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Abstract The American Barn Owl (Tyto furcata) lives in urban, periurban and wild environments and feeds mainly on small rodents, meaning it has great importance in the biological control of pests. The aim of this work was to describe the reproductive, parental and eating habits of a pair of American barn owls naturally living outside a residence in the urban area of the municipality of Campos dos Goytacazes, Rio de Janeiro state, Brazil. A wood box was installed on an outside wall of the home, monitored by a video camera. A spreadsheet was created to keep track of the observations recorded. The female laid four eggs, and after an incubation period of 30-32 days all the eggs hatched, but only two chicks survived after cannibalism among the chicks. Initially, the male provided the food to the chicks and the female remained in the nest caring for the brood. After approximately a month, the female also began to leave the nest and return with prey, which was offered to the chicks, with the male also continuing this behavior. The chicks left the nest in September, 2017. The data obtained show the existence of cooperation and division of tasks between male and female owls during the reproductive period.

Abstract There are few studies in tropical regions exploring the use of leaf breakdown process as a functional tool to assess anthropic disturbance on aquatic ecosystems. We assessed the effects of water pollution due to human activities on the leaf breakdown rate of Picramnia sellowii in streams of the southeastern Brazil. The experiment was carried out for 60 days in three reference streams and three streams impaired by organic pollution and absence of riparian vegetation. Three litter bags were incubated in each stream containing 3 ± 0.05 g of P. sellowii leaves. The reference streams presented higher values of dissolved oxygen and lower values of nutrients, turbidity, electrical conductivity, total impermeable area and water temperature. The leaf breakdown rate (k) differed significantly between the reference (k = 0.014 ± 0.003 d–1) and impaired streams (k = 0.005 ± 0.001 d–1). The leaves incubated in the reference streams contained greater fungal biomass (measured as ergosterol concentration) and abundance of invertebrates, as well as greater presence of shredders, with k values being related to the biomass of these organisms. Overall, there were clear differences between the leaf mass loss in the reference and impaired streams. These results reinforce the negative effect of urbanization on leaf breakdown and fungal and shredder biomass.

Abstract Variations of age and total length of Sotalia guianensis from the state of Espírito Santo, Brazil, were evaluated. Specimens were found stranded. Age and total length of 44 Guiana dolphins were assessed based on tooth analysis. Age varied between 0.5 year and 33 years (mean = 8.23 years). Most specimens were between zero and 6 years old (47%). Total length varied from 119 cm to 198 cm, with mean of 172.52 cm. Asymptotic length was reached at 185 cm and approximately 5-6 years of age. Mean total length and age were higher than in other regions of the distribution range of the species. Nevertheless, more studies have to be carried out to evaluate the morphological variations in S. guianensis populations in the study area and Brazil.