Recursos alimentares nos estratos verticais e sua relação com pequenos mamíferos em uma Floresta de Araucária do sul do Brasil

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.

Mastofauna do Planalto das Araucárias, Rio Grande do Sul, Brasil

MARQUES, R.V.; CADEMARTORI, C.V.; PACHECO, S.M. 2011. Mastofauna do Planalto das Araucárias, Rio Grande do Sul, Brasil. Revista Brasileira de Biociências 9(3):278-288. 

Abstract. Mammals from Araucaria’s Plateau, state of Rio Grande do Sul, Brazil. Wild small (including flying), medium and large mammals long term surveys were carried out in Protected areas in Araucarias Plateau in state of Rio Grande do Sul, Brazil. Studies were done in native pine forests (Araucaria angustifolia), Araucaria plantation, recuperation stage of native vegetation after deforestation and around urban areas. Study methods included the use of Tomahawk traps, pitffal traps, mist nets, camera traps, footprints, direct observations of animals and dead animals in roads. Sixty six species of native mammals and one exotic species (hare – Lepus europaeus) were detected. Araucaria’s Plateau is important for conservation of mammals because has natural environments that support endangered species.

Barn Owl pellets (Aves: Tyto furcata) reveal a higher mammalian richness in the Restinga de Jurubatiba National Park, Southeastern Brazil

LEMOS, H.M.; SILVA, C.A.O.; PATIU, F.M.; GONÇALVES, P.R. 2015. Barn Owl pellets (Aves: Tyto furcata) reveal a higher mammalian richness in the Restinga de Jurubatiba National Park, Southeastern Brazil. Biota Neotropica 15(2):1-9. http://dx.doi.org/10.1590/1676-06032015012114

Abstract. The northern coast of the state of Rio de Janeiro harbors the largest coastal sandy plains (restingas) of southeastern Brazil, severely threatened due to recent human occupation. In this context, mammal inventories becomes urgent to support biodiversity conservation and management policies. This paper aims to update the knowledge on the mammalian species richness of Restinga de Jurubatiba National Park by analyzing pellets of the Barn owl Tyto furcata. The analyses of 4745 mammalian bone fragments (1739 individuals) revealed the occurrence of 17 species belonging to the orders Rodentia (9 spp.), Didelphimorphia (2 spp.) and Chiroptera (6 spp.). The rodents Mus musculus and Cerradomys goytaca accounted for 77.2% of the total individuals preyed, suggesting that the Barn owl hunts in both disturbed and natural open shrub formations. A compilation of previous records, together with those provided in the present study, indicates the occurrence of 44 species of mammals in the Restinga de Jurubatiba National Park, of which six (13.6%) were exclusively detected in pellets. These new records include species adapted to open formations of the interior of Brazil that were not previously reported in restingas on the basis of voucher-specimens, such as the rodents Necromys lasiurus and Calomys tener, the latter being recorded for the first time in the littoral of Rio de Janeiro state. This study underscores the importance of owl pellet analysis as a complementary and indispensable method for inventorying mammals. The results highlight the Restinga de Jurubatiba National Park as one of the restingas in Southeastern Brazil with the highest number of mammal species.

First record of the bushy-tailed opossum, Glironia venusta, Thomas, 1912, (Didelphimorphia) from Manaus, Amazonas, Brazil

CALZADA, J.; DELIBES, M.; KELLER, C.; PALOMARES, F.; MAGNUSSON, W. 2008. First record of the bushy-tailed opossum, Glironia venusta, Thomas, 1912, (Didelphimorphia) from Manaus, Amazonas, Brazil. Acta Amazonica 38(4):807-810.

Abstract. A new record of a very rarely observed mammal, the bushy-tailed opossum, Glironia venusta (Didelphimorphia), was obtained for the Adolpho Ducke Forest Reserve, Manaus, Amazonas state, Brazil. Only 17 other records existed of this species, most from the 1980s. There were only three previous records of the species from Brazil (in the states of Pará, Amazonas and Rondônia). This new record supports the notion that G. venusta is a locally rare species throughout its range, but widely distributed in Brazilian Amazonia.

Tafonomía de restos de micromamíferos recuperados del sitio arqueológico Agua de La Mula (Mendoza, Argentina) y su implicancia en la subsistencia humana

FERNÁNDEZ, F.J.; DE SANTIS, L.J.M. 2013. Tafonomía de restos de micromamíferos recuperados del sitio arqueológico Agua de La Mula (Mendoza, Argentina) y su implicancia en la subsistencia humana. Cuadernos del Instituto Nacional de Antropología y Pensamiento Latinoamericano - Series Especiales 1(1):181-195.

Abstract. Micromammal remains from the archaeological sequence of Agua de La Mula (35º22'24,9''S, 68º15'04,2''W, south-central Mendoza, Argentina) are taphonomically studied. The remains (NISP=1026, MNE=1,026, MNI=491) were recovered from the Late Holocene layers (1,600-1,000 years C14 BP). The micromammal assemblages are composed by 10 taxa of rodents, one chiropteran and two marsupials, associated to transitional mosaic of Patagonian steppe and Monte desert environments. The absence of cut marks and the presence of few burned remains recovered from the site would indicate no human consumption. Moreover, the presence of pellets preserved in stratigraphy and light digestive corrosion on some teeth, indicate that the main accumulator agents were probably avian strigiforms. The absence of weathering, rodent marks, hydraulic transport, root action, and diagenesis, suggest a good preservation and a rapid incorporation of the material in the stratigraphic context. However, trampling, sedimentary corrosion and manganese oxide evidences were seen on the micromammal remains, indicating some episodes of humidity inside the cave. Finally, this information provided here would help us to explain the scope of the resource intensification process, proposed for the region in previous researches. In this sense, possibly this process could not have been so pronounced for that hunter-gatherers exploit the micromammals.

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.

The action of post-dispersal beetles (Coleoptera: Scarabaeidae) and ants (Hymenoptera: Formicidae) on scats of Didelphis spp. (Mammalia: Didelphidae)

CÁCERES, N.C.; MONTEIRO-FILHO, E.L.A. 2006. The action of post-dispersal beetles (Coleoptera: Scarabaeidae) and ants (Hymenoptera: Formicidae) on scats of Didelphis spp. (Mammalia: Didelphidae). Revista de Biología Tropical 54(4):1197-1203.

Abstract. A two year study of dung beetles and ants acting on scats of two species of opossum (Didelphis spp.) was carried out. Scats were left in the field in order to detect post-dispersal agents. A portion of each scat (30%) was examined for seeds in the laboratory. Beetles were recovered from burrows (51% of 84 faecal samples left in the field) where they either buried scats of opossums or were attracted, together with ants, to pitfalls (N= 10) baited with opossum scats. Dung beetles were the main post-dispersal agents of seeds found in scats of opossums, rolling the scats away or burying then on the site of deposition. They buried faeces at 4 to 15 cm in depth (N= 22 tunnels). The main dung beetles identified (medium to large size) were Eurysternus (28.7 % in pitfalls) and Dichotomius (13.7 %), Coprophanaeus (seen only directly on faeces), besides small-bodied beetles (<10 mm; 57.6 %). The ant Acromirmex sp. transported some seeds from scats. This species was present in 25.5% of all Formicidae samples (pitfall). These post-dispersal agents contribute to avert scat seed predators such as rodents, and to accelerate seed bank formation.

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.

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.

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.

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.

A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas) (Mammalia, Didelphidae) in the Atlantic forest of south-eastern Brazil

JUNIOR, E.A.M.; CHIARELLO, A.G. 2005. A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas) (Mammalia, Didelphidae) in the Atlantic forest of south-eastern Brazil. Revista Brasileira de Zoologia 22(1):85-91.

Abstract. From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905) (three males and four females) were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points), and minimum convex polygon (MCP) methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100%) ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95%) were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night) than females (335.1 m/night) (t test, t = 3.609, p = 0.001). We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less). Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817).

Chironectes minimus

MARSHALL, L.G. Chironectes minimus. Mammalian Species 109:1-6.

Abstract. Taxonomy, description, distribution, ecology and behavior of Chironectes minimus, a small neotropical marsupial (Order Didelphimorphia, family Didelphidae, subfamily Didelphinae).

Caluromys lanatus

CÁCERES, N.C.; CARMIGNOTTO, A.P. 2006. Caluromys lanatus. Mammalian Species 803:1-6.

Abstract. Taxonomy, description, distribution, ecology and behavior of Caluromys lanatus, a small neotropical marsupial (Order Didelphimorphia, family Didelphidae, subfamily Caluromyinae).

Anomalous color in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora)

ABREU, M.S.L.; MACHADO, R.; BARBIERI, F.; FREITAS, N.S.; OLIVEIRA, L.R. 2013. Anomalous color in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora). Brazilian Journal of Biology 73(1):185-194.

Abstract. Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males  and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are  becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves  primarily through echolocation, and their refuges provide protection against light and predation. It is possible that  anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported.  Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.

Rediscovery and redescription of Marmosops handleyi (Pine, 1981) (Didelphimorphia: Didelphidae), the least known Andean slender mouse opossum

DÍAZ-N., J.; GÓMEZ-LAVERDE, M.; SÁNCHEZ-GIRALDO, C. 2011. Rediscovery and redescription of Marmosops handleyi (Pine, 1981) (Didelphimorphia: Didelphidae), the least known Andean slender mouse opossum. Mastozoología Neotropical 18(1):45-61.

Abstract. Marmosops handleyi was briefly described in 1981 based on two specimens collected in 1950 in the northern Andes of Colombia. Until now there have been no additional reported records for this species, and knowledge about its taxonomy, ecology, natural history and evolutionary relationships is deficient. Aiming to assess its current distribution, we searched for this species at four localities in the northern part of the Colombian Cordillera Central, where we collected the new material on which this report is based. Morphological comparisons with a sympatric congeneric species herein identified as M. caucae, revealed new external and craniodental characters that we use to redescribe M. handleyi. Our phylogenetic analysis groups M. handleyi as the sister taxon of a clade of small-bodied forms (M. parvidens +  M. pinheiroi), and a basal polytomy includes M. caucae (a Colombian taxon currently synonymized with M. impavidus) and other large-bodied forms. Finally, a reassessment of M. handleyi’s current conservation status suggests that the species should be transferred from Critically Endangered (CR) to Endangered (EN) IUCN category based on our discovery of additional extant populations.

Jumping ability in the arboreal locomotion of didelphid marsupials

DELCIELLOS, A.C.; VIEIRA, M.V. 2009. Jumping ability in the arboreal locomotion of didelphid marsupials. Mastozoología Neotropical 16(2):299-307.

Abstract. Didelphid marsupials are considered to cross discontinuities between arboreal supports using a cautious locomotion, using the prehensile tail as fifth limb. However, this ability was only described for Caluromys philander. We describe and compare the locomotory performance and postural behavior of seven species of didelphid marsupials crossing discontinuities between artificial supports representing arboreal gaps. Individuals were captured in areas of Atlantic Forest in Rio de Janeiro State, Brazil. Animals were stimulated to jump from a fixed horizontal support one meter above the ground to an inclined support of same diameter. We measured the maximum distance of jump (40, 60, 80 or 100 cm) and reach or distance actually reached by the jump. Arboreal species (Marmosops incanus, Gracilinanus microtarsus, Micoureus paraguayanus, and C. philander) jumped longer distances and had longer relative reach in jumps than semi-terrestrial species (Didelphis aurita, and Philander frenatus). Only the specialized terrestrial Metachirus nudicaudatus did not jump in the tests. The relation between absolute reach and body size was weak and non significant. This study did not corroborate the view that didelphid marsupials cross discontinuities between arboreal supports only through a cautious locomotion, without jumping. On the contrary, we identified patterns of jumping performance and behavior of didelphid marsupials related to their use of the vertical strata.

Frugivoria e potencial dispersão de sementes pelo marsupial Gracilinanus agilis (Didelphidae: Didelphimorphia) em áreas de Cerrado no Brasil central

CAMARGO, N.F.; CRUZ, R.M.S.; RIBEIRO, J.F.; VIEIRA, E.M. 2011. Frugivoria e potencial dispersão de sementes pelo marsupial Gracilinanus agilis (Didelphidae: Didelphimorphia) em áreas de Cerrado no Brasil central. Acta Botanica Brasilica 25(3):646-656.

Abstract. (Frugivory and potential seed dispersal by the marsupial Gracilinanus agilis (Didelphidae: Didelphimorphia) in areas of Cerrado in central Brazil). In the present study, we investigated patterns of fruit consumption and viability of seeds consumed by the marsupial Gracilinanus agilis (Burmeister, 1854) in four cerrado sites in central Brazil.  Faecal analysis indicated that this mammal feeds on seeds of pioneer plant species of Melastomataceae (Miconia albicans (Sw.) Triana, M. cuspidata Naudin, M. ferruginata DC., M. pepericarpa DC., M. pohliana Cogn. and Ossaea congestil ora (Naudin) Cogn.), Solanaceae (one unidentified species), and Viscaceae (Phoradendron perrottetii (DC.) Eichler, mistletoe). We recorded the highest reported rate of fruit consumption for Gracilinanus, with about 45% of the scats containing seeds and 86% containing items derived from fruits (N = 422). With the exception of O. congestiflora, the remaining seed species tested did not suffer negative effects on germination rates after passing through the marsupial guts. The analysis of intraspecific variation in the total number of Miconia seeds found in scats indicated that females defecate a significantly greater number of seeds (mean±EP = 21.7±3.8) than males (14.4±3.0) (F = 26.32; P < 0.0001). The factor season was also significant (F=452.22; P<0.0001) as well as the interaction between sex and season (F=30.10; P < 0.0001).  Both females and males increased their fruit consumption in the dry season, but in the rainy season females had more seeds than males in their faeces. Later during this season, we observed a higher number of Miconia seeds defecated by reproductive females (24.7±6.6) compared to non-reproductive females (12.9±2.8) (P = 0.031). Our results indicate that G. agilis feeds selectively on Melastomataceae, which suggests these plants play an important role in the diet of this marsupial in relation to energy and water demands, especially during the dry-cool season.

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.

Frequency of movements of small mammals among Atlantic Coastal Forest fragments in Brazil

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.