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Corumbá, Brazil

Campos Z.,Laboratorio Of Vida Selvagem | Magnusson W.E.,National Institute of Amazonian Research | Marques V.,Instituo Chico Mendes de Conservacao de Biodiversidade
Herpetologica | Year: 2013

We estimated growth rates of Dwarf Caiman (Paleosuchus palpebrosus) with capture- recapture data from 40 individuals collected over 6 yr in streams surrounding the Brazilian Pantanal, near the southern limit of the species' distribution. Repeated recaptures of eight animals indicate that withinindividual variation is much greater than between-individual variation, possibly reflecting climatic influences. Growth rates of juveniles increased linearly until individuals were about 28 cm snout-vent length (SVL), and then growth rates decreased gradually after attaining that size. The rate of decrease, however, differed between males and females. Data for 30 juveniles with known age were used to validate the growth curve based on the growth rate-on-size analysis. The length of the smallest female recorded nesting (SVL=60 cm) allowed us to estimate the age at first reproduction to be about 8 yr for females. Our data do not support our initial hypothesis that P. palpebrosus would have slow growth rates and relatively old age at first reproduction, as has been suggested for Paleosuchus trigonatus. © 2013 by The Herpetologists' League, Inc. Source

Rheingantz M.L.,Federal University of Rio de Janeiro | Leuchtenberger C.,Laboratorio Of Vida Selvagem | Zucco C.A.,Federal University of Rio de Janeiro | Fernandez F.A.S.,Federal University of Rio de Janeiro
Journal of Tropical Ecology | Year: 2016

Circadian use of time is an important, but often neglected, part of an animal's niche. We compared the activity patterns of the Neotropical otter Lontra longicaudis in two different areas in Brazil using camera traps placed at the entrance of holts. We obtained 58 independent photos in the Atlantic Forest (273 camera trap-days) and 46 photos in Pantanal (300 camera trap-days). We observed different kernel density probabilities on these two areas (45.6% and 14.1% overlap between the 95% and 50% density isopleths respectively). We observed the plasticity in Neotropical otter activity behaviour with different activity patterns in the two areas. In the Pantanal, the Neotropical otter selected daylight (Ivlev = 0.23) and avoided night (Ivlev = -0.44), while in the Atlantic Forest it selected dawn (Ivlev = 0.24) and night (Ivlev = 0.14), avoiding daylight (Ivlev = -0.33). We believe that this pattern can be due to human activity or shifts in prey activity. © Cambridge University Press 2016. Source

Silveira M.,Federal University of Mato Grosso do Sul | Munin R.L.,Federal University of Mato Grosso do Sul | Tomas W.M.,Laboratorio Of Vida Selvagem | Fischer E.,Federal University of Mato Grosso do Sul | And 2 more authors.
Biota Neotropica | Year: 2011

The largest New World bat, Vampyrum spectrum, is a locally rare top predator, which occurs from Mexico to South America. Here, we report for the first time its occurrence in the southern Pantanal floodplain, basing our records on specimens that are also the first to be reported for the State of Mato Grosso do Sul, Brazil. We conducted bat surveys in two sites 120 km apart, in the Aquidauana and Nhecolândia regions. Among 2,498 bat captures, two individuals of V. spectrum were mist-netted, one at each site. These records expand southward the distribution range of V. spectrum, and in addition to other records in the Northern Pantanal border and Bolivia support that V. spectrum is widely distributed in the upper Paraguay basin. Source

Ri-os-Uzeda B.,Federal University of Mato Grosso do Sul | Ri-os-Uzeda B.,Wildlife Conservation Society | Ri-os-Uzeda B.,Amigos y Amigos | Mourao G.,Laboratorio Of Vida Selvagem
ORYX | Year: 2012

Aerial surveys have been used successfully to estimate vertebrate populations in open habitats. The marsh deer Blastocerus dichotomus, categorized as Vulnerable on the IUCN Red List, lives in such habitats and is suitable for aerial counting because it is conspicuous. This species, the largest South American deer, is native to Argentina, Boliva, Brazil, Paraguay and Peru but no reliable information has previously been available on its populations in Bolivia. From May to August 2007 we conducted aerial transects to survey marsh deer in three large areas of savannah. We used a modified mark-recapture method to improve the accuracy of the counts and estimated density and abundance. The corrected, estimated density of the marsh deer was 0.24 km-2 in the northern La Paz Department, 0.12 km-2 in Mamoré and 0.15 km-2 in Iténez. These densities are similar to the mean density of the species on other South American savannahs. This is the first large-scale survey of the marsh deer in Bolivia and the first to provide information about the density of the species in the Amazon. We recommend the creation of protected areas in these savannahs, and wildlife and domestic health programmes to conserve the marsh deer of this region. © 2012 Fauna & Flora International. Source

Campos Z.,Laboratorio Of Vida Selvagem | Muniz F.,National Institute of Amazonian Research | Desbiez A.L.J.,Royal Zoological Society of Scotland | Magnusson W.E.,National Institute of Amazonian Research
Journal of Natural History | Year: 2016

Nests of Schneider’s dwarf caiman, Paleosuchus trigonatus, were located in the forests around three streams that drain into the Xingu River, Brazilian Amazonia, in October 2014. Camera traps were installed at the edge of four nests to document predators and female parental care. At two nests, females unsuccessfully defended their nests against one or more giant armadillos, Priodontes maximus, and nine-banded armadillos, Dasypus novemcinctus. Both armadillo species responded to the attack by fleeing and returning on the opposite side of the nest by going around the tree under which the nest was located. Giant armadillos have never before been recorded consuming caiman eggs and their diet has been described as consisting mostly of ants and termites. Another species of armadillo, Cabassous unicinctus, was also registered digging into a nest and probably consuming eggs, though it is generally considered to be primarily insectivorous. A tayra (Eira barbara), lizard (Tupinambis teguixin) and coati (Nasua nasua) were also registered taking eggs from nests during the day, but we obtained no registers of nest defence by caimans during the day. The three nests were attacked after 60 days of incubation, when the eggs were well developed. © 2016 Taylor & Francis Source

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