Bat inventory in a Caatinga area in Northeastern Brazil, with a new occurrence in the state of Paraíba

BELTRÃO, M.G.; ZEPPELINI, C.G.; FRACASSO, M.P.A.; LOPES, L.C.S. 2015. Bat inventory in a Caatinga area in Northeastern Brazil, with a new occurrence in the state of Paraíba. Neotropical Biology and Conservation 10(1):15-20. doi: 10.4013/nbc.2015.101.06

Abstract. The Caatinga is a semi-arid ecosystem with a long history of anthropic impacts and scientific negligence. Since bats are the second most diverse group of mammals and have wide ecological roles, a well-based comprehension of their diversity for an area is important for management and conservationist actions. The goal of this study is to provide a list of the bat species found in Private Reserve of Natural Heritage Fazenda Almas, Paraíba, Northeastern Brazil. By sampling with mist nets and exploring roosts, we captured 126 specimens and recorded 19 species from 5 families. The most abundant species were Artibeus planirostris, Peropteryx macrotis, Myotis nigricans, and Carollia perspicillata. We registered high diversity of Phyllostominae, as well as the occurrence of the genus Histiotus in the state for the first time. Our results indicate that Caatinga areas can maintain bat assemblages with levels of diversity similar to moist tropical areas, which highlights the need to expand the network of protected areas in this threatened ecosystem.

Niche separation between the maned wolf (Chrysocyon brachyurus), the crab-eating fox (Dusicyon thous) and the hoary fox (Dusicyon vetulus) in central Brazil

JÁCOMO, A.T.A.; SILVEIRA, L.; DINIZ-FILHO, J.A.F. 2004. Niche separation between the maned wolf (Chrysocyon brachyurus), the crab-eating fox (Dusicyon thous) and the hoary fox (Dusicyon vetulus) in central Brazil. Journal of Zoology, London 262:99-106. DOI:10.1017/S0952836903004473

Abstract. Four species of canids occur in the Cerrado of central Brazil. Three of them, the maned wolf Chrysocyon brachyurus, the crab-eating fox Dusicyon thous and the hoary fox Dusicyon vetulus, were studied in Emas National Park between 1996 and 1999 to investigate niche separation. The diet of the three species was studied to understand niche breadth and degree of overlap. Habitat and activity patterns were used as second and third ecological parameters to define niche dimensions, and were estimated using camera-trap data. The maned wolf is the largest species, weighing c. 21 kg, and is about three times larger than the crab-eating fox and six times larger than the hoary fox. The major ecological differences between the three species were found in their food niche and habitat use, where crab-eating fox presented higher differences from the hoary fox (Pianka’s index of niche overlap (O) = 0.405). Despite differences in niche breadth, habitat use between the hoary fox and the maned wolf were more similar, explaining their larger overlap, in comparison with habitat use by the crab-eating fox. Activity patterns among the species showed less divergence. The three species presented two activity peaks, one in the dusk–night period and another in the morning period. These data permit a better understanding of the ecological separation of the three Cerrado canids that enables their coexistence.

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.

Short-term fire effects on small mammal populations and vegetation of the Northern Chihuahuan Desert

MONASMITH, T.J.; DEMARAIS, S.; ROOT, J.J.; BRITTON, C.M. 2010. Short-term fire effects on small mammal populations and vegetation of the Northern Chihuahuan Desert. International Journal of Ecology, v. 2010, Article ID 189271, 9 pages. doi: 10.1155/2010/189271.

Abstract. Fire is an important ecological factor in semidesert grass-shrub community dynamics, but there is a lack of designed field experiments documenting effects on vegetation and small mammals.We document effects of June prescribed fire on vegetation and small mammals on 20, 25-ha study areas in the Northern Chihuahuan Desert of Southern New Mexico, USA one month and one year posttreatment. Canopy cover of shrubs and grasses recovered to 68 and 27% of the preburn canopy cover, respectively, after one year. Prescribed burns during June enhanced short-term forb production by reducing competition from grasses and shrubs. Thirty thousand trap-nights yielded 1744 captures of 766 individuals of 15 small mammal species. Burns did not affect small mammal species richness and species diversity. Relative abundance of Merriam’s kangaroo rats (Dipodomys merriami) was 91% greater on burned sites than on control sites one year postburn. Silky pocket mouse (Perognathus flavus) relative abundance was 221% greater on burned sites one year postburn. Chihuahuan Desert pocket mice (Chaetodipus eremicus) responded negatively to the fire, with relative abundance 170% greater on control sites (P = .080). Burning produced short-term benefits for two heteromyids, Merriam’s kangaroo rats and silky pocket mice.

Seasonal activity patterns of rodents in a sagebrush community

O'FARRELL, M.J. 1974. Seasonal activity patterns of rodents in a sagebrush community. Journal of Mammalogy 55(4):809-823.

Abstract. Twelve species of nocturnal rodents were studied on a 2.7-hectare plot of sagebrush desert in west-central Nevada. Six species, Dipodomys merriami, D. ordii, D. panamintinus, D. microps, Onychomys torridus, and Peromyscus maniculatus, were active throughout the year. Four species, Perognathus longimembris, P. formosus, Microdipodops megacephalus, and Reithrodontomys megalotis, hibernated and were active only in spring, summer, and autumn. Onychomys leucogaster and Neotoma lepida were trapped intermittently throughout the year but were not permanente residents on the area. Differences in time of daily activity were found between potential competitors demonstrating a degree of temporal isolation. Time after sunset and amount of moonlight were the two most important factors correlated to rodent activity. Ambient temperature, wind, cloud cover, precipitation, and water vapor pressure had little effect on activity except when extreme conditions prevailed.

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.

Disponibilidade de frutos e a dieta de Lycalopex vetulus (Carnivora - Canidae) em um cerrado de Mato Grosso, Brasil

DALPONTE, J.C.; LIMA, E.S. 1999. Disponibilidade de frutos e a dieta de Lycalopex vetulus (Carnivora - Canidae) em um cerrado de Mato Grosso, Brasil. Revista Brasileira de Botânica 22(2):325-332.

Abstract. (Fruit availability and the diet of Lycalopex vetulus (Carnivora - Canidae) in a cerrado vegetation of Mato Grosso, Brazil). The fruiting phenology of 41 species known as potential food for mammals was monitored monthly during the period of 1985 and 1986, and compared with the frugivorous diet of the hoary fox (Lycalopex vetulus) in a cerrado area near Chapada dos Guimarães National Park, Mato Grosso, Brazil. The fruiting pattern was seasonal, with peaks of greater availability in the beginning of dry and wet seasons. Hancornia speciosa, Rauwolfia sp. and Solanum lycocarpum showed a long (nine to 12 months) fruiting pattern, while Guettarda viburnioides and Mouriri elliptica a short pattern (five to eight months). Seventy percent of the fruit species were eaten by the hoary fox. Despite the large number of fruit species consumed, a small percentage (26%) of these species reaches 10% of the occurrence frequency in the fox scats. The consumption of fruits by the hoary fox was opportunistic, generally consistent with the seasonal fruiting pattern in the study area. H. speciosa and S. lycocarpum were considered the most important fruit species in the diet of the hoary fox, since they give sources of alternative food year round, including periods of low availability of other fruits, like the peak os dry season. Changes in the intensity of fruit used by the hoary fox, like the replacement of some species by others, seem to show states of satiation and interest for new atractive fruits. Apparently, accessibility, strong smell and energetic content are features of the fruits that determine primary preferences for some species. The role of the hoary fox as an important agent to diesperse fruits in the cerrado may be suggested by the large number of fruit species eaten, and by the presence of undamaged seeds in the scats.

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.

Variação espacial e influência do habitat na estrutura de comunidades de pequenos mamíferos em áreas de campo rupestre no Distrito Federal

SANTOS, R.A.L.; HENRIQUES, R.P.B. 2010. Variação espacial e influência do habitat na estrutura de comunidades de pequenos mamíferos em áreas de campo rupestre no Distrito Federal. Biota Neotropica 10(1):31-38.

Abstract. In the present study, we investigated the communities of small mammals in rocky fields in the Federal District. We examined the composition, abundance and richness and their relation to the structure of the habitat and if there is significant spatial variation in species composition among sites of rocky fields. Small mammals were sampled by live-trapping techniques in seven sites. The total effort for the seven sites was 5.680 trap-nights; we captured 157 individuals in eight species of rodents. Calomys tener and Cerradomys scotti were the most abundant species in the study sites, with 47.1 and 18.0% of total individuals, respectively. The results showed that the areas of rocky fields of the Federal District have a fauna of small mammals (average of four, range of variation of three to five species), comparable to other Cerrado physiognomies. The complexity of the habitat proved to be a major determinant in the composition of communities of small mammals in rocky fields. There was a distinction between communities of small mammals of the sites of APA Gama e Cabeça do Veado and the sites of the APA de Cafuringa. There was influence of the distance between the places on the composition of species with decreasing similarity with increasing distance among sites. The differences in environmental conditions, the structure of the habitat and the fact that it was possible two biogeographical regions may explain the faunal differences between the two regions.

The question of scale in threat analysis: a case study with Brazilian mammals

GRELLE, C.E.V.; FONSECA, G.A.B.; FONSECA, M.T.; COSTA, L.P. 1999. The question of scale in threat analysis: a case study with Brazilian mammals. Animal Conservation 2:149-152.

Abstract. Rates of biodiversity loss are clearly associated with a reduction in the extent of original habitat. The most frequently used method to derive such estimates comes from the well-known species–area relationship. We explored the relationship between habitat loss and area for the Brazilian mammal fauna on a biome level (Atlantic Forest, Cerrado and the Brazilian portion of the Amazon basin), as well as on a smaller regional scale (the Rio Doce Valley of the Atlantic Forest). Habitat loss overestimates the number of threatened species when the entire species pool is considered (endemics and wideranging species). Restricting the analyses to the endemic species, the predicted extinction as a function of habitat loss in the Atlantic Forest and in the Cerrado is found to be greater than the number of taxa actually listed as threatened. This relation is reversed in the Amazon. When considering only the localized species pool for the Rio Doce Valley region of the Atlantic Forest, the function accurately predicts the number of extinctions resulting from habitat loss. We suggest that there is both theoretical and empirical evidence to suggest that threat analysis will generate more accurate estimates of species loss when conducted on a more local scale, particularly for the fauna of non-insular, continental regions. Furthermore, other phenomena affecting the likelihood of extinction of certain groups of species, such as hunting, need to be taken into account in order to better understand the dynamics of biodiversity loss.

Coexistence of temporal partitioned spiny mice: roles of habitat structure and foraging behaviour

JONES, M.; MANDELIK, Y.; DAYAN, T. 2001. Coexistence of temporal partitioned spiny mice: roles of habitat structure and foraging behaviour. Ecology 82(8):2164-2176.

Abstract. Two coexisting species of spiny mice in rocky deserts in Israel temporally partition activity in opposite parts of the diel cycle. Acomys cahirinus is nocturnal and A. russatus is diurnal, although it becomes nocturnal if its congener is experimentally removed, suggesting that the temporal partitioning is driven by interspecific competition. Such extreme temporal partitioning within the diel cycle has not previously been recorded elsewhere among mammals. Using artificial food patches, we studied microhabitat use and foraging efficiencies under seasonally variable predator regimes and physiological pressures to assess the roles that habitat structure and foraging behavior might play in coexistence. The two species showed trade-offs in foraging efficiency leading to different strategies of microhabitat use that may help promote coexistence. A. cahirinus is a "cream skimmer," a relatively inefficient forager that gives up at relatively high giving-up densities, and a habitat generalist; whereas A. russatus is a habitat specialist, perhaps compensating for this restricted niche by foraging very efficiently to low giving-up densities. Seasonal shifts in foraging microhabitat suggest that the response to predation risk from snakes in summer overrides and opposes the effects of physiological costs and risk from owls and diurnal raptors, leading to increased predatory risk and foraging microhabitat overlap in summer. Temporal partitioning of the food resource may compensate for decreased partitioning of the habitat resource in summer. Provision of cover was more important than escape distance in determining habitat and microhabitat use. Boulder fields in rocky deserts provide a physical structure that is more complex and provides more continuous cover than is available in open deserts, where most research on community structure of desert rodents has been carried out. We propose that this physical structure of rocky deserts, in conjunction with the desert adaptations of A. russatus, may enable the extreme temporal partitioning to opposite parts of the diel cycle and, therefore, contributes to coexistence in this community.

Effects of fire on the abundance of xenarthrans in Mato Grosso, Brazil

PRADA, M.; MARINHO-FILHO, J. 2004. Effects of fire on the abundance of xenarthrans in Mato Grosso, Brazil. Austral Ecology 29:568-593.

Abstract. Fire is an important ecological factor in Cerrado vegetation of central Brazil, and in other savanna

ecosystems. The effect of fire on the abundance of some Xenarthran mammal species Priodontes maximus

Kerr, 1792 (giant armadillo), Euphractus sexcinctus Linnaeus, 1758 (yellow armadillo) and Myrmecophaga tridactyla Linnaeus, 1758 (giant anteater)) was studied at Reserva Xavante do Rio das Mortes, a 329 000 ha Xavante Indian reserve in the Cerrado of Mato Grosso, Brazil. Track counts were used to compare the abundance of these mammals along seven burned and seven unburned transects, on seven occasions between August 1995 and August 1996. The number of tracks in burned and unburned areas did not differ. Xenarthrans probably use burned areas to obtain food resources, basically termites and ants. Xavante traditional fire hunts may reduce fuel accumulation and function as a mechanism to prevent more destructive fires. Fire management at Reserva Xavante is recommended because the burning system of Brazilian farmers is already influencing the Xavante community. Xavante traditional knowledge about fire could be an important instrument for this management.

Seed removal by small mammals, birds and ants in semi-arid Chile, and comparison with other systems

KELT, D.A.; MESERVE, P.L.; GUTIÉRREZ, J.R. 2004. Seed removal by small mammals, birds and ants in semi-arid Chile, and comparison with other systems. Journal of Biogeography 31:931-942.

Abstract.

Aim. This study aims to evaluate the relative importance of birds, small mammals, and ants as seed predators at a semi-arid site in northern Chile.

Location. Northern Chile, in Parque Nacional Bosque Fray Jorge (30º41' N, 71º40' W, c. 80 m elevation).

Methods. We studied the relative abilities of birds, small mammals, and ants to find and remove millet seeds either singly (i.e. background seed removal) or in bulk. Single seeds were set in shallow depressions in Plexiglas trays which were established in long and arbitrary transects, and were available either to birds (diurnally) or small mammals (nocturnally) or were covered by hardware cloth and therefore available only to ants. Bulk removal was evaluated with seeds in Petri dishes that also were established in long and arbitrary transects, and trays were either open diurnally (birds) or nocturnally (small mammals); a third set of trays was covered with hardware cloth cages to excluded vertebrates, and ants were given access to Petri dishes with twigs that were arranged across the edge of the dishes. All experiments lasted four days and nights, and trays and dishes were checked and replenished as needed in the morning and evening. In the former study vertebrate consumption was determined as the mean number of seeds removed from trays (within a given transect) minus the number removed from ant-only trays. Because ants were rarely seen in vertebrate access Petri dishes, however, we did not correct consumption there. Treatments were compared using repeated measures mixed model analysis of variance. In addition to evaluating patterns within this community, we compared our results against those obtained in similar studies in various arid regions.

Results. Diurnal seed consumption was significantly greater than nocturnal seed consumption, which in turn was significantly greater than consumption by ants. Diurnal consumption was highly seasonal, evidently corresponding to the seasonal arrival and departure of migratory birds. In general, South American sites exhibit much lower levels of seed predation than sites in the northern hemisphere, but removal at our site appears to be much greater and more strongly aviandominated than at other sites in South America. Our results are consistent with predictions based on a hypothesis relating precipitation to seed predictability.

Main conclusions. Both birds and small mammals were much more important seed consumers at our site than elsewhere in South America, whereas ants have been relatively unimportant at all South American sites studied to date. Although the dominant seed consumers differ across sites, overall levels of seed removal

appear similar in South America and Australia, and substantially lower than reported from sites in the northern hemisphere and Africa.