Elizabete Captivo Lourenço

Bat diversity of Ilha da Marambaia, Southern Rio de Janeiro State, Brazil (Chiroptera, Mammalia).

Few sites have been well sampled for bats, and samplings in islands are even scarcer. Therefore, the objectives of the present study were: (1) to list the bat species of Ilha da Marambaia; (2) to compare richness, abundance and biomass of bat guilds found there; (3) to analyse abundance patterns of bat species; and (4) to compare richness, abundance and composition of the bat fauna among different kinds of environment. To capture bats we used mist nets set in five different environments, totalising 3559.2 net-hours, during 37 nights between October 2006 and August 2008. A total of 1,133 captures were accomplished, comprising 34 species from five families. The most abundant species was Molossus molossus. Frugivorous bats exhibited higher richness, abundance and biomass if compared to other guilds. Most species (N = 22) exhibited abundances between 1 to 10% of all captures. Sixteen species were restricted to just one of the environments sampled. The high richness may be attributed to sampling carried out in several environments, and to the capture of insectivorous species over water bodies.

Colony size, sex ratio and cohabitation in roosts of Phyllostomus hastatus (Pallas) (Chiroptera: Phyllostomidae)

Phyllostomus hastatus bat is species broadly distributed over the Neotropical region, which uses as diurnal roosts caves, hollow trees, palm leaves and human buildings. Thirteen diurnal roosts of P. hastatus were analysed from 1990 to 2009 in several localities of Rio de Janeiro State, regarding environment (rural, urban or protected area), type of roost (hollow tree, basement or roof), sex ratio and cohabitation. A nocturnal roost was also analysed. Sex ratio of P. hastatus varied considerably among roosts what may be explained by the fact this species can roost alone, in couples, in harems or in groups of bachelor males. Phyllostomus hastatus was observed in cohabitation with three other species: Molossus rufus, Molossus molossus and Myotis nigricans. Due to the frequency of cohabitation observed between P. hastatus and species of the genus Molossus, one or more advantages for the members of this association may be expected. The simultaneous usage of a feeding roost by a group of bachelor males is unknown information in the literature, and may suggest that this kind of group may interact with each other even when away from their diurnal roosts.

Bats from the Restinga of Praia das Neves, state of Espírito Santo, Southeastern Brazil

Studies on bat richness and diversity in coastal sand dunes (‘ restinga’ ) are still scarce. Therefore, the objectives of the present study were to estimate bat richness in the restinga of Praia das Neves (state of Espirito Santo, southeastern Brazil) and to analyze species abundance. Ten sampling nights were carried out in May and July 2008, resulting in a sampling effort of 21,847.5 h.m2. We captured 125 individuals from 17 bat species. In this study, Tonatia saurophila was recorded for the first time not only in the state of Espirito Santo but also in the restinga ecosystem. The most abundant species was Artibeus lituratus with 32% of all captures. Surveys in coastal restingas are urgently needed in order to obtain more information about the bats living in this environment.

Streblidae (Diptera) on bats (Chiroptera) in an area of Atlantic Forest, state of Rio de Janeiro

Because of the few records of Streblidae on bats, despite extensive study on these mammals in the state of Rio de Janeiro, a survey was carried out in an area of Atlantic Forest, in the municipality of Nova Iguaçu, known as the Tinguá region. Thirteen species were added to the list of Streblidae in the state of Rio de Janeiro, of which two were new records for Brazil. Thirty-one species have now been reported this state.

Composition of bat assemblages (Mammalia: Chiroptera) in tropical riparian forests

Various studies have focused on the richness and abundance of bats in tropical forests and how the composition of these forests affects bat assemblages, but there are few studies on the relationship of bats with riparian forests. The aim of this study was to ascertain the differences among bat assemblages of three riparian forest areas of the Tingua region, state of Rio de Janeiro, Brazil. These areas were: I) an agricultural area (Takume); II) a reforested area in primary succession (Canavarro); and III) an area with late secondary vegetation (Tingua Biological Reserve). Assessments of bat species composition in these areas may shed light on how anthropogenic modifications in riparian forests can influence local bat assemblages. Bats were captured with mist nets during 72 sampling nights. Total bat abundance was 1,511 individuals in 26 species. The three areas differed in their species composition. The Tingua Biological Reserve was the richest area, Canavarro presented the lowest diversity and the highest abundance of individuals, and the evenness index was highest in Takume. The differences found in the composition and ecological indices indicate that bat assemblages have distinct characteristics in the three areas studied, with varied degrees of transformation and anthropization.

Reinfestation of Streblidae ectoparasites (Diptera) in Carollia perspicillata (Linnaeus, 1758) (Chiroptera)

The mark-recapture method allows analysis on the variation in the abundance of bat ectoparasites at consecutive captures. The objectives of this study were to compare the pattern of Streblidae parasitism between capture and recapture of C. perspicillata; ascertain whether the abundance of Streblidae varied with time after removal of ectoparasites at capture and analyze whether the intensity of parasitism remained the same in each individual at capture and recapture. Using bats netted in the State of Rio de Janeiro, 42 individuals of C. perspicillata parasitized by two Streblidae species, Trichobius joblingi Wenzel, 1966 and Strebla guajiro (Garcia & Casal, 1965), were selected. The pattern of parasitism observed at capture was similar at recapture. No relationship was observed between the capture-recapture time interval and the abundance of ectoparasites. There was no relationship between the abundances of ectoparasites at capture and recapture of each individual.

Activity of two species of free-tailed bats over a stream in southeastern Brazil

The objective of the present study was to investigate activity time of the molossid bats Nyctinomops laticaudatus and Molossus molossus at the same locality, and to test whether activity of one species affects activity of the other. During January 2007-May 2009, we sampled for 15 nights over a stream in southeastern Brazil. Total sampling effort was 166 h and 693 m of nets. Time of capture was transformed into minutes in relation to sunset. First captures of M. molossus occurred just after sunset except for one individual that was captured before sunset. Total activity time of M. molossus ranged from 27 min before sunset to 743 min after sunset. Total activity time of N. laticaudatus ranged from 42 to 675 min after sunset and activity differed significantly between species. Activity of M. molossus was related to time of sunset, as expected based on behavior of other insectivorous species, whereas activity of N. laticaudatus seemed independent of sunset.

Free-living ixodid ticks in an urban Atlantic Forest fragment, state of Rio de Janeiro, Brazil

As a consequence of the importance of ticks in forests in protected areas, was conducted survey of species of free-living ticks in the Natural Park Municipal Curió, state of Rio de Janeiro, Brazil. Monthly samples were taken by dragging method, dry ice traps and visual search in two transects. Adults and nymphs of Amblyomma cajennense (n= 147), Amblyomma brasiliense (n= 4) and Amblyomma parvum (n= 1) were collected. This is the first occurrence of A. parvum in the state. No correlation was found between the abundance of stages of A. cajennense and rainfall, temperature and relative humidity. The highest abundances of adults were in the months of January and May, and nymphs in September and October. The low diversity of parasites on Curió Park can be attributed to the proximity of households with pets, which would also explain the higher abundance of A. cajennense that is commonly found in areas impacted by anthropogenic pressure.

Community components of spinturnicid mites (Acari: Mesostigmata) parasitizing bats (Chiroptera) in the Tinguá Biological Reserve of Atlantic Forest of Brazil

ABSTRACT Variations in the abundance of spinturnicid mites can derive from factors inherent to the environment, such as vegetation type and climate, in addition to the intrinsic host factors. Based on the premise that different landscapes can determine the abundance, richness and parasitological indices of spinturnicid species on phyllostomid bats, these bats were analysed in three tropical forest areas. Of the 744 bats captured, 210 (28.2%) were parasitized by 727 spinturnicid mites of five species. These mites were collected on 14 of 22 bat species. The prevalence (37.6%), mean intensity (3.6), mean abundance of infestation (1.4), abundance of bats (n = 340), abundance of mites (n = 465) and infested bats (n = 128) were higher in the reforested area, although this area obtained the lowest values for richness of mite species (n = 2). The results reinforce the presence of host specificity of spinturnicid mites on phyllostomid bats.

Amblyomma nodosum (Neumann, 1899): observations on life cycle under laboratory conditions

The natural hosts of Amblyomma nodosum in the immature stages are a variety of birds and the anteater in the adult stage. However, so far no data have been published about this ticks life cycle. To fill this gap, a record was made of its development under laboratory conditions. All the procedures were controlled in a BOD chamber set at 27±1 °C and 80±10% relative humidity and scotophase. The parasitic stages were raised on rabbits (Oryctolagus cuniculus Linnaeus, 1758), from which more than 50% of larvae and nymphs were recovered, although only a small portion performed ecdysis. The adults did not fixed on the rabbits, which suggests that the experimental conditions were unsuitable for the requirements of this species. The data obtained here indicate that A. nodosum is highly dependent on its host and environment whereas under laboratory conditions and host chosen for the study was not obtained satisfactory results and new studies with different hosts and new environmental conditions should be elaborated.