ABREU, M.S.L.; SCHMITZ, G.W.; OLIVEIRA, L.R. 2015. Recursos alimentares nos estratos verticais e sua relação com pequenos mamíferos em uma Floresta de Araucária do sul do Brasil. Revista de Ciências Ambientais 9(2):131-144. doi: 10.18316/1981-8858.16
Abstract. Food resources on the vertical strata and their relationship with small mammals in an Araucaria forest of southern Brazil. This study presents the relationship between the use of different layers by non-volant small mammals and the food resources availability in an Araucaria Forest area from southern Brazil. In this sense, 150 live traps were placed on the ground, understory and canopy. The availability of resources in the layers was evaluated by counting fruits, seeds and captured invertebrates. As a result, 10 species were recorded of non-volant small mammals. An inverse relationship was found between captures of: Akodon montensis and availability of fruits and seeds on the ground (R = -0.95, P = 0.05); Juliomys sp. and invertebrates abundance in the canopy (R = -0.96, P = 0.04); and Gracilinanus microtarsus and total food availability in the canopy (R = -0.99, P = 0.008). The results suggest that in times of food scarcity, small mammals in the Araucaria Forest may need more time searching for food, increasing catch rates in the strata where they live.
terça-feira, 22 de dezembro de 2015
segunda-feira, 21 de dezembro de 2015
Afugentamento, Resgate, Monitoramento e Destinação da Fauna para Consultoria e Licenciamento Ambiental
Curso de Afugentamento, Resgate, Monitoramento e Destinação da Fauna para Consultoria e Licenciamento Ambiental, ministrado por Selvagem em Foco Cursos e Consultoria Ambiental.
Dias: 26, 27 e 28 de Fevereiro de 2016.
Local: Reserva Ecológica de Guapiaçu - RJ
Valor do curso com 10% de desconto até dia 24/12 ou em até 12x sem juros.
Informações: selvagememfoco.com ou selvagememfoco@gmail.com
Dias: 26, 27 e 28 de Fevereiro de 2016.
Local: Reserva Ecológica de Guapiaçu - RJ
Valor do curso com 10% de desconto até dia 24/12 ou em até 12x sem juros.
Informações: selvagememfoco.com ou selvagememfoco@gmail.com
quarta-feira, 14 de outubro de 2015
sábado, 3 de outubro de 2015
Seed survival and dispersal of an endemic Atlantic forest palm: the combined effects of defaunation and forest fragmentation
GALETTI, M. DONATTI, C.I.; PIRES, A.S.; GUIMARÃES JR., P.R.; JORDANO, P. 2006. Seed survival and dispersal of an endemic Atlantic forest palm: the combined effects of defaunation and forest fragmentation. Botanical Journal of the Linnean Society 151:141-149.
Abstract. About 45 palm species occur in the Atlantic forest of Brazil, and most of them are affected by loss of seed dispersers resulting from forest fragmentation and hunting. Here we report the effects of habitat loss and defaunation on the seed dispersal system of an endemic palm, Astrocaryum aculeatissimum. We evaluated seed removal, insect and rodent seed predation, and scatter-hoarding in nine sites, ranging from 19 ha to 79 000 ha. We report the seedling, juvenile and adult palm densities in this range of sites. Endocarps remaining beneath the parent palm had a higher probability of being preyed upon by insects in small, mostly fragmented and more defaunated sites. The frequency of successful seed removal, scatter-hoarding and consumption by rodents increased in the larger, less defaunated sites. Successful removal and dispersal collapsed in small (< 1000 ha), highly defaunated sites and frequently resulted in low densities of both seedlings and juveniles. Our results indicate that a large fraction of Atlantic forest palms that rely on scatter-hoarding rodents may become regionally extinct due to forest fragmentation and defaunation. Current management practices including palm extraction and hunting pressure have a lasting effect on Atlantic forest palm regeneration by severely limiting successful recruitment of prereproductive individuals.
Abstract. About 45 palm species occur in the Atlantic forest of Brazil, and most of them are affected by loss of seed dispersers resulting from forest fragmentation and hunting. Here we report the effects of habitat loss and defaunation on the seed dispersal system of an endemic palm, Astrocaryum aculeatissimum. We evaluated seed removal, insect and rodent seed predation, and scatter-hoarding in nine sites, ranging from 19 ha to 79 000 ha. We report the seedling, juvenile and adult palm densities in this range of sites. Endocarps remaining beneath the parent palm had a higher probability of being preyed upon by insects in small, mostly fragmented and more defaunated sites. The frequency of successful seed removal, scatter-hoarding and consumption by rodents increased in the larger, less defaunated sites. Successful removal and dispersal collapsed in small (< 1000 ha), highly defaunated sites and frequently resulted in low densities of both seedlings and juveniles. Our results indicate that a large fraction of Atlantic forest palms that rely on scatter-hoarding rodents may become regionally extinct due to forest fragmentation and defaunation. Current management practices including palm extraction and hunting pressure have a lasting effect on Atlantic forest palm regeneration by severely limiting successful recruitment of prereproductive individuals.
sábado, 26 de setembro de 2015
Seed predation by rodents and safe sites for large-seeded trees in a fragment of the Brazilian Atlantic forest
PINTO, S.R.R.; SANTOS, A.M.M.; TABARELLI, M. 2009. Seed predation by rodents and safe sites for large-seeded trees in a fragment of the Brazilian Atlantic forest. Brazilian Journal of Biology 69(3):763-771.
Abstract. Seed predation by small rodents is an emerging theme in the ecology of modified landscapes. Here we investigate the role played by the small rodent Oryzomys oniscus as a seed predator of large-seeded trees in a large remnant of the Atlantic forest - the Coimbra forest (3,500 ha), Alagoas state, northeastern Brazil. O. oniscus was captured and identified by setting twenty 500 m long transects, each one composed of 25 traps 20 m apart. This procedure resulted in 483 trap-nights set during a 20-mo period. We used 692 seeds (>15 mm length) from ten local large-seeded tree species for the seed predation trials that basically consisted of three treatments: one seed on the ground freely accessed by vertebrates (unprotected seed), one seed totally protected by an exclosure, and one partially-protected seed (exclosure just for medium-sized and large vertebrates). O. oniscus was captured throughout the Coimbra forest including forest edges (76 captures) and interior areas (67), and this small rodent was responsible for all seed predation visually documented inside exclosures. A 24 hours period of seed exposition permitted elevated rates of seed removal and predation. Seeds were much more removed/predated beneath fruiting trees, but rates varied according to the level of seed protection — 26.3% of predation among partially-protected versus 19.2% among unprotected seeds. Seeds suffered higher levels of seed predation/removal at the forest edge as well (up to 90%). In both habitats, most seeds (>84%) remained intact beneath trees without fruits, regardless of the level of seed protection. Our results suggest that O. oniscus may operate as an effective large-seed predator in forest fragments, in which adult trees without fruits constitute low resource spots and thereby provide, at least temporarily, safe sites for large seeds.
Abstract. Seed predation by small rodents is an emerging theme in the ecology of modified landscapes. Here we investigate the role played by the small rodent Oryzomys oniscus as a seed predator of large-seeded trees in a large remnant of the Atlantic forest - the Coimbra forest (3,500 ha), Alagoas state, northeastern Brazil. O. oniscus was captured and identified by setting twenty 500 m long transects, each one composed of 25 traps 20 m apart. This procedure resulted in 483 trap-nights set during a 20-mo period. We used 692 seeds (>15 mm length) from ten local large-seeded tree species for the seed predation trials that basically consisted of three treatments: one seed on the ground freely accessed by vertebrates (unprotected seed), one seed totally protected by an exclosure, and one partially-protected seed (exclosure just for medium-sized and large vertebrates). O. oniscus was captured throughout the Coimbra forest including forest edges (76 captures) and interior areas (67), and this small rodent was responsible for all seed predation visually documented inside exclosures. A 24 hours period of seed exposition permitted elevated rates of seed removal and predation. Seeds were much more removed/predated beneath fruiting trees, but rates varied according to the level of seed protection — 26.3% of predation among partially-protected versus 19.2% among unprotected seeds. Seeds suffered higher levels of seed predation/removal at the forest edge as well (up to 90%). In both habitats, most seeds (>84%) remained intact beneath trees without fruits, regardless of the level of seed protection. Our results suggest that O. oniscus may operate as an effective large-seed predator in forest fragments, in which adult trees without fruits constitute low resource spots and thereby provide, at least temporarily, safe sites for large seeds.
sábado, 29 de agosto de 2015
Amazonian freshwater habitats experiencing environmental and socieconomic threats affecting subsistence fisheries
ALHO, C.J.R.; REIS, R.E.; AQUINO, P.P.U. 2015. Amazonian freshwater habitats experiencing environmental and socieconomic threats affecting subsistence fisheries. AMBIO 44(5):412-425. doi: 10.1007/s13280-014-0610-z
Abstract. Matching the trend seen among the major large rivers of the globe, the Amazon River and its tributaries are facing aquatic ecosystem disruption that is affecting freshwater habitats and their associated biodiversity, including trends for decline in fishery resources. The Amazon’s aquatic ecosystems, linked natural resources, and human communities that depend on them are increasingly at risk from a number of identified threats, including expansion of agriculture; cattle pastures; infrastructure such as hydroelectric dams, logging, mining; and overfishing. The forest, which regulates the hydrological pulse, guaranteeing the distribution of rainfall and stabilizing seasonal flooding, has been affected by deforestation. Flooding dynamics of the Amazon Rivers are a major factor in regulating the intensity and timing of aquatic organisms. This study’s objective was to identify threats to the integrity of freshwater ecosystems, and to seek instruments for conservation and sustainable use, taking principally fish diversity and fisheries as factors for analysis.
Abstract. Matching the trend seen among the major large rivers of the globe, the Amazon River and its tributaries are facing aquatic ecosystem disruption that is affecting freshwater habitats and their associated biodiversity, including trends for decline in fishery resources. The Amazon’s aquatic ecosystems, linked natural resources, and human communities that depend on them are increasingly at risk from a number of identified threats, including expansion of agriculture; cattle pastures; infrastructure such as hydroelectric dams, logging, mining; and overfishing. The forest, which regulates the hydrological pulse, guaranteeing the distribution of rainfall and stabilizing seasonal flooding, has been affected by deforestation. Flooding dynamics of the Amazon Rivers are a major factor in regulating the intensity and timing of aquatic organisms. This study’s objective was to identify threats to the integrity of freshwater ecosystems, and to seek instruments for conservation and sustainable use, taking principally fish diversity and fisheries as factors for analysis.
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