1. Brazil is the second most bat species-rich country in the world, but the available information on the occurrence and distribution of bat species in Brazil is still heterogeneous and fragmented. 2. We review the occurrence and distribution of bat species in Brazil, analyse the spatial performance of inventories conducted to date and identify knowledge gaps. We also identify the main factors contributing to the recent increase in the knowledge of the Brazilian bat fauna, and make suggestions for maintaining this momentum into the near future. 3. We plotted record coordinates on a map, grouped them in 0.5 degrees of latitude ¥ 0.5 degrees of longitude grid cells, and analysed records for each of the five terrestrial biomes in Brazil, and for the 1439 priority polygons for the conservation of Brazilian biodiversity. 4. We identified 5502 formal bat records in Brazil, indicating that less than 10% of the country is minimally surveyed, and that for nearly 60% of Brazil there is not a single record of bat species. Record coverage varies from 79% in the Atlantic Forest to 24% in Amazonia, but none of the Brazilian biomes is well surveyed for bats. Bat species have been recorded in only 15% of the priority areas for Brazilian biodiversity conservation. 5. If the current rate of recording bats in empty grid cells (10% every 4 years) was maintained, it would take 33 years for all cells to have a single record. If the current rate of recording Ն20 species in a grid cell (0.8% per year) was maintained, it would take 200 years for the bat fauna of Brazil to be minimally surveyed. Alarmingly, most of the data-poor areas are at the expansion frontiers of the agro-business, near the surrounding deforestation fronts. 6. We make recommendations for scientific research on bats in Brazil, to ensure the conservation of this ecologically important taxon.

Summary1. Species richness is a state variable of some interest in monitoring programmes but raw species counts are often biased due to imperfect species detectability. Therefore, monitoring programmes should quantify detectability for target taxa to assess whether it varies over temporal or spatial scales. We assessed the potential for tropical bat monitoring programmes to reliably estimate trends in species richness. 2. Using data from 25 bat assemblages from the Old and New World tropics, we estimated detectability for all species in an assemblage (mean proportion of species detected per sampling plot) and for individual species (species-specific detectability). We further assessed how these estimates of detectability were affected by external sources of variation relating to time, space, survey effort and biological traits. 3. The mean proportion of species detected across 96 sampling plots was estimated at 0AE76 (range 0AE57-1AE00) and was significantly greater for phytophagous than for animalivorous species. Species-*Correspondence author. E-mail: cmeyer@fc.ul.pt 1365-2664.2011.01976.x Ó 2011 The Authors. Journal of Applied Ecology Ó 2011 British Ecological Society averaged detectability for phytophagous species was influenced by the number of surveys and season, whereas the number of surveys and sampling methods [ground-or canopy-level mist nets, harp traps and acoustic sampling (AS)] most strongly affected estimates of detectability for animalivorous bats. Species-specific detectability averaged 0AE4 and was highly heterogeneous across 232 species, with estimates ranging from 0AE03 to 0AE84. Species-level detectability was influenced by a range of external factors such as location, season, or sampling method, suggesting that raw species counts may sometimes be strongly biased. 4. Synthesis and applications. Due to generally high species-specific detection probabilities, Neotropical aerial insectivorous bats proved to be well suited for monitoring using AS. However, for species with low detectability, such as most gleaning animalivores or nectarivores, count data obtained in bat monitoring surveys must be corrected for detection bias. Our results indicate that species-averaged detection probabilities will rarely approach 1 unless many surveys are conducted. Consequently, long-term bat monitoring programmes need to adopt an estimation scheme that corrects for variation in detectability when comparing species richness over time and when making regional comparisons. Similar corrections will be needed for other species-rich tropical taxa. Journal of AppliedEcology 2011, 48, 777-787 doi: 10.1111/j.

Carcass persistence time and detectability are two main sources of uncertainty on roadkill surveys. In this study, we evaluate the influence of these uncertainties on roadkill surveys and estimates. To estimate carcass persistence time, three observers (including the driver) surveyed 114km by car on a monthly basis for two years, searching for wildlife-vehicle collisions (WVC). Each survey consisted of five consecutive days. To estimate carcass detectability, we randomly selected stretches of 500m to be also surveyed on foot by two other observers (total 292 walked stretches, 146 km walked). We expected that body size of the carcass, road type, presence of scavengers and weather conditions to be the main drivers influencing the carcass persistence times, but their relative importance was unknown. We also expected detectability to be highly dependent on body size. Overall, we recorded low median persistence times (one day) and low detectability (<10%) for all vertebrates. The results indicate that body size and landscape cover (as a surrogate of scavengers’ presence) are the major drivers of carcass persistence. Detectability was lower for animals with body mass less than 100g when compared to carcass with higher body mass. We estimated that our recorded mortality rates underestimated actual values of mortality by 2–10 fold. Although persistence times were similar to previous studies, the detectability rates here described are very different from previous studies. The results suggest that detectability is the main source of bias across WVC studies. Therefore, more than persistence times, studies should carefully account for differing detectability when comparing WVC studies.

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