Mostrando postagens com marcador habitat ecology. Mostrar todas as postagens
Mostrando postagens com marcador habitat ecology. Mostrar todas as postagens
quarta-feira, 10 de junho de 2015
sábado, 16 de maio de 2015
Treetop shelter of a Neotropical River Otter cuba (Lontra longicaudis - Carnivora: Mustelidae) in an Amazonian flooded forest
SANTOS, P.M.R.S.; KINUPP, V.F.; COLETTO-SILVA, A. 2007. Treetop shelter of a Neotropical River Otter cuba (Lontra longicaudis - Carnivora: Mustelidae) in an Amazonian flooded forest. Acta Amazonica 37(2):309-312.
Abstract. The finding of a Neotropical river otter (Lontra longicaudis) cub occupying a shelter in a hollowed treetop is reported. The observation was made in a seasonally flooded forest in Central Amazonia, during the high water peak of the annual inundation cycle. A literature review indicates that this is the first description of a shelter of the species, both in a hollowed tree and in Amazonia. This observation can indicate a strong relationship between the species’ breeding cycle with the annual dynamics of Amazonian rivers. We discuss potential advantages and disadvantages of breeding when water level is high.
Abstract. The finding of a Neotropical river otter (Lontra longicaudis) cub occupying a shelter in a hollowed treetop is reported. The observation was made in a seasonally flooded forest in Central Amazonia, during the high water peak of the annual inundation cycle. A literature review indicates that this is the first description of a shelter of the species, both in a hollowed tree and in Amazonia. This observation can indicate a strong relationship between the species’ breeding cycle with the annual dynamics of Amazonian rivers. We discuss potential advantages and disadvantages of breeding when water level is high.
sábado, 5 de julho de 2014
Use of arboreal and terrestrial space by a small mammal community in a tropical rain forest in Borneo, Malaysia
WELLS, K. PFEIFFER, M.; LAKIM, M.B.; LINSENMAIR, K.E. 2004. Use of arboreal and terrestrial space by a small mammal community in a tropical rain forest in Borneo, Malaysia. Journal of Biogeography 31:641-652.
Abstract:
Aim: Small mammals were live-trapped in a primary rain forest to evaluate the relative distribution of species to each other and to microhabitat properties on the ground and in the canopy.
Location: Kinabalu National Park in Borneo, Sabah, Malaysia.
Methods: Seven trapping sessions were conducted along two grids with 31 trap points at distances of 20 m on the ground and in the lower canopy at an average height of 13.5 m.
Results: Species diversity and abundance of small mammals proved to be high: 20 species of the families Muridae, Sciuridae, Tupaiidae, Hystricidae, Viverridae and Lorisidae were trapped, with murids being dominant in both habitat layers. The terrestrial community was significantly more diverse with 16 captured species (Shannon–Wiener’s diversity index H'terr = 2.47), while 11 species were trapped in the canopy (H'arb = 1.59). The Whitehead’s rat, Maxomys whiteheadi, and the red spiny rat, Maxomys surifer, dominated the terrestrial community whereas the large pencil-tailed tree mouse, Chiropodomys major, was by far the most abundant species in the canopy. Other abundant species of the canopy community, the dark-tailed tree rat, Niviventer cremoriventer, and the lesser treeshrew, Tupaia minor, were also abundant on the ground, and there was no clear boundary between arboreal and terrestrial species occurrences.
Main Conclusions: As most species were not confined to specific microhabitats or habitat layers, species seemed to rely on resources not necessarily restricted to certain microhabitats or habitat layers, and separation of species probably resulted mainly from a species’ concentrated activity in a preferred microhabitat rather than from principal adaptations to certain habitats. Ecological segregation was stronger in the more diverse terrestrial community, though microhabitat selection was generally not sufficient to explain the co-occurrences of species and the variability between local species assemblages. Constraints on small mammal foraging efficiency in the three-dimensional more complex canopy may be responsible for the similarity of microhabitat use of all common arboreal species. Community composition was characterized by mobile species with low persistence rates, resulting in a high degree of variability in local species assemblages with similar turnover rates in both habitats.
Abstract:
Aim: Small mammals were live-trapped in a primary rain forest to evaluate the relative distribution of species to each other and to microhabitat properties on the ground and in the canopy.
Location: Kinabalu National Park in Borneo, Sabah, Malaysia.
Methods: Seven trapping sessions were conducted along two grids with 31 trap points at distances of 20 m on the ground and in the lower canopy at an average height of 13.5 m.
Results: Species diversity and abundance of small mammals proved to be high: 20 species of the families Muridae, Sciuridae, Tupaiidae, Hystricidae, Viverridae and Lorisidae were trapped, with murids being dominant in both habitat layers. The terrestrial community was significantly more diverse with 16 captured species (Shannon–Wiener’s diversity index H'terr = 2.47), while 11 species were trapped in the canopy (H'arb = 1.59). The Whitehead’s rat, Maxomys whiteheadi, and the red spiny rat, Maxomys surifer, dominated the terrestrial community whereas the large pencil-tailed tree mouse, Chiropodomys major, was by far the most abundant species in the canopy. Other abundant species of the canopy community, the dark-tailed tree rat, Niviventer cremoriventer, and the lesser treeshrew, Tupaia minor, were also abundant on the ground, and there was no clear boundary between arboreal and terrestrial species occurrences.
Main Conclusions: As most species were not confined to specific microhabitats or habitat layers, species seemed to rely on resources not necessarily restricted to certain microhabitats or habitat layers, and separation of species probably resulted mainly from a species’ concentrated activity in a preferred microhabitat rather than from principal adaptations to certain habitats. Ecological segregation was stronger in the more diverse terrestrial community, though microhabitat selection was generally not sufficient to explain the co-occurrences of species and the variability between local species assemblages. Constraints on small mammal foraging efficiency in the three-dimensional more complex canopy may be responsible for the similarity of microhabitat use of all common arboreal species. Community composition was characterized by mobile species with low persistence rates, resulting in a high degree of variability in local species assemblages with similar turnover rates in both habitats.
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, 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.
sábado, 7 de dezembro de 2013
Use of vertical space by small mammals in gallery forest and woodland savannah in south-western Brazil
HANNIBAL W.; CÁCERES NC. 2010. Use of vertical space by small mammals in gallery forest and woodland savannah in south-western Brazil. Mammalia 74: 247-255. doi: 10.1515/MAMM.2010.007
Abstract. We examined the community composition and abundance of small mammals in the vertical strata of gallery forests and woodland savannahs in south-western Brazil. Captures were carried out during the winter and summer months of 2006/2007. Traps were set in three transect lines per habitat, with 10 capture stations on each line. Each station had three traps: on the ground, in the understorey (2–3 m in height), and in the canopy (8–10 m) in each physiognomy. With an effort of 3600 trap-nights, 11 species of small mammals were captured, which were distributed differently regarding the forest physiognomies and utilisation of vertical strata. The species showed a high degree of habitat segregation in the two physiognomies, with only the climbing-rat Rhipidomys macrurus found in both habitats. The correspondence analysis revealed that Caluromys philander occurred mostly in the canopy; Cryptonanus agricolai, Marmosa murina, and Oecomys bicolor in the understorey; and Gracilinanus agilis and Nectomys rattus on the ground. The utilisation of traps in different strata increased species richness in the Cerrado biome, showing that the small-mammal community is distributed along the vertical complexity of the forest and even in different physiognomies, enabling more species to coexist.
Abstract. We examined the community composition and abundance of small mammals in the vertical strata of gallery forests and woodland savannahs in south-western Brazil. Captures were carried out during the winter and summer months of 2006/2007. Traps were set in three transect lines per habitat, with 10 capture stations on each line. Each station had three traps: on the ground, in the understorey (2–3 m in height), and in the canopy (8–10 m) in each physiognomy. With an effort of 3600 trap-nights, 11 species of small mammals were captured, which were distributed differently regarding the forest physiognomies and utilisation of vertical strata. The species showed a high degree of habitat segregation in the two physiognomies, with only the climbing-rat Rhipidomys macrurus found in both habitats. The correspondence analysis revealed that Caluromys philander occurred mostly in the canopy; Cryptonanus agricolai, Marmosa murina, and Oecomys bicolor in the understorey; and Gracilinanus agilis and Nectomys rattus on the ground. The utilisation of traps in different strata increased species richness in the Cerrado biome, showing that the small-mammal community is distributed along the vertical complexity of the forest and even in different physiognomies, enabling more species to coexist.
sábado, 16 de novembro de 2013
Rural roads as barriers to the movements of small mammals
MACPHERSON, D.; MACPHERSON, J.L.; MORRIS, P. 2011. Rural roads as barriers to the movements of small mammals. Applied Ecology and Environmental Research 9(2):167-180.
Abstract. Over the last 50 years increasing fragmentation of habitats has occurred due to road building. Fragmenting a large population into smaller ones can have a negative effect on population demography. In England much small mammal habitat occurs in suburban and rural areas where the majority of roads are either single track or two lanes, and traffic density is light. This study investigated the effect of minor roads on the movements of two small mammals, the wood mouse (Apodemus sylvaticus) and bank vole (Myodes glareolus). Capture-Mark-Recapture was used to study movements beside and across rural roads of two different widths. The results suggest that even small roads less than 6metres wide, with relatively little traffic, do act as partial barriers for these small mammals, reducing their movement between habitats on either side of the road. It is evident that island populations are being created as a result of road construction, even access roads within nature reserves.
Abstract. Over the last 50 years increasing fragmentation of habitats has occurred due to road building. Fragmenting a large population into smaller ones can have a negative effect on population demography. In England much small mammal habitat occurs in suburban and rural areas where the majority of roads are either single track or two lanes, and traffic density is light. This study investigated the effect of minor roads on the movements of two small mammals, the wood mouse (Apodemus sylvaticus) and bank vole (Myodes glareolus). Capture-Mark-Recapture was used to study movements beside and across rural roads of two different widths. The results suggest that even small roads less than 6metres wide, with relatively little traffic, do act as partial barriers for these small mammals, reducing their movement between habitats on either side of the road. It is evident that island populations are being created as a result of road construction, even access roads within nature reserves.
sábado, 12 de outubro de 2013
Microhabitat of small mammals at ground and understorey levels in a deciduous, southern Atlantic Forest
MELO, G.L.; MIOTTO, B.; PERES, B.; CÁCERES, N.C. 2013. Microhabitat of small mammals at ground and understorey levels in a deciduous, southern Atlantic Forest. Anais da Academia Brasileira de Ciências 85(2):727-736.
Abstract. Each animal species selects specific microhabitats for protection, foraging, or micro-climate. To understand the distribution patterns of small mammals on the ground and in the understorey, we investigated the use of microhabitats by small mammals in a deciduous forest of southern Brazil. Ten trap stations with seven capture points were used to sample the following microhabitats: liana, fallen log, ground litter, terrestrial ferns, simple-trunk tree, forked tree, and Piper sp. shrubs. Seven field phases were conducted, each for eight consecutive days, from September 2006 through January 2008. Four species of rodents (Akodon montensis, Sooretamys angouya, Oligoryzomys nigripes and Mus musculus) and two species of marsupials (Didelphis albiventris and Gracilinanus microtarsus) were captured. Captured species presented significant differences on their microhabitat use (ANOVA, p = 0.003), particularly between ground and understorey sites. Akodon montensis selected positively terrestrial ferns and trunks, S. angouya selected lianas, D. albiventris selected fallen trunks and Piper sp., and G. microtarsus choose tree trunks and lianas. We demonstrated that the local small-mammal assemblage does select microhabitats, with different types of associations between species and habitats. Besides, there is a strong evidence of habitat selection in order to diminish predation.
Abstract. Each animal species selects specific microhabitats for protection, foraging, or micro-climate. To understand the distribution patterns of small mammals on the ground and in the understorey, we investigated the use of microhabitats by small mammals in a deciduous forest of southern Brazil. Ten trap stations with seven capture points were used to sample the following microhabitats: liana, fallen log, ground litter, terrestrial ferns, simple-trunk tree, forked tree, and Piper sp. shrubs. Seven field phases were conducted, each for eight consecutive days, from September 2006 through January 2008. Four species of rodents (Akodon montensis, Sooretamys angouya, Oligoryzomys nigripes and Mus musculus) and two species of marsupials (Didelphis albiventris and Gracilinanus microtarsus) were captured. Captured species presented significant differences on their microhabitat use (ANOVA, p = 0.003), particularly between ground and understorey sites. Akodon montensis selected positively terrestrial ferns and trunks, S. angouya selected lianas, D. albiventris selected fallen trunks and Piper sp., and G. microtarsus choose tree trunks and lianas. We demonstrated that the local small-mammal assemblage does select microhabitats, with different types of associations between species and habitats. Besides, there is a strong evidence of habitat selection in order to diminish predation.
sábado, 5 de outubro de 2013
Support diameter, incline, and vertical movements of four didelphid marsupials in the Atlantic forest of Brazil
CUNHA, A.A.; VIEIRA, M.V. 2002. Support diameter, incline, and vertical movements of four didelphid marsupials in the Atlantic forest of Brazil. Journal of Zoology, London 258:419-426.
Abstract. Didelphids use vertical strata in different ways, suggesting the existence of a wider variety of niches than simply arboreal or terrestrial. This variety could be related to the differential ability to deal with support diameters and inclines, and might be important for the coexistence of species in local assemblages. From data obtained with the spool-and-line technique, the use of the vertical space and above-ground supports is described in four species of an assemblage of didelphid marsupials in south-east Brazil. The stratification in this and other assemblages in the Atlantic forest and in the Amazon is also compared. Animals were trapped in Serra dos Órgãos, state of Rio de Janeiro, and equipped with a spool-and-line device before release. The paths were tracked by measuring variables related to support diameter, incline, distance and height moved above ground. The diameter of supports used was positively related to body size, and the incline to the dominant direction of movement (horizontal vs vertical). The more cursorial species, Metachirus nudicaudatus, only once moved above ground in > 3200 m of paths followed. Didelphis aurita moved mostly on the ground, but was the only species that occasionally reached the canopy. Philander frenata also moved mostly on the ground, occasionally used the understorey, but never reached the canopy. The more arboreal species, Marmosops incanus, moved mostly in the understorey, but never in the canopy. This pattern of stratification is similar to that observed in other sites in the Atlantic forest and in the Amazon.
Abstract. Didelphids use vertical strata in different ways, suggesting the existence of a wider variety of niches than simply arboreal or terrestrial. This variety could be related to the differential ability to deal with support diameters and inclines, and might be important for the coexistence of species in local assemblages. From data obtained with the spool-and-line technique, the use of the vertical space and above-ground supports is described in four species of an assemblage of didelphid marsupials in south-east Brazil. The stratification in this and other assemblages in the Atlantic forest and in the Amazon is also compared. Animals were trapped in Serra dos Órgãos, state of Rio de Janeiro, and equipped with a spool-and-line device before release. The paths were tracked by measuring variables related to support diameter, incline, distance and height moved above ground. The diameter of supports used was positively related to body size, and the incline to the dominant direction of movement (horizontal vs vertical). The more cursorial species, Metachirus nudicaudatus, only once moved above ground in > 3200 m of paths followed. Didelphis aurita moved mostly on the ground, but was the only species that occasionally reached the canopy. Philander frenata also moved mostly on the ground, occasionally used the understorey, but never reached the canopy. The more arboreal species, Marmosops incanus, moved mostly in the understorey, but never in the canopy. This pattern of stratification is similar to that observed in other sites in the Atlantic forest and in the Amazon.
sábado, 24 de agosto de 2013
Activity patterns of the culpeo fox (Lycalopex culpaeus megellanica) in a non-hunting area of northwestern Patagonia, Argentina
MONTEVERDE, M.J.; PIUDO, L. 2011. Activity patterns of the culpeo fox (Lycalopex culpaeus megellanica) in a non-hunting area of northwestern Patagonia, Argentina. Mammal Study 36:119-125.
Abstract. The culpeo fox is the largest native canid in Patagonia. The majority of past studies on culpeo foxes have focused on trophic ecology, population dynamics, natural history, competitive interactions, management, and habitat use. Little work has been done on determining activity patterns of the fox and thus, conclusions regarding culpeo fox activity patterns have been based on limited data. The objective of our study was to determine culpeo fox activity patterns in a protected area (Lanín National Park, Argentina) using “camera-traps” to test the hypothesis that the culpeo fox is still nocturnal in non-hunting areas. Data were collected from October 2008 through May 2009 at 29 infrared triggered camera stations. We obtained 1,261 culpeo fox photos of which 234 were used for analyses. Diet was studied from 34 culpeo fox scats. Culpeo foxes were most active during nighttime (>70% of the records) confirming the general patterns obtained in other studies. Additionally, examination of culpeo fox scats revealed that they mostly preyed on nocturnal small mammals. The present study offers evidence against the widespread assumption that nocturnal activity of this species is a behavioral response to human harassment, as it was conducted in a protected area where culpeo foxes are not hunted. Instead, their nocturnal behavior may be related to prey activity patterns.
Abstract. The culpeo fox is the largest native canid in Patagonia. The majority of past studies on culpeo foxes have focused on trophic ecology, population dynamics, natural history, competitive interactions, management, and habitat use. Little work has been done on determining activity patterns of the fox and thus, conclusions regarding culpeo fox activity patterns have been based on limited data. The objective of our study was to determine culpeo fox activity patterns in a protected area (Lanín National Park, Argentina) using “camera-traps” to test the hypothesis that the culpeo fox is still nocturnal in non-hunting areas. Data were collected from October 2008 through May 2009 at 29 infrared triggered camera stations. We obtained 1,261 culpeo fox photos of which 234 were used for analyses. Diet was studied from 34 culpeo fox scats. Culpeo foxes were most active during nighttime (>70% of the records) confirming the general patterns obtained in other studies. Additionally, examination of culpeo fox scats revealed that they mostly preyed on nocturnal small mammals. The present study offers evidence against the widespread assumption that nocturnal activity of this species is a behavioral response to human harassment, as it was conducted in a protected area where culpeo foxes are not hunted. Instead, their nocturnal behavior may be related to prey activity patterns.
sábado, 17 de agosto de 2013
The role of forest structure, fragment size and corridors in maintaining small mammal abundance and diversity in an Atlantic forest landscape
PARDINI, R.; SOUZA, S.M.; BRAGA-NETO, R.; METZGER, J.P. 2005. The role of forest structure, fragment size and corridors in maintaining small mammal abundance and diversity in an Atlantic forest landscape. Biological Conservation 124:253-266. doi:10.1016/j.biocon.2005.01.033.
Abstract. Using the abundance and distribution of small mammals at 26 sites in an Atlantic forest landscape, we investigated how species abundance and alpha and beta diversity are affected by fragment size and the presence of corridors. To account for the variability in forest structure among fragments, we described and minimized the influence of foliage density and stratification on small mammal data. Sites were distributed among three categories of fragment size and in continuous forest. For small and medium-sized categories, we considered isolated fragments and fragments connected by corridors to larger remnants. Small mammal abundance and alpha and beta diversity were regressed against site scores from the first axis of a Principal Component Analysis on forest structure variables. Residuals were used in analyses of variance to compare fragment size and connectivity categories. Forest structure influenced total abundance and abundance of some species individually, but not the diversity of small mammal communities. Total abundance and alpha diversity were lower in small and medium-sized fragments than in large fragments and continuous forest, and in isolated compared to connected fragments. Three species were less common, but none was more abundant in smaller fragments. At least one species was more abundant in connected compared to isolated fragments. Beta diversity showed an opposite relationship to fragment size and corridors, increasing in small and isolated fragments. Results highlight the importance of secondary forest for the conservation of tropical fauna, the hyper-dynamism of small isolated fragments and the potential of corridors to buffer habitat fragmentation effects in tropical landscapes.
Abstract. Using the abundance and distribution of small mammals at 26 sites in an Atlantic forest landscape, we investigated how species abundance and alpha and beta diversity are affected by fragment size and the presence of corridors. To account for the variability in forest structure among fragments, we described and minimized the influence of foliage density and stratification on small mammal data. Sites were distributed among three categories of fragment size and in continuous forest. For small and medium-sized categories, we considered isolated fragments and fragments connected by corridors to larger remnants. Small mammal abundance and alpha and beta diversity were regressed against site scores from the first axis of a Principal Component Analysis on forest structure variables. Residuals were used in analyses of variance to compare fragment size and connectivity categories. Forest structure influenced total abundance and abundance of some species individually, but not the diversity of small mammal communities. Total abundance and alpha diversity were lower in small and medium-sized fragments than in large fragments and continuous forest, and in isolated compared to connected fragments. Three species were less common, but none was more abundant in smaller fragments. At least one species was more abundant in connected compared to isolated fragments. Beta diversity showed an opposite relationship to fragment size and corridors, increasing in small and isolated fragments. Results highlight the importance of secondary forest for the conservation of tropical fauna, the hyper-dynamism of small isolated fragments and the potential of corridors to buffer habitat fragmentation effects in tropical landscapes.
sábado, 20 de julho de 2013
Do invasive fire ants affect habitat selection within a small mammal community?
HOLTCAMP, W.N.; WILLIAMS, C.K.; GRANT, W.E. 2010. Do invasive fire ants affect habitat selection within a small mammal community? International Journal of Ecology, v. 2010, Article ID 642412, 7 pages. doi: 10.1155/2011/642412.
Abstract. Animals must balance foraging with the need to avoid predators and risky habitats that decrease their fitness, and at the same time they must cope with competitors vying for habitat and resources. We examined how habitat selection and population density of four native small mammals were altered by the presence of red imported fire ants (Solenopsis invicta). When population size was low, hispid cotton rats (Sigmodon hispidus) and pigmy mice (Baiomys taylori) as well as white-footedmice (Peromyscus leucopus) used the “safe”, low fire ant habitat, as predicted by theories of density-dependent habitat selection. However, as fire ant population sizes expanded, cotton rats appeared to displace pigmy mice into the fire ant-dense grassland drainage while white-footed mice (Peromyscus leucopus) displaced all the other small mammals from low fire ant forest/brushland habitat.
Abstract. Animals must balance foraging with the need to avoid predators and risky habitats that decrease their fitness, and at the same time they must cope with competitors vying for habitat and resources. We examined how habitat selection and population density of four native small mammals were altered by the presence of red imported fire ants (Solenopsis invicta). When population size was low, hispid cotton rats (Sigmodon hispidus) and pigmy mice (Baiomys taylori) as well as white-footedmice (Peromyscus leucopus) used the “safe”, low fire ant habitat, as predicted by theories of density-dependent habitat selection. However, as fire ant population sizes expanded, cotton rats appeared to displace pigmy mice into the fire ant-dense grassland drainage while white-footed mice (Peromyscus leucopus) displaced all the other small mammals from low fire ant forest/brushland habitat.
sábado, 13 de julho de 2013
Activity, habitat use, density, and reproductive biology of the crab-eating fox (Cerdocyon thous) and comparison with the pampas fox (Lycalopex gymnocercus) in a Restinga area in the southern Brazilian Atlantic Forest
FARIA-CORRÊA, M.; BALBUENO, R.A.; VIEIRA, E.M.; FREITAS, T.R.O. 2009. Activity, habitat use, density, and reproductive biology of the crab-eating fox (Cerdocyon thous) and comparison with the pampas fox (Lycalopex gymnocercus) in a Restinga area in the southern Brazilian Atlantic Forest. Mammalian Biology 74:220-229.
Abstract. The ecology and reproductive biology of the crab-eating fox (Cerdocyon thous) and the pampas fox (Lycalopex gymnocercus) were studied in Itapuã State Park, an Atlantic Forest fragment. In this study we describe their activity patterns (diel, lunar, and seasonal), reproductive period, density, spatial distribution, and habitat overlap. The crab-eating fox was more abundant than the pampas fox, occurring in all types of habitats and overlapping with the pampas fox only in the southern portion of the study area, covered by open vegetation. Both canid species presented nocturnal habits and C. thous showed no significant differences in activity among lunar phases or else year season. The density of C. thous was estimated to be 0.78 ind/km². The crab-eating fox reproduced once a year, generating pups during spring (October to December). In comparison with C. thous populations from lower-latitude regions the relatively low density and one reproductive event per year that we observed are probably related to a colder climate, shorter photoperiod, and shortage of food resources in the winter, characteristic of southern Brazil.
Abstract. The ecology and reproductive biology of the crab-eating fox (Cerdocyon thous) and the pampas fox (Lycalopex gymnocercus) were studied in Itapuã State Park, an Atlantic Forest fragment. In this study we describe their activity patterns (diel, lunar, and seasonal), reproductive period, density, spatial distribution, and habitat overlap. The crab-eating fox was more abundant than the pampas fox, occurring in all types of habitats and overlapping with the pampas fox only in the southern portion of the study area, covered by open vegetation. Both canid species presented nocturnal habits and C. thous showed no significant differences in activity among lunar phases or else year season. The density of C. thous was estimated to be 0.78 ind/km². The crab-eating fox reproduced once a year, generating pups during spring (October to December). In comparison with C. thous populations from lower-latitude regions the relatively low density and one reproductive event per year that we observed are probably related to a colder climate, shorter photoperiod, and shortage of food resources in the winter, characteristic of southern Brazil.
sábado, 16 de fevereiro de 2013
Modeling impacts of climate change on giant panda habitat
SONGER, M.; DELION, M.; BIGGS, A.; HUANG, Q. 2012. Modeling impacts of climate change on giant panda habitat. International Journal of Ecology, v 2012, Article ID 108752, 12 pages. doi: 10.1155/2012/108752.
Abstract. Giant pandas (Ailuropoda melanoleuca) are one of the most widely recognized endangered species globally. Habitat loss and fragmentation are the main threats, and climate change could significantly impact giant panda survival.We integrated giant panda habitat information with general climate models (GCMs) to predict future geographic distribution and fragmentation of giant panda habitat. Results support a major general prediction of climate change—a shift of habitats towards higher elevation and higher latitudes. Our models predict climate change could reduce giant panda habitat by nearly 60% over 70 years. New areas may become suitable outside the current geographic range but much of these areas is far from the current giant panda range and only 15% fall within the current protected area system. Long-term survival of giant pandas will require the creation of new protected areas that are likely to support suitable habitat even if the climate changes.
Abstract. Giant pandas (Ailuropoda melanoleuca) are one of the most widely recognized endangered species globally. Habitat loss and fragmentation are the main threats, and climate change could significantly impact giant panda survival.We integrated giant panda habitat information with general climate models (GCMs) to predict future geographic distribution and fragmentation of giant panda habitat. Results support a major general prediction of climate change—a shift of habitats towards higher elevation and higher latitudes. Our models predict climate change could reduce giant panda habitat by nearly 60% over 70 years. New areas may become suitable outside the current geographic range but much of these areas is far from the current giant panda range and only 15% fall within the current protected area system. Long-term survival of giant pandas will require the creation of new protected areas that are likely to support suitable habitat even if the climate changes.
sábado, 9 de fevereiro de 2013
Conservation strategy for brown bear and its habitat in Nepal
ARYAL, A.; RAUBENHEIMER, D.; SATHYAKUMAR, S.; POUDEL, B.S.; JI, W.; KUNWAR, K.J.; KOK, J.; KOHSHIMA, S.; BRUNTON, D. 2012. Conservation strategy for brown bear and its habitat in Nepal. Diversity 4(3):301-317. doi: 10.3390/d4030301.
Abstract. The Himalaya region of Nepal encompasses significant habitats for several endangered species, among them the brown bear (Ursus arctos pruinosus). However, owing to the remoteness of the region and a dearth of research, knowledge on the conservation status, habitat and population size of this species is lacking. Our aim in this paper is to report a habitat survey designed to assess the distribution and habitat characteristics of the brown bear in the Nepalese Himalaya, and to summarize a conservation action plan for the species devised at a pair of recent workshops held in Nepal. Results of our survey showed that brown bear were potentially distributed between 3800 m and 5500 m in the high mountainous region of Nepal, across an area of 4037 km2 between the eastern border of Shey Phoksundo National Park (SPNP) and the Manasalu Conservation Area (MCA). Of that area, 2066 km2 lie inside the protected area (350 km2 in the MCA; 1716 km2 in the Annapurna Conservation Area) and 48% (1917 km2) lies outside the protected area in the Dolpa district. Furthermore, 37% of brown bear habitat also forms a potential habitat for blue sheep (or bharal, Pseudois nayaur), and 17% of these habitats is used by livestock, suggesting a significant potential for resource competition. Several plant species continue to be uprooted by local people for fuel wood. Based on the results of our field survey combined with consultations with local communities and scientists, we propose that government and non-government organizations should implement a three-stage program of conservation activities for the brown bear. This program should: (a) Detail research activities in and outside the protected area of Nepal; (b) support livelihood and conservation awareness at local and national levels; and (c) strengthen local capacity and reduce human-wildlife conflict in the region.
brown bear; Nepal; Annapurna; habitat overlap; livestock; blue sheep
Abstract. The Himalaya region of Nepal encompasses significant habitats for several endangered species, among them the brown bear (Ursus arctos pruinosus). However, owing to the remoteness of the region and a dearth of research, knowledge on the conservation status, habitat and population size of this species is lacking. Our aim in this paper is to report a habitat survey designed to assess the distribution and habitat characteristics of the brown bear in the Nepalese Himalaya, and to summarize a conservation action plan for the species devised at a pair of recent workshops held in Nepal. Results of our survey showed that brown bear were potentially distributed between 3800 m and 5500 m in the high mountainous region of Nepal, across an area of 4037 km2 between the eastern border of Shey Phoksundo National Park (SPNP) and the Manasalu Conservation Area (MCA). Of that area, 2066 km2 lie inside the protected area (350 km2 in the MCA; 1716 km2 in the Annapurna Conservation Area) and 48% (1917 km2) lies outside the protected area in the Dolpa district. Furthermore, 37% of brown bear habitat also forms a potential habitat for blue sheep (or bharal, Pseudois nayaur), and 17% of these habitats is used by livestock, suggesting a significant potential for resource competition. Several plant species continue to be uprooted by local people for fuel wood. Based on the results of our field survey combined with consultations with local communities and scientists, we propose that government and non-government organizations should implement a three-stage program of conservation activities for the brown bear. This program should: (a) Detail research activities in and outside the protected area of Nepal; (b) support livelihood and conservation awareness at local and national levels; and (c) strengthen local capacity and reduce human-wildlife conflict in the region.
brown bear; Nepal; Annapurna; habitat overlap; livestock; blue sheep
sábado, 19 de janeiro de 2013
Microhabitats in a forest-floor small mammal fauna
DUESER, R.D.; SHUGART JR., H.H. 1978. Microhabitats in a forest-floor small mammal fauna. Ecology 59(1):89-98.
Abstract. This study examines microhabitat configurations for 3 small mammal species occupying second-growth mesic forest on Walker Branch Watershed in eastern Tennessee. Small mammal populations were sampled in oak-hickory, chestnut oak and pine forest types, with three 0.36-ha live-trapping grids per forest type. There were 255 total captures for 4 forest-floor species during 9,696 trap-nights between 1 May and 16 August 1973. These captures included 2% Blarina brevicauda, 66% Peromyscus leucopus, 5% Ochrotomys nuttalli and 27% Tamias striatus. Blarina was captured most frequently in the pine forest type, Peromyscus and Tamias most frequently in the oak-hickory, and Ochrotomys exclusively in the pine. Twenty-nine variables describing proximate habitat structure were measured at each small mammal capture site. There were significant overall species differences on 18 of these variables. A subset of variables was identified for each of the 3 most frequently observed species, consisting of only the variables of particular significance for distinguishing the capture sites of that species from those of the other species collectively. Discriminant analysis of these few variables both described the average microhabitat configuration for a species and indicated the relative importance of each variable for characterizing or describing that configuration, subject to the assumptions of the analysis. The observed differences between species in microhabitat configuration are consistent with both the composition by forest type of each species sample and the literature information for each species. Microhabitat segregation among these species is discussed with reference to recent theories of habitat selection, ecological specialization and resource partitioning in equilibrium faunas.
Abstract. This study examines microhabitat configurations for 3 small mammal species occupying second-growth mesic forest on Walker Branch Watershed in eastern Tennessee. Small mammal populations were sampled in oak-hickory, chestnut oak and pine forest types, with three 0.36-ha live-trapping grids per forest type. There were 255 total captures for 4 forest-floor species during 9,696 trap-nights between 1 May and 16 August 1973. These captures included 2% Blarina brevicauda, 66% Peromyscus leucopus, 5% Ochrotomys nuttalli and 27% Tamias striatus. Blarina was captured most frequently in the pine forest type, Peromyscus and Tamias most frequently in the oak-hickory, and Ochrotomys exclusively in the pine. Twenty-nine variables describing proximate habitat structure were measured at each small mammal capture site. There were significant overall species differences on 18 of these variables. A subset of variables was identified for each of the 3 most frequently observed species, consisting of only the variables of particular significance for distinguishing the capture sites of that species from those of the other species collectively. Discriminant analysis of these few variables both described the average microhabitat configuration for a species and indicated the relative importance of each variable for characterizing or describing that configuration, subject to the assumptions of the analysis. The observed differences between species in microhabitat configuration are consistent with both the composition by forest type of each species sample and the literature information for each species. Microhabitat segregation among these species is discussed with reference to recent theories of habitat selection, ecological specialization and resource partitioning in equilibrium faunas.
sábado, 12 de janeiro de 2013
A new study method of microhabitat structure of small mammals
CERQUEIRA, R.; FREITAS, S.R. 1999. A new study method of microhabitat structure of small mammals. Revista Brasileira de Biologia 59(2):219-223.
Abstract. The variables in habitat studies are usually transformed in such a way that they become abstractions and intuition is lost. We tested a new method for the analysis of habitat using data collected in a grid laid at the “restinga de Maricá”, in Rio de Janeiro State, Brazil. Thirty-seven microhabitat variables were measured at each trap station. We assume that these variables characterize the microhabitat structure at the moment when measurements were taken. The data are transformed in 3 ways: (1) the averages of the measured variables were calculated, as usual in habitat studies; (2) the data are transformed in densities per area in square meters without reduction in the number of variables; and (3) we calculated the natural logarithms of the data thus transformed. The 3 sets were analised through discriminant analysis. The logarithms of densities were the most efficient kind of transformation. This transformation resulted in a significance of p = 0.0001 with 39.72% of variance in the 1st discriminant function and of p = 0.0426 with 31.45% of variance in the 2nd function, and 84.62% of groups correctly classified. We obtained better classification results than previous similar works and we kept the intuition through the data analysis.
Abstract. The variables in habitat studies are usually transformed in such a way that they become abstractions and intuition is lost. We tested a new method for the analysis of habitat using data collected in a grid laid at the “restinga de Maricá”, in Rio de Janeiro State, Brazil. Thirty-seven microhabitat variables were measured at each trap station. We assume that these variables characterize the microhabitat structure at the moment when measurements were taken. The data are transformed in 3 ways: (1) the averages of the measured variables were calculated, as usual in habitat studies; (2) the data are transformed in densities per area in square meters without reduction in the number of variables; and (3) we calculated the natural logarithms of the data thus transformed. The 3 sets were analised through discriminant analysis. The logarithms of densities were the most efficient kind of transformation. This transformation resulted in a significance of p = 0.0001 with 39.72% of variance in the 1st discriminant function and of p = 0.0426 with 31.45% of variance in the 2nd function, and 84.62% of groups correctly classified. We obtained better classification results than previous similar works and we kept the intuition through the data analysis.
sábado, 5 de janeiro de 2013
Predicting presence and abundance of a small mammal species: the effect of scale and resolution
ORROCK, J.L.; PAGELS, J.F.; MCSHEA, W.J.; HARPER, E.K. 2000. Predicting presence and abundance of a small mammal species: the effect of scale and resolution. Ecological Applications 10(5):1356-1366.
Abstract. Management of small mammal communities in forest ecosystems requires a working knowledge of the scales at which species presence and abundance can best be predicted. Habitat-based models were developed to characterize the distribution of a boreal relict, the southern red-backed vole, Clethrionomys gapperi, in the southern Appalachian Mountains, USA, at three hierarchical scales of analysis. Vole presence and abundance were most evident at the high-resolution (macrohabitat) scale, followed by the intermediateresolution scale. The low-resolution model was the least effective for predicting presence or abundance and reflects the need for more resolute landscape classification systems if small mammal populations are to be accounted for in an ecologically relevant manner. Tree and shrub communities indicative of suitable vole habitat included Fraxinus pennsylvanica and Tsuga canadensis in the canopy and Carpinus caroliniana in the understory. Vole abundance increased with incidence of tree species such as Betula alleghaniensis, Pinus rigida, and Prunus serotina in the canopy, and Acer spicatum and woody vines in the understory. Voles were associated with northwest-facing high-elevation sites with abundant rocky substrate, likely a reflection of physiological water and thermal requirements, biogeographic influences, and the importance of substrate complexity for decreasing inter- and intraspecific interactions and avoidance of predators.
Identification of the most effective resolution of landscape characterization improves habitat-based models of C. gapperi population dynamics in managed landscapes. Lowresolution habitat classifications may suffice for detecting suitable vole habitats within forest types, but prediction of vole abundance is most accurate at the greatest resolution, i.e., the macrohabitat scale. The utility of forest communities and habitats at various scales to predict vole presence and abundance suggests that C. gapperi may be a useful indicator species for identification and assessment of habitat important for rare small mammal species in the southern Appalachians.
Abstract. Management of small mammal communities in forest ecosystems requires a working knowledge of the scales at which species presence and abundance can best be predicted. Habitat-based models were developed to characterize the distribution of a boreal relict, the southern red-backed vole, Clethrionomys gapperi, in the southern Appalachian Mountains, USA, at three hierarchical scales of analysis. Vole presence and abundance were most evident at the high-resolution (macrohabitat) scale, followed by the intermediateresolution scale. The low-resolution model was the least effective for predicting presence or abundance and reflects the need for more resolute landscape classification systems if small mammal populations are to be accounted for in an ecologically relevant manner. Tree and shrub communities indicative of suitable vole habitat included Fraxinus pennsylvanica and Tsuga canadensis in the canopy and Carpinus caroliniana in the understory. Vole abundance increased with incidence of tree species such as Betula alleghaniensis, Pinus rigida, and Prunus serotina in the canopy, and Acer spicatum and woody vines in the understory. Voles were associated with northwest-facing high-elevation sites with abundant rocky substrate, likely a reflection of physiological water and thermal requirements, biogeographic influences, and the importance of substrate complexity for decreasing inter- and intraspecific interactions and avoidance of predators.
Identification of the most effective resolution of landscape characterization improves habitat-based models of C. gapperi population dynamics in managed landscapes. Lowresolution habitat classifications may suffice for detecting suitable vole habitats within forest types, but prediction of vole abundance is most accurate at the greatest resolution, i.e., the macrohabitat scale. The utility of forest communities and habitats at various scales to predict vole presence and abundance suggests that C. gapperi may be a useful indicator species for identification and assessment of habitat important for rare small mammal species in the southern Appalachians.
sábado, 29 de setembro de 2012
Toward an ecological synthesis: a case for habitat selection
MORRIS, D.W. 2003. Toward an ecological synthesis: a case for habitat selection. Oecologia 136:1-13.
Abstract. Habitat selection, and its associated density and frequency-dependent evolution, has a profound influence on such vital phenomena as population regulation, species interactions, the assembly of ecological communities, and the origin and maintenance of biodiversity. Different strategies of habitat selection, and their importance in ecology and evolution, can often be revealed simply by plots of density in adjacent habitats. For individual species, the strategies are closely intertwined with mechanisms of population regulation, and with the persistence of populations through time. For interacting species, strategies of habitat selection are not only responsible for species coexistence, but provide one of the most convenient mechanisms for measuring competition, and the various community structures caused by competitive interactions. Other kinds of interactions, such as those between predators and prey, demonstrate that an understanding of the coevolution of habitat-selection strategies among strongly interacting species is essential to properly interpret their spatial and temporal dynamics. At the evolutionary scale, the frequency dependence associated with habitat selection may often allow populations to diverge and diversify into separate species. Habitat selection thereby demonstrates how we can map microevolutionary strategies in behavior onto their population and community consequences, and from there, onto macroevolutionary patterns of speciation and adaptive radiation. We can anticipate that future studies of habitat selection will not only help us complete those maps, but that they will also continue to enrich the panoply of ideas that shape evolutionary ecology.
Abstract. Habitat selection, and its associated density and frequency-dependent evolution, has a profound influence on such vital phenomena as population regulation, species interactions, the assembly of ecological communities, and the origin and maintenance of biodiversity. Different strategies of habitat selection, and their importance in ecology and evolution, can often be revealed simply by plots of density in adjacent habitats. For individual species, the strategies are closely intertwined with mechanisms of population regulation, and with the persistence of populations through time. For interacting species, strategies of habitat selection are not only responsible for species coexistence, but provide one of the most convenient mechanisms for measuring competition, and the various community structures caused by competitive interactions. Other kinds of interactions, such as those between predators and prey, demonstrate that an understanding of the coevolution of habitat-selection strategies among strongly interacting species is essential to properly interpret their spatial and temporal dynamics. At the evolutionary scale, the frequency dependence associated with habitat selection may often allow populations to diverge and diversify into separate species. Habitat selection thereby demonstrates how we can map microevolutionary strategies in behavior onto their population and community consequences, and from there, onto macroevolutionary patterns of speciation and adaptive radiation. We can anticipate that future studies of habitat selection will not only help us complete those maps, but that they will also continue to enrich the panoply of ideas that shape evolutionary ecology.
sábado, 1 de setembro de 2012
Small mammal community structure and composition in the Cerrado Province of central Brazil
MARES, M.A.; ERNEST, K.A.; GETTINGER, D.D. 1986. Small mammal community structure and composition in the Cerrado Province of central Brazil. Journal of Tropical Ecology 2:289-300.
Abstract. Community structure, microhabitat selection, and patterns of species co-occurrence were examined during a 14-month study of small mammals in the Cerrado Province of central Brazil. Data were collected from mark-recapture grids in brejo and gallery forest, and from live-trapping and specimen collection in all habitat types withing cerrado (campo limpo, campo sujo, cerrado [s.s.], cerradão, brejo, valley-side wet campo, and gallery forest). Gallery forest supported the highest species richness, most complex vertical distribution of species, highest level of trophic diversity, and highest macroniche diversity. Degree of habitat selection varied widely. All habitat types supported both rodents and marsupials, althought marsupials tended to be much less common in the grasslands (campos) than in woodlands (cerrado) and forest (cerradão, gallery forest). Some species, such as Didelphis albiventris, occurred in all habitat types, while others were much more restricted. Oryzomys bicolor, for example, ocurred only in gallery forest. No habitat type has a completely distinct fauna: overlap in species composition always occurred with at least one other habitat type. Because of the great variability of habitats, and the fact that subsets of the mammal fauna were frequently habitat specific, the overall species richness of any portion of mixed cerrado vegetation is remarkably high.
Abstract. Community structure, microhabitat selection, and patterns of species co-occurrence were examined during a 14-month study of small mammals in the Cerrado Province of central Brazil. Data were collected from mark-recapture grids in brejo and gallery forest, and from live-trapping and specimen collection in all habitat types withing cerrado (campo limpo, campo sujo, cerrado [s.s.], cerradão, brejo, valley-side wet campo, and gallery forest). Gallery forest supported the highest species richness, most complex vertical distribution of species, highest level of trophic diversity, and highest macroniche diversity. Degree of habitat selection varied widely. All habitat types supported both rodents and marsupials, althought marsupials tended to be much less common in the grasslands (campos) than in woodlands (cerrado) and forest (cerradão, gallery forest). Some species, such as Didelphis albiventris, occurred in all habitat types, while others were much more restricted. Oryzomys bicolor, for example, ocurred only in gallery forest. No habitat type has a completely distinct fauna: overlap in species composition always occurred with at least one other habitat type. Because of the great variability of habitats, and the fact that subsets of the mammal fauna were frequently habitat specific, the overall species richness of any portion of mixed cerrado vegetation is remarkably high.
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