PIRES, A.S.; LIRA, P.K.; FERNANDEZ, F.A.S.; SCHITTINI, G.M.; OLIVEIRA, L.C. 2002. Frequency of movements of small mammals among Atlantic Coastal Forest fragments in Brazil. Biological Conservation 108:229-237.
Abstract. Rates of interfragment movements were estimated for small mammals inhabiting a group of eight Atlantic Coastal Forest fragments, surrounded by grassland matrix, in order to understand the degree to which each species' population was isolated. Didelphis aurita showed the greatest movement rate (19.4% of recaptures showing interfragment movements), followed by Metachirus nudicaudatus (10.0%), Philander frenata (7.5%), Nectomys squamipes (3.6%), Micoureus demerarae (1.2%) and Akodon cursor (0.25%). Interfragment movements were not detected for Caluromys philander, Oecomys concolor and Oligoryzomys nigripes. Species can be placed along a continuum which goes from species that are represented by a single population in the whole study area, through those with metapopulations, to species that have isolated populations in each fragment. Ability to move among fragments was not related to abundance in the matrix; nevertheless, such ability helps to explain the persistence of species in fragments otherwise too small to support viable populations.
sábado, 25 de agosto de 2012
sábado, 18 de agosto de 2012
Ecology of a small mammal community in an Atlantic forest area in southeastern Brazil
BERGALLO, H.G. 1994. Ecology of a small mammal community in an Atlantic forest area in southeastern Brazil. Studies on Neotropical Fauna and Environment 29(4):197-217.
Abstract. During a 14 month mark-and-release project in a Atlantic forest area (Jurélia Ecological Station), I studied the population ecology of 8 species of small mammals (3 marsupials and 5 rodents). In a 4,307 trap nights, 182 individuals were captured 650 times. The rodents were caught 73% of the total capture and the marsupials 27%. Oryzomys nitidus was the commonest species in the grid followed by Proechimys iheringi and Metachirus nudicaudatus. The marsupials showed a seasonal pattern of reproduction. As a consequence, the population densities has a peak during the wet months with the antrance of the youngs . The rodents, P. iheringi and O. nitidus bred throughtout the year, althought the former one has a peak in the dry months. Density of O. nitidus was fairly constant, whereas that of P. ihenrigi was higher during the recruitment time. Rodents and marsupials contributed with the same biomass in Juréia small mammal community.
Abstract. During a 14 month mark-and-release project in a Atlantic forest area (Jurélia Ecological Station), I studied the population ecology of 8 species of small mammals (3 marsupials and 5 rodents). In a 4,307 trap nights, 182 individuals were captured 650 times. The rodents were caught 73% of the total capture and the marsupials 27%. Oryzomys nitidus was the commonest species in the grid followed by Proechimys iheringi and Metachirus nudicaudatus. The marsupials showed a seasonal pattern of reproduction. As a consequence, the population densities has a peak during the wet months with the antrance of the youngs . The rodents, P. iheringi and O. nitidus bred throughtout the year, althought the former one has a peak in the dry months. Density of O. nitidus was fairly constant, whereas that of P. ihenrigi was higher during the recruitment time. Rodents and marsupials contributed with the same biomass in Juréia small mammal community.
sábado, 11 de agosto de 2012
Elevational gradients in diversity of small mammals
MCCAIN, C.M. 2005. Elevational gradients in diversity of small mammals. Ecology 86(2):366-372.
Abstract. A global analysis of elevational diversity trends for nonvolant small mammals revealed a clear pattern of mid-elevational peaks in species richness. Fifty-six data sets were used to test the predictions of a null model (the mid-domain effect) and climatic hypotheses. Very few data sets fit entirely within the predictions of the null model, and the average predictive power of the null model was low. Regional (gamma) diversity fit the null model better than did local (alpha) diversity. Diversity peaked at higher elevations on taller mountains, consistent with climatic factors producing elevationally correlated habitat bands (Massenerhebung effect). This positive, linear relationship was documented for all data sets but was particularly pronounced for alpha diversity. Gamma diversity, which is generally highly influenced by area, exhibited a trend of highest diversity shifting toward lower elevations, and higher elevational peaks in species diversity at higher latitudes. The elevation of temperate diversity peaks exhibited a negative association with latitude. These results are evidence for the importance of a suite of interacting climatic, area, and geometric factors on elevational diversity patterns, apparent in spite of noise associated with different sampling techniques, localities, and historical pressures.
Abstract. A global analysis of elevational diversity trends for nonvolant small mammals revealed a clear pattern of mid-elevational peaks in species richness. Fifty-six data sets were used to test the predictions of a null model (the mid-domain effect) and climatic hypotheses. Very few data sets fit entirely within the predictions of the null model, and the average predictive power of the null model was low. Regional (gamma) diversity fit the null model better than did local (alpha) diversity. Diversity peaked at higher elevations on taller mountains, consistent with climatic factors producing elevationally correlated habitat bands (Massenerhebung effect). This positive, linear relationship was documented for all data sets but was particularly pronounced for alpha diversity. Gamma diversity, which is generally highly influenced by area, exhibited a trend of highest diversity shifting toward lower elevations, and higher elevational peaks in species diversity at higher latitudes. The elevation of temperate diversity peaks exhibited a negative association with latitude. These results are evidence for the importance of a suite of interacting climatic, area, and geometric factors on elevational diversity patterns, apparent in spite of noise associated with different sampling techniques, localities, and historical pressures.
quinta-feira, 9 de agosto de 2012
Curso: Biologia, ecologia e conservação do boto-da-tainha (Tursiops truncatus)
Estão abertas as inscrições para o I Curso Teórico-Prático de Biologia, Ecologia e Conservação do Boto-da-Tainha (Tursiops truncatus), a se realizar nos dias 25 e 26 de agosto de 2012 na praia de Garopaba, Santa Catarina. Inscrições pelo e-mail institutobaleiafranca@gmail.com ou pelos telefones (48) 9963.1122 e (48) 9682.5718.
sábado, 4 de agosto de 2012
Microtus population biology: demographic changes in fluctuating populations of M. ochrogaster and M. pennsylvanicus in southern Indiana
KREBS, C.J.; KELLER, B.L.; TAMATIN, R.H. 1969. Microtus population biology: demographic changes in fluctuating populations of M. ochrogaster and M. pennsylvanicus in southern Indiana. Ecology 50(4):587-607.
Abstract. Microtus pennsylvanicus and M. ochrogaster are sympatric in southern Indiana grasslands. From June 1965 to August 1967 four populations were live trapped, three of them in 0.8-hectare (2-acre) outdoor pens. Both species increased during 1965 and reached peak densities in summer 1966. Microtus ochrogaster declined abruptly that fall and remained low; M. pennsylanicus declined the following spring.
One of the fenced populations increased to a density about three times that of its unfenced control. By early fall 1966 it had nearly destroyed its food resources and then suffered a severe decline associated with obvious overgrazing and starvation. No such overgrazing has been seen on any unfenced grasslands in this area. Dispersal is probably necessary for normal population regulation in these voles, since fenced populations seem unable to regulate their density below the limit set by starvation.
Both species bred extensively in the winter of 1965-66 during the phase of population increase. There was little or no breeding during the winter after the peak.
Survival of females in the trappable population of both species was high and relatively constant until the end of the cycle. In males, periods of low survival punctuated the increase and peak phases, and these periods of low male survival did not occur at the same time in the two Microtus species. Some mortality processes are thus higly specific for sex and species. In the fenced populations survival rates were very high and no sporadic male losses occurred.
Increasing and peak populations of M. pennsylvanicus and M. ochrogaster are characterized by adults of large body size. During the increase and peak phases some voles stopped growing at low weights (30-40 g) while others reached high aymptotic weights (45-55 g).
The demography of these Microtus species in southern Indiana is similar to that of other cyclic voles and lemmings in temperate and arctic areas.
Abstract. Microtus pennsylvanicus and M. ochrogaster are sympatric in southern Indiana grasslands. From June 1965 to August 1967 four populations were live trapped, three of them in 0.8-hectare (2-acre) outdoor pens. Both species increased during 1965 and reached peak densities in summer 1966. Microtus ochrogaster declined abruptly that fall and remained low; M. pennsylanicus declined the following spring.
One of the fenced populations increased to a density about three times that of its unfenced control. By early fall 1966 it had nearly destroyed its food resources and then suffered a severe decline associated with obvious overgrazing and starvation. No such overgrazing has been seen on any unfenced grasslands in this area. Dispersal is probably necessary for normal population regulation in these voles, since fenced populations seem unable to regulate their density below the limit set by starvation.
Both species bred extensively in the winter of 1965-66 during the phase of population increase. There was little or no breeding during the winter after the peak.
Survival of females in the trappable population of both species was high and relatively constant until the end of the cycle. In males, periods of low survival punctuated the increase and peak phases, and these periods of low male survival did not occur at the same time in the two Microtus species. Some mortality processes are thus higly specific for sex and species. In the fenced populations survival rates were very high and no sporadic male losses occurred.
Increasing and peak populations of M. pennsylvanicus and M. ochrogaster are characterized by adults of large body size. During the increase and peak phases some voles stopped growing at low weights (30-40 g) while others reached high aymptotic weights (45-55 g).
The demography of these Microtus species in southern Indiana is similar to that of other cyclic voles and lemmings in temperate and arctic areas.
quarta-feira, 1 de agosto de 2012
Mamíferos: da Terra aos Mares
A equipe do Laboratório de Ecologia de Mamíferos da Unisinos têm o prazer de convidar todos a participar da oficina Mamíferos: da Terra aos Mares.
A oficina visa apresentar o grupo dos mamíferos com aspectos de sua evolução, diversidade, ecologia, manejo, conservação e relações com o homem. A oficina ocorrerá nos dias 24 e 25 de agosto, e 1º de setembro de 2012, na Unisinos (Univerdade do Vale do Rio dos Sinos), em São Leopoldo, RS. As inscrições podem ser realizadas diretamente pela internet através do link: http://www.unisinos.br/extensao/eventos/EX120309/EX120309-00001/620/apresentacao.
DATAS: 24 e 25 de agosto, e 1º de setembro de 2012.
INVESTIMENTO: R$ 100,00.
INFORMAÇÕES: www.unisinos.br/eventos (eventos saúde).
CONTEÚDO PROGRAMÁTICO PREVISTO
A oficina será dividida em quatro módulos, sendo o primeiro módulo uma apresentação geral sobre características, diversidade e evolução dos mamíferos. Os quatro módulos seguintes apresentarão aspectos gerais e ecológicos sobre os mamíferos terrestres, e os quatro módulos seguintes apresentarão técnicas de estudo e monitoramento de populações de mamíferos marinhos, bem como suas interações com o homem.
O conteúdo detalhado previsto (sujeito a modificações) segue abaixo:
24/ago/2012
- Introdução geral: mamíferos, da terra aos mares (Msc Paulo T. Sarti, Fernando R.V. Lopes).
A oficina visa apresentar o grupo dos mamíferos com aspectos de sua evolução, diversidade, ecologia, manejo, conservação e relações com o homem. A oficina ocorrerá nos dias 24 e 25 de agosto, e 1º de setembro de 2012, na Unisinos (Univerdade do Vale do Rio dos Sinos), em São Leopoldo, RS. As inscrições podem ser realizadas diretamente pela internet através do link: http://www.unisinos.br/extensao/eventos/EX120309/EX120309-00001/620/apresentacao.
DATAS: 24 e 25 de agosto, e 1º de setembro de 2012.
INVESTIMENTO: R$ 100,00.
INFORMAÇÕES: www.unisinos.br/eventos (eventos saúde).
CONTEÚDO PROGRAMÁTICO PREVISTO
A oficina será dividida em quatro módulos, sendo o primeiro módulo uma apresentação geral sobre características, diversidade e evolução dos mamíferos. Os quatro módulos seguintes apresentarão aspectos gerais e ecológicos sobre os mamíferos terrestres, e os quatro módulos seguintes apresentarão técnicas de estudo e monitoramento de populações de mamíferos marinhos, bem como suas interações com o homem.
O conteúdo detalhado previsto (sujeito a modificações) segue abaixo:
24/ago/2012
- Introdução geral: mamíferos, da terra aos mares (Msc Paulo T. Sarti, Fernando R.V. Lopes).
25/ago/2012
- Biologia e ecologia de pequenos mamíferos (Msc Maury S.L. Abreu).
- Padrões de microestrutura de pelos: identificando mamíferos (Nathalia S. Freitas).
- Mamíferos terrestres de médio e grande porte (Msc Paulo T. Sarti).
- O uso do habitat por mamíferos terrestres (Guilherme W. Schmitz).
01/set/2012
- Técnicas de estudo em mamíferos-marinhos: coleta, curadoria de coleção e estudos osteológicos (Biol. Ana Paula Costa).
- Técnicas de estudo em mamíferos-marinhos: monitoramento de populações (Biol. Rodrigo Machado, Biol. Ana Paula Costa, Fernando R.V. Lopes).
- Interações entre mamíferos aquáticos e a atividade pesqueira: da pesca cooperativa ao conflito (Biol. Rodrigo Machado).
- Dimensões humanas (Mônica Terra, Biol. Ana Carolina Pont).
Assinar:
Postagens (Atom)