30 research outputs found
Ocelot, Leopardus pardalis (Mammalia, Carnivora, Felidae), home range in the Lowland Atlantic Forest of Southeastern Brazil
The ocelot is an important Neotropical mesopredator and information on its spatial ecology remains scarce. Here we estimated the ocelot home range in a remnant of Lowland Atlantic Forest in Southeastern Brazil. The data were collected by camera traps installed at eight known ocelot latrines. We estimated the home range both based on the Minimum Convex Polygon (MCP) and the 95% adaptive Kernel density estimator (95%K) to compare with other published studies. We identified 22 ocelots (adult males = 8; adult females = 12; cubs = 2). Six males were recorded at more than one latrine, while all females were recorded at only one sampling point. In addition to male ocelots being recorded at a large number of points, they showed greater intrasexual spatial overlap as they used the same latrines, suggesting larger home ranges than females. The mean home range size for males was 12.1 ± SE 4.4 km2 (range = 6.2 to 20.8 km2) using MCP, and 19.9 ± SE 9.5 km2 (range = 10.1 to 38.9 km2) applying 95%K. Despite our estimates representing an approximation of the total area used by males, both values are consistent with those reported from other locations. Our data complemented the gradient of vegetation type sampled for ocelots in Atlantic Forest and support the suggestion that this environmental variable and, consequently, its effect on prey availability, influence the home range size of ocelot. Information on population ecology and other spatial ecology data are also presented
Litter Surface Temperature: A Driving Factor Affecting Foraging Activity in Dinoponera lucida (Hymenoptera: Formicidae)
Dinoponera lucida is a poneromorph ant endemic to the Atlantic Forest of Brazil. The species is classified as endangered in Brazil’s Red List due to its peculiar reproductive biology and high habitat fragmentation. Herein, we characterize D. lucida foraging activity and response to litter surface temperature in a lowland forest remnant in south-eastern Brazil. The mean flow of workers at nest openings was 3.8 ± 0.6 per hour, mean foraging trip was 14.2 ± 2.2 min, and mean foraging distance was 3.8 ± 0.4 m. The time spent per foraging trip and litter surface temperature were positively correlated. Flow of workers at nest openings was higher with mean temperature of litter surface between 21.0 and 27.0 °C. Our results show that D. lucida has a diurnal foraging activity related to habitat temperature. Our data contribute to the knowledge about the ecology of D. lucida and support the hypothesis of optimal food foraging regulated by habitat temperature. In addition, the better understanding of D. lucida activity patterns can assist on conservation planning of this endangered and endemic ant
A Day in the Life of the Giant Ant Dinoponera lucida Emery, 1901 (Hymenoptera, Formicidae): Records of Activities and Intraspecific Interactions
Ants present a wide variety of nesting sites, feeding habits, and trophic interactions, but the biology of most species remains unknown. Dinoponera lucida is a poneromorph ant forest-specialist and solitary forager, endemic to the Brazil’s Atlantic Forest. Herein we describe foraging activities, guard and maintenance of the nests, orientation mode, and intraspecific interactions performed by D. lucida. We found three nests distant from each other at least 8.5 m, and the mean reached distance by a worker was 3.8 m. The workers showed colony fidelity and random forage in their territory. We observed two non-agonistic interactions between workers from the same nest, and two agonistic interactions between foraging workers from different nests. The low frequency of agonistic interactions suggests that workers from different nests are unlikely to forage in the same area. Our results expand the knowledge on ants’ natural history through data on foraging activities, guard and maintenance of the nests, orientation mode and intraspecific interactions
Harpy Eagle sightings, traces and nesting records at the "Reserva Natural Vale", a Brazilian Atlantic Forest remnant in EspĂrito Santo, Brazil
We present 25 records of sightings, feathers and nests of the Harpy Eagle Harpia harpyja in the last 27 years and also the first detailed description of a nest of a Harpy Eagle in the Brazilian Atlantic Forest, found at the "Reserva Natural Vale" (RNV), Linhares, EspĂrito Santo, Brazil. Most Harpy Eagle records were obtained along the RNV roads by researchers and the RNV staff. Two nests have been mapped at the RNV until now. An especially relevant record occurred in 1997 when a juvenile Harpy Eagle was found dead, 4 km distant from the nest mapped and measured in 2010. The nest was 1.8 m Ă— 1.6 m in diameter, and was built 28 m above ground, on the main fork of an Astronium concinnum tree measuring 37 m height and 1 m in diameter at breast height (DBH). This nest was the second of the species to be reported at RNV, being 5 km away from the first one, found in 1992, and built 30 m above the ground on the main fork of a Cariniana legalis tree 36 m high and 1.1 m in DBH. All Harpy Eagle records at RNV indicate that this protected area offers enough resources and has carrying capacity to maintain at least two Harpy Eagle pairs. However, because of the fragmentation around RNV, the local Harpy Eagle population cannot expand due to reduced habitat availability. The data gathered in this study confirm the importance of the RNV for the conservation of the critically endangered Harpy Eagle population of the Brazilian Atlantic Forest. We recommend the establishment of a reforestation program to increase the size and the connections of fragments around the RNV. We suggest that the creation and effective implementation of protected areas may contribute to Harpy Eagle protection in the Brazilian Atlantic Forest, but the long-term conservation of remaining populations is an essential step to allow for the occupation and re-colonization of other areas
ATLANTIC-PRIMATES: a dataset of communities and occurrences of primates in the Atlantic Forests of South America
Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1–6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km 2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km 2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. © 2018 by the The Authors. Ecology © 2018 The Ecological Society of Americ
Influence of camera-trap sampling design on mammal species capture rates and community structures in southeastern Brazil
The distribution of species and population attributes are critical data for biodiversity conservation. As a tool for obtaining such data, camera traps have become increasingly common throughout the world. However, there are disagreements on how camera-trap records should be used due to imperfect species detectability and limitations regarding the use of capture rates as surrogates for abundance. We evaluated variations in the capture rates and community structures of mammals in camera-trap surveys using four different sampling designs. The camera traps were installed on internal roads (in the first and fourth years of the study), at 100-200 m from roads (internal edges; second year) and at 500 m from the nearest internal road (forest interior; third year). The mammal communities sampled in the internal edges and forest interior were similar to each other but differed significantly from those sampled on the roads. Furthermore, for most species, the number of records and the capture success varied widely among the four sampling designs. A further experiment showed that camera traps placed on the same tree trunk but facing in opposing directions also recorded few species in common. Our results demonstrated that presence or non-detection and capture rates vary among the different sampling designs. These differences resulted mostly from the habitat use and behavioral attributes of species in association with differences in sampling surveys, which resulted in differential detectability. We also recorded variations in the distribution of records per sampling point and at the same spot, evidencing the stochasticity associated with the camera-trap location and orientation. These findings reinforce that for species whose specimens cannot be individually identified, the capture rates should be best used as inputs for presence and detection analyses and for behavior inferences (regarding the preferential use of habitats and activity patterns, for example). Comparisons between capture rates or among relative abundance indices, even for the same species, should be made cautiously
Habitat use, non-breeding groupings and chromatic pattern in Johngarthia lagostoma (H. Milne Edwards, 1837) (Decapoda, Gecarcinidae) in Trindade Island, South Atlantic Ocean
The land crab Johngarthia lagostoma is endemic to Trindade Island, Atol das Rocas, Fernando de Noronha and Ascension Islands. The natural history of the species in non-breeding periods is little known. Therefore, here we reported the formation of non-breeding groups and evaluated the chromatic populational pattern of J. lagostoma in Trindade Island. Records were obtained between April and June 2015. The groups were characterized according to their location, terrain elevation, environmental characteristics and specimens’ behavior. The chromatic pattern was defined by the classification of individuals between yellow and purple, and the proportion of each color was compared between populational units (previously defined based on genetic differences). Non-breeding groups were recorded in four locations in Trindade Island, at altitudes < 40 m, and all of them were in locations with food resources and sediment suitable for the construction of shelters. Isolated individuals or the absence of the species were observed in the most inhospitable places, indicating that the maintenance of the species depends on portions of suitable habitat amid the currently arid matrix. Yellow individuals (96.4%) were predominant on Trindade Island and the chromatic pattern differed from the other populations. Color patterns seem to follow genetic differences between populations, and the founder effect may account for current patterns. From the data obtained, we emphasize that the maintenance of the species may depend on food, sediment suitable for shelters construction, humidity and shade. Due to the significant population decline in other regions, the need to define guidelines for the conservation of the species on Trindade Island is highlighted. In this context, the regeneration of insular vegetation and prohibiting the known anthropic consumption of individuals may represent important strategies for the maintenance of the species