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Cavia intermedia is a rare cavy, endemic to the 10-ha Moleques do Sul Island, southern Brazil. We conducted the 1st study of reproductive and growth patterns for this species in its natural environment. Based on 17 months of monthly population monitoring using capture-mark-recapture methods, females were reproductively active throughout the year. Litter size was small (1 or 2 young per litter), with well-developed offspring that weighed approximately 19% of the mass of an adult female. Sexual maturity was reached later than in other species of this genus, at around 59 days of age or 70% of adult body size. There was no evidence that longevity was longer than for congeneric species. Other than longevity, these characteristics are consistent with the island syndrome, which may contribute to the persistence of this species. Key words: body development, endemism, Hystricomorpha, island syndrome, life history, life span, litter size, precocity, sexual maturity, wild guinea pig

Cavia intermedia may be the mammal with the smallest geographical distribution in the world, because it is endemic to a 10-ha island and therefore vulnerable to extinction. The objective of this study was to understand the population dynamics of C. intermedia in order to define its conservation status and to provide information for its management. The population was sampled monthly using capture-mark-recapture methods and radiotelemetry for 16 months, between March 2004 and June 2005. A total of 5,530 trap-nights resulted in 665 captures of 141 individuals. The population exhibited the main demographic characteristics of the insular syndrome, such as high and stable density, small home ranges, stable age structure composed mostly of adults, and high survival rates. The population dynamics were characterized by density-dependent effects on mortality. C. intermedia can be considered one of the rarest species on the planet because of its limited geographic distribution and very small population size (average estimated population of 42 individuals). We recommend that it be listed as Critically Endangered. Key words: age structure, density dependence, endemism, Histricomorpha, home range, island, island syndrome, population size, rarity, wild guinea pig

The huge mudslides and flooding in Brazil that killed more than 890 people in Rio de Janeiro state have been blamed on heavy rains and soil features. We believe that [...]

The diet of the marsupial Micoureus demerarae was studied from fecal samples obtained from live-trapping in Atlantic Coastal Forest fragments at Poço das Antas Biological Reserve, southeastern Brazil, from 1995 to 1997. Among arthropods, the most frequent food items belonged to the orders Coleoptera and Hymenoptera, whereas Arachnida, Orthoptera, Hemiptera and Lepidoptera were also frequent. Lepidoptera and Diptera were represented mostly by larvae and pupae. Crustaceans of the orders Copepoda and Isopoda were also found. Plants were represented by seeds of species from secondary vegetation, mostly belonging to the families Piperaceae, Moraceae and Cecropiaceae, which should reflect frugivory. Predominance of arthropods in the diet was consistent with previous studies. Diet composition was remarkably constant among fragments, sexes, age classes, breeding versus non-breeding seasons, and climatic categories (dry versus humid months). The only significant difference was that diversity of arthropods was higher in the non-breeding than in the breeding season, but this was likely to be due to sampling effects. Given the natural abundances of the food items, the constancy of the diet is likely to reflect opportunism rather than food selection. [ABSTRACT FROM AUTHOR]