied. Home range size and overlap were examined at different densities values in populations of Akodon azarae (Fischer, 1829) on railway banks in southern Córdoba Province (Argentina). The sampling was carried out between October 1994, and February 1997, using the capture-mark-recapture method. Home range size in A. azarae was determined by sex and breeding period, and it was independent of the observed density values. Home range size of males was always larger than that of females. Increase of population density during the breeding period affected the degree of intersexual overlap of home range.
sábado, 14 de dezembro de 2013
Karyology of the Atlantic forest rodent Juliomys (Cricetidae): a new karyotype from southern Brazil
PARESQUE, R.; CHRISTOFF, A.U.; FAGUNDES, V. 2009. Karyology of the Atlantic forest rodent Juliomys (Cricetidae): a new karyotype from southern Brazil. Genetics and Molecular Biology 32:301-305.
Abstract. Juliomys is a small rodent from the family Cricetidae which inhabits the Atlantic forest and forests from Argentina to eastern Brazil. The three species recognized so far have different karyotypes. In this paper, we describe a new karyotype with 2n = 32, FN = 48 found in Juliomys specimens from a high-altitude area in the Atlantic forest of southern Brazil. The karyotype was analyzed after G- and C-banding and silver staining of the nucleolus organizer regions (Ag-NOR) and its G-banding patterns were compared with those of the newly described species Juliomys ossitenuis (2n = 20, FN = 36). The 2n = 32 karyomorph presented peculiar features and was very different from those of the other species of the genus: J. pictipes (2n = 36, FN = 34), J. rimofrons (2n = 20, FN = 34) and J. ossitenuis (2n = 20, FN = 36). Differences were mostly due to centric and tandem fusions, pericentric inversion and loss of hetero-chromatin. The karyotype represents a powerful tool to differentiate Juliomys species and our data suggest that the karyotype described herein belongs to a new species.
Abstract. Juliomys is a small rodent from the family Cricetidae which inhabits the Atlantic forest and forests from Argentina to eastern Brazil. The three species recognized so far have different karyotypes. In this paper, we describe a new karyotype with 2n = 32, FN = 48 found in Juliomys specimens from a high-altitude area in the Atlantic forest of southern Brazil. The karyotype was analyzed after G- and C-banding and silver staining of the nucleolus organizer regions (Ag-NOR) and its G-banding patterns were compared with those of the newly described species Juliomys ossitenuis (2n = 20, FN = 36). The 2n = 32 karyomorph presented peculiar features and was very different from those of the other species of the genus: J. pictipes (2n = 36, FN = 34), J. rimofrons (2n = 20, FN = 34) and J. ossitenuis (2n = 20, FN = 36). Differences were mostly due to centric and tandem fusions, pericentric inversion and loss of hetero-chromatin. The karyotype represents a powerful tool to differentiate Juliomys species and our data suggest that the karyotype described herein belongs to a new species.
sábado, 23 de novembro de 2013
An introduction to Marmosops (Marsupialia: Didelphidae), with the description of a new species from Bolivia and notes on the taxonomy and distribution of other bolivian forms
VOOS, R.S.; TARIFA, T.; YENSEN, E. 2004. An introduction to Marmosops (Marsupialia: Didelphidae), with the description of a new species from Bolivia and notes on the taxonomy and distribution of other bolivian forms. American Museum Novitates 3466:1-40.
Abstract. In order to facilitate much-needed revisionary research on Marmosops, we summarize the currently accepted species-level taxonomy, provide full bibliographic citations for original descriptions of all 36 included nominal taxa, map their type localities, and list their type material (if known). We rediagnose the genus Marmosops, compare it with three other didelphid genera to which misidentified specimens of Marmosops have often been referred, and review the phylogenetic evidence that Marmosops is monophyletic. After describing a new species from the eastern-slope montane forest of Bolivia, we review the taxonomy of other Bolivian congeners based on morphological characters and published cytochrome-b gene sequences. Among our taxonomic results, we synonymize albiventris Tate (1931), dorothea Thomas (1911), and yungasensis Tate (1931) with M. noctivagus (Tschudi, 1845). By contrast, M. ocellatus (Tate, 1931), currently considered a synonym of dorothea, appears to be a valid species. Whereas published range maps of Bolivian species of Marmosops are demonstrably based on misidentified material and show little correspondence with known environmental factors, locality records based on specimens examined for this report make much more eco-geographic sense.
Abstract. In order to facilitate much-needed revisionary research on Marmosops, we summarize the currently accepted species-level taxonomy, provide full bibliographic citations for original descriptions of all 36 included nominal taxa, map their type localities, and list their type material (if known). We rediagnose the genus Marmosops, compare it with three other didelphid genera to which misidentified specimens of Marmosops have often been referred, and review the phylogenetic evidence that Marmosops is monophyletic. After describing a new species from the eastern-slope montane forest of Bolivia, we review the taxonomy of other Bolivian congeners based on morphological characters and published cytochrome-b gene sequences. Among our taxonomic results, we synonymize albiventris Tate (1931), dorothea Thomas (1911), and yungasensis Tate (1931) with M. noctivagus (Tschudi, 1845). By contrast, M. ocellatus (Tate, 1931), currently considered a synonym of dorothea, appears to be a valid species. Whereas published range maps of Bolivian species of Marmosops are demonstrably based on misidentified material and show little correspondence with known environmental factors, locality records based on specimens examined for this report make much more eco-geographic sense.
sábado, 2 de novembro de 2013
The historical bridge between the Amazon and the Atlantic Forest of Brazil: a study of molecular phylogeography with small mammals
COSTA, L.P. 2003. The historical bridge between the Amazon and the Atlantic Forest of Brazil: a study of molecular phylogeography with small mammals. Journal of Biogeography 30:71-86.
Abstract.
Aim. To examine how the genetic diversity of selected taxa of forest-dwelling small mammals is distributed between and within the major rain forest domains of Amazonia and Atlantic Forest and the intervening interior forests of Brazil, as inferred by the relationships between gene genealogies and geography. I also addressed the historical importance of the central Brazilian forests in connecting Amazon and Atlantic Forest populations of rodents and marsupials.
Methods. I evaluated variation in the mitochondrial cytochrome b gene to estimate the levels of sequence divergence between those taxa occurring throughout the Amazon, Atlantic Forest, and forests in the Cerrado and Caatinga regions. I inferred the hierarchical relationships between haplotypes, populations and formal taxa using the cladistic approach of maximum parsimony. I compared areas and the clades identified by superimposing cladograms on the geographical distribution of samples. The degree of concordance both in phylogeny and the depth of the nodes in these phylogenies, in addition to patterns of geographical distribution of clades, permitted me to make inferences on how, when and where the taxa differentiated.
Results. Sequence similarity is often greater between samples from the Atlantic Forest and either Amazon or central Brazilian forests than it is within each of the two rain forest domains. The Atlantic Forest clades are either not reciprocally monophyletic or are the sister group to all the other clades. There is some indication of northern and southern components in the Atlantic Forest. Given the geographical distribution of clades and the relatively deep levels of divergence, the central Brazilian area does not behave as a separate region but is complementary to either Amazon or Atlantic Forest. Patterns of area relationships differ across taxa, suggesting that different processes and ⁄or historic events affected the diversification within each lineage.
Main conclusions. The Amazon and the Atlantic forests are not exclusive in terms of their small mammal faunas; both overlap broadly with taxa occurring in gallery forests and dry forests in central Brazil. Central Brazilian forests are an integral part of the evolutionary scenario of lowland small mammals, playing an important role as present and past habitats for rain forest species. Therefore, representatives from this area should always be included in analyses of the evolutionary history of lowland rain forest faunas. The incongruence of branching patterns among areas is in agreement with recent results presented for Neotropical passerine birds and indicates that a single hypothesis of Neotropical area relationships is unlikely. These findings reinforce the idea that speciation in the Neotropics will not be explained by any single model of vicariance or climatic changes.
Abstract.
Aim. To examine how the genetic diversity of selected taxa of forest-dwelling small mammals is distributed between and within the major rain forest domains of Amazonia and Atlantic Forest and the intervening interior forests of Brazil, as inferred by the relationships between gene genealogies and geography. I also addressed the historical importance of the central Brazilian forests in connecting Amazon and Atlantic Forest populations of rodents and marsupials.
Methods. I evaluated variation in the mitochondrial cytochrome b gene to estimate the levels of sequence divergence between those taxa occurring throughout the Amazon, Atlantic Forest, and forests in the Cerrado and Caatinga regions. I inferred the hierarchical relationships between haplotypes, populations and formal taxa using the cladistic approach of maximum parsimony. I compared areas and the clades identified by superimposing cladograms on the geographical distribution of samples. The degree of concordance both in phylogeny and the depth of the nodes in these phylogenies, in addition to patterns of geographical distribution of clades, permitted me to make inferences on how, when and where the taxa differentiated.
Results. Sequence similarity is often greater between samples from the Atlantic Forest and either Amazon or central Brazilian forests than it is within each of the two rain forest domains. The Atlantic Forest clades are either not reciprocally monophyletic or are the sister group to all the other clades. There is some indication of northern and southern components in the Atlantic Forest. Given the geographical distribution of clades and the relatively deep levels of divergence, the central Brazilian area does not behave as a separate region but is complementary to either Amazon or Atlantic Forest. Patterns of area relationships differ across taxa, suggesting that different processes and ⁄or historic events affected the diversification within each lineage.
Main conclusions. The Amazon and the Atlantic forests are not exclusive in terms of their small mammal faunas; both overlap broadly with taxa occurring in gallery forests and dry forests in central Brazil. Central Brazilian forests are an integral part of the evolutionary scenario of lowland small mammals, playing an important role as present and past habitats for rain forest species. Therefore, representatives from this area should always be included in analyses of the evolutionary history of lowland rain forest faunas. The incongruence of branching patterns among areas is in agreement with recent results presented for Neotropical passerine birds and indicates that a single hypothesis of Neotropical area relationships is unlikely. These findings reinforce the idea that speciation in the Neotropics will not be explained by any single model of vicariance or climatic changes.
sábado, 26 de outubro de 2013
The maned wolf in the ecotone between forest and grasslands at the limits of its distribution in a subtropical environment
MARQUES, R.V.; FABIÁN, M.E. 2013. The maned wolf in the ecotone between forest and grasslands at the limits of its distribution in a subtropical environment. Bioscience Journal 29(3):751-759.
Abstract. The maned wolf (Chrysocyon brachyurus) is a neotropical canid that is considered near threatened by the IUCN, vulnerable in Brazil and critically endangered in the state of Rio Grande do Sul. The Araucaria High Plains have coverage of Atlantic forest mixed in with open areas and small wetland areas and are at one of the limits of the range of the maned wolf. The objectives of this article are to demonstrate that, although rare, the maned wolf does still occur in the Araucaria High Plains and to discuss the relevance of conservation efforts in areas in which the occurrence of threatened species is borderline. Data collection took place between March of 1999 and December of 2010 with a total sampling effort of 11,431 trap-days. After 10 years in which there were no corroborated records, the species was caught by camera traps in the São Francisco de Paula National Forest in November of 2009. This is a protected area with forest vegetation and is not considered the species’ typical habitat. The open areas in this region are being taken over by agriculture and silviculture of exotic species.
Abstract. The maned wolf (Chrysocyon brachyurus) is a neotropical canid that is considered near threatened by the IUCN, vulnerable in Brazil and critically endangered in the state of Rio Grande do Sul. The Araucaria High Plains have coverage of Atlantic forest mixed in with open areas and small wetland areas and are at one of the limits of the range of the maned wolf. The objectives of this article are to demonstrate that, although rare, the maned wolf does still occur in the Araucaria High Plains and to discuss the relevance of conservation efforts in areas in which the occurrence of threatened species is borderline. Data collection took place between March of 1999 and December of 2010 with a total sampling effort of 11,431 trap-days. After 10 years in which there were no corroborated records, the species was caught by camera traps in the São Francisco de Paula National Forest in November of 2009. This is a protected area with forest vegetation and is not considered the species’ typical habitat. The open areas in this region are being taken over by agriculture and silviculture of exotic species.
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