Emygdio L. A. Monteiro-Filho

Vertical stratification of small mammals in the Atlantic rain forest of south-eastern Brazil

Patterns of vertical stratification and canopy utilization by rodents and marsupials were analysed in two contiguous Atlantic forests at different altitudes (100 m and 900 m asl). Twenty-two species were captured using live traps placed at ground level, in the understorey (1.5–2.0 m), and in the canopy (6–15 m) over 2 y; seven species (32%) were mainly or exclusively arboreal. Community composition and relative abundance of species in the different vertical strata were not similar, with a general reduction in the number of species, and in abundance in the upper layers. The following species were captured mainly or exclusively in the canopy: Micoureus demerarae and Gracilinanus microtarsus (Didelphimorphia, Didelphidae); Wilfredomys pictipes , Oecomys aff. concolor , and Rhipidomys aff. macrurus (Rodentia, Muridae); and Nelomys nigrispinus (Rodentia, Echimyidae). Our results indicated that altitudinal changes in Atlantic forest areas may alter the community composition of different forest layers but they do not seem to alter greatly specific patterns of vertical habitat utilization. Similar-sized species tended to differ in their patterns of vertical utilization of habitat with the exception of terrestrial akodontine rodents (genera Akodon , Thaptomys , Oxymycterus and Brucepattersonius ). Rodents (mainly Oryzomys russatus ) dominated captures at ground level at both sites but Akodontinii were numerous only at the highest site. Unlike other neotropical forests, marsupials did not dominate canopy captures.

SKULL SHAPE AND SIZE DIVERGENCE IN DOLPHINS OF THE GENUS SOTALIA: A TRIDIMENSIONAL MORPHOMETRIC ANALYSIS

Abstract A study of cranial shape in dolphins of genus Sotalia was done using 104 specimens (92 from localities along the Brazilian coast and 12 from the Amazon River basin). Twenty-two cranial landmarks, assumed to be homologous, were selected for analysis. The first 2 principal components of aligned coordinates explained 40.6% of the total variation in cranial shape. Although no sexual dimorphism was detected (P = 0.811), shape differences among populations of Sotalia were highly significant (P < 0.000001). The 1st and 2nd principal components of shape showed that the Sotalia population from the Amazon basin differed in cranial shape from marine populations. Based on differences in geometric shape, a discriminant analysis of 3 linear measurements between landmarks provided an equation that classified skulls as belonging to Amazonian or marine populations. Based on these results and evidence from several other divergent character systems and life history attributes, we suggest the use of Sotalia guianensis for marine dolphins and S. fluviatilis for Amazonian dolphins.

A preliminary analysis of insects of medico-legal importance in Curitiba, State of Parana

A survey of the carrion fauna was made at two sites in Curitiba, State of Paraná, with the objective of describing the insects associated with carrion and setting up a preliminary data-base for medico-legal purposes in south Brazil. Vertebrate exclusion experiments were carried out in each season between 1994 and 1995 with a 250 g laboratory-bred rat (Rattus norvegicus). Five stages of decomposition were identified: fresh, bloated, decaying, dry and adipocere-like. Some species showed seasonal and site preference and so could be used to identify the probable place and season where death took place. Sarconesia chlorogaster (Diptera, Calliphoridae) was restricted to an open field site and to cooler months. Hemilucilia semidiaphana (Diptera, Calliphoridae) and Pattonella resona (Diptera, Sarcophagidae) were restricted to the forest site and warmer months. Phaenicia eximia (Diptera, Calliphoridae) and Oxyletrum discicolle (Coleoptera, Silphidae) were present at both sites throughout the year and could be useful for population level analysis. Dissochaetus murray (Coleoptera, Cholevidae) was present throughout the year at the forest site and was associated with the adipocere-like stage. Ants played an important role producing post-mortem injuries to the carcasses. Insects of 32 species are reported as being useful in community level approaches.

REPRODUCTION OF THE ESTUARINE DOLPHIN (SOTALIA GUIANENSIS) ON THE COAST OF PARANÁ, SOUTHERN BRAZIL

Abstract The estuarine dolphin (Sotalia guianensis) is common along most of the Brazilian coast, but little is known about its reproduction. We analyzed the gonads of 50 individuals incidentally caught in fishing nets on the coast of Paraná, southern Brazil, between 1997 and 1999. Testes of adult males were ≤31.9 cm in length and ≤11.6 cm in width and ≤3.3% of the total body mass. Relative size of testes suggests a multimale mating system with sperm competition. Females ovulate in both ovaries, although the left ovary matures earlier than the right. Males reached sexual maturity at 7 years and at body lengths estimated at 170–175 cm. Females matured at 5–8 years of age and at body lengths of 164–169 cm. The reproductive cycle was estimated at 2 years, with no marked seasonality in ovulation or timing of birth. Gestation was about 12 months, fetal growth rate was 9 cm/month, and length at birth was estimated at 92.2 cm. Females older than 25 years had senescent ovaries.

Food Habits, Home Range and Activity of Didelphis aurita (Mammalia, Marsupialia) in a Forest Fragment of Southern Brazil

Relationships between food habits, home range and activity of the black-eared opossum, Didelphis aurita (Marsupialia, Didelphidae), were studied in an urban forest fragment (5 ha) of southern Brazil from February 1995 to January 1996. Captures were performed weekly using 30 live-traps placed uniformly in the study area. Diet was determined through faecal analysis, home ranges were calculated through the Minimum Convex Polygon method and the activity period was assessed from the time of captures in the night. The opossum proved to be an insectivorous-omnivorous marsupial consuming invertebrates (100%), fruits (78%) and vertebrates (59%). Birds, mammals, Coleoptera, Diplopoda, Opiliones and Solanaceous fruits were the main items consumed. Opossums foraged during the first hours of the night in part synchronizing their activity with that of small mammals occasionally preyed upon. Home ranges measured from 0.2 ha for a female to 3.0 ha for a male. Males appeared in the study area only during the wet season, increasing their home range size, whereas females revealed quite exclusive home ranges that could imply the defence of a territory.

Diet of the Neotropical Otter, Lontra longicaudis, in an Atlantic Forest Area, Santa Catarina State, Southern Brazil

The diet of the neotropical otter (Carnivora, Mustelidae) was studied from September 1995 to March 1997, in Volta Velha, an Atlantic Forest reserve in the coastal plain of Santa Catarina State, southern Brazil. Fecal samples were collected monthly along the rivers Saí-Mirim, Braço do Norte and Volta Velha. Additionally, from October 1996 to June 1997, a qualitative and quantitative study of fish species available in the studied rivers was performed. The analysis of 202 collected fecal samples indicated a diet based on fish (mainly Hoplias malabaricus and Geophagus brasiliensis) and crustaceans (mainly Trichodactylus fluviatilis, a river crab), characterizing the neotropical otter as piscivorous-cancrivorous in the study area. The presence of fruits, reptiles, birds and mammals in the diet is occasional and opportunistic. Probably the higher consumption of a certain fish species compared to its availability and the high percentage of occurrence of T. fluviatilis in scats of the neotropical otter reflect their higher catchability.

Residence and site fidelity of Sotalia guianensis in the Caravelas River Estuary, eastern Brazil

Between April 2002 and April 2005, 210 estuarine dolphin groups were sighted, with 58 animals individually identified. Fifteen dolphins were photo-identified just once, while only two animals were sighted in 15 different months. Some individuals showed long-term residence (more than 3 y). Residence rates showed heterogeneity in the dolphin’s permanence of the estuary, with 60% of the individuals with low numbers (<10) and only 7% showing high values for residence (maximum=45.9). Continued resightings of some dolphins support the regular use of the study area by the animals, despite some individuals that, after a long time without resightings were registered again. Individual range analysis showed that dolphins shared the same common area, the Caravelas River Estuary. A marked fluctuation in the number of photo-identified dolphins was observed in the study area, revealed by the high number of individuals with just a few resightings. The majority of the dolphins (60%) present a yearly residence pattern, as observed in other areas, suggesting that a few individuals show high fidelity for the area, while many other dolphins move constantly between different areas for unknown reasons.

Pesca associada entre golfinhos e aves marinhas

Along ten years of study of a common dolphin from the brazilian coast, Sotalia brasiliensis Van Beneden, 1874, I could see some occasions of feeding associations of this dolphin with five species of birds, Sula leucogaster (Boddaert, 1783), Fregata magnificens Mathews, 1914, Sterna hirundinacea Lesson, 1831, Larus dominicanus Lichtenstein, 1823 and Phalacrocorax olivaceus Humboldt, 1895. The commonest association observed was between the dolphin and S. leucogaster, and in all the associations was characterized the commensalism, with advantaged to the birds.

Heterotrophic succession in carrion arthropod assemblages

A Sucessao ecologica em comunidades efemeras tem sido tratada como um processo discreto por varios autores, mesmo em detrimento de algumas evidencias que apontam para um processo continuo. Esta controversia aparentemente deve-se ao uso forense dos dados de sucessao. Baseado nestes fatos, nos analisamos dados da sucessao de insetos sobre carcacas em dois locais contrastantes fisionomicamente para determinar a natureza do processo de sucessao: se discreto ou continuo. Os padroes de visitacao demostraram uma complementaridade no padrao de chegada entre especies saprofagas e predadoras e que a taxa de recorrentes variou entre 40% e 46% com excecao do inverno com valores proximos a 95%. A area florestada sempre apresentou maior riqueza que a area urbana e, em ambas as areas, a tendencia ao aumento da riqueza seguiu um padrao exponencial com um declinio posterior. O padrao de chegada indica uma agregacao de especies nos primeiros estagios de decomposicao. Em ambas as areas nao foram encontradas separacoes claras entre as fases que compoem o processo de decomposicao, sugerindo assim, um processo continuo e sugerindo tambem, que a facilitacao nao e o processo que estaria gerando o padrao observado.

Home Range and Activity Patterns of Pampas Deer in Emas National Park, Brazil

Abstract Home range, movements, and activity patterns of pampas deer (Ozotoceros bezoarticus) were studied in Emas National Park, State of Goiás, Brazil. Four pampas deer were located daily during 1 year by radio tracking. Additionally, during 8 sampling periods, locations were determined every 30 min for 12 consecutive hours to determine activity patterns. Vegetation was sampled monthly to detect for seasonal variation in food availability. Pampas deer were active during the day and night, and individual variation in activity patterns was observed. Average home ranges of pampas deer were larger than the average area used by other Odocoileinae. Home ranges were similar in size in the dry (April–September) and wet (October–March) seasons, but deer moved more during the rainy season—a pattern apparently related to availability of flowers.