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The hoary fox, Lycalopex vetulus, is a small insectivorous canid endemic to grasslands of Central Brazil. Herein we characterize hoary fox social behavior, based on qualitative and quantitative differences in intraspecific communication among males, females, and subadults. A family group, two reproductive pairs and three other adult individuals of unidentified social status were directly observed from 1995 to 2001, for the continuous recording of all occurrences of behavioral events. Hoary fox exhibited behaviors related to communication and food consumption. A total of 4,240 behavioral events were recorded, most in the categories 'Consumption' (58%) and 'Olfactory' (23%). The frequencies of signaling types varied among individuals according to sex, age, and socioecological phase. Olfactory signalings were more frequent in adult males, and during the Mating and Dispersal phases. Acoustic signalings were more frequent in adult females and individuals rearing the young. 'Consumption' and 'Tactile' behaviors were more frequent in subadults. The hoary fox intraspecific communication is characteristic of solitary canids, but during mating season and rearing period, individuals become more 'socialized.' Data on courtship and mating, partnership dissolution phase, and the breakup of the family group until young dispersal, are necessary for a better understanding of intraspecific communication of the hoary fox. [ABSTRACT FROM AUTHOR]

We radio-tracked a pack of bush dogs Speothos venaticus (7–10 individuals) near Água Boa in Mato Grosso, Brazil, for 18 months to investigate their use of habitat in cultivated land. The pack's home range was 709 km2 (fixed-kernel 95%), which exceeds estimates of home range for the largest Neotropical carnivore, the jaguar Panthera onca. Of the 245 locations where the dogs were recorded 95% were within native vegetation (savannah and forest), even though these habitats comprised only 34% of the pack's home range. This indicates a preference for native vegetation, and this was reinforced by composition analysis of habitat use, which showed that the pack used savannah and forest more than expected and cultivated areas less than expected. Analysis of activity showed that the bush dogs were moving quickly in more than half of the locations in cultivated areas, foraging in most savannah locations and resting in most forest locations. Our results indicate that bush dogs can live in areas with a high proportion of cultivated land (66%), possibly because of the structural connectivity of the landscape (80% of the native habitat is within a single patch). However, their home range appears to be inflated compared to that of other carnivores, which may have a negative effect on the species in the long term. [ABSTRACT FROM AUTHOR]

Abstract: Calcium carbonate (CaCO3)/high density polyethylene (HDPE) composites were prepared in a HAAKE twin screw extruder. The influence of the CaCO3 particle size and content and the processing conditions were investigated by using a factorial experimental design. The dependent variables studied were tensile properties, such as Young''s modulus, stress at break and toughness, and the rheological property, zero-shear viscosity, η 0. Preliminary results have shown that the most significant processing variables were content and mineral filler type. Mathematical modeling has given us a more efficient evaluation of the results obtained and has become an important tool in the development of this work. [Copyright &y& Elsevier]