8 research outputs found

    Spatial Distribution of Acromyrmex balzani (Emery) (Hymenoptera: Formicidae: Attini) Nests Using Two Sampling Methods

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    The spatial distribution (SD) of organisms is a key parameter in studies of population ecology. Among the methods to describe the SD of sessile organisms, sampling by way of plots and transects are widely used. The measurement of the distance between individuals (“nearest neighbor”) is a simple method that has not been employed in population studies with ants.  This study aimed to evaluate the SD of ant mounds of Acromyrmex balzani (Emery, 1890), using both plot sampling and nearest neighbor methods in order to evaluate which method is more appropriate for determining SD of this species. In January 2013 we established 359 plots of 10 m2 on a fragment of grassland in Sergipe, Brazil. In the same study area 25 colonies were randomly selected and the distance of the closest neighbor colony was determined. In total, 153 ant mounds were sampled (plots) and the density was estimated in 975 × colonies ha-1. Colonies were clumped in the environment either by plot sampling (χ2 = 453.93; p < 0.05) as well as by the method of nearest neighbor (Ax= 0.67, t = -1.72, p < 0.05). The aggregation of A. balzani colonies found in this study may be due to habitat heterogeneity or relate to the strategy of colony foundation. We conclude that the use of the nearest neighbor method was as accurate as the plot sampling method, providing the same results with much lower sampling effort

    Termite assemblages in dry tropical forests of Northeastern Brazil: Are termites bioindicators of environmental disturbances?

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    Termites exhibit several characteristics that emphasize their potential as bioindicators of habitat quality appropriate to use in ecological monitoring, especially for the Caatinga biome, but little is known about this group in different vegetations of the semi-arid regions of Northeastern Brazil. The study was conducted in three areas under different levels of anthropogenic disturbance, in the High Backwoods of Sergipe State, aiming to verify whether the termite communities create different groups, associated with the conservation of the area, by analyzing richness, abundance, and composition. Twelve transects of 65 x 2 m were demarcated in each area, where each one consisted of five plots of 5 x 2 m, making it possible to collect termites in all potential nesting sites. Four trophic groups of termites were sampled: (I) wood-feeders, (II) soil-feeders, (III) soil/wood interface-feeders and (IV) litter foragers. As environmental variables, soil samples from each plot were collected for particle size analysis, moisture percentage, and soil pH determination. Overall, richness and abundance were significantly different in the three areas studied. Wood-feeders were the most dominant in number of species and number of encounters collected at all sites, whereas the composition of termites in each area, given the environmental disturbances, was distinct. The environmental variables reinforced that the areas are different in terms of their degree of conservation. The agreement between environmental variables and ecological data for species composition fortifies the potential of termites as biological indicators of habitat quality in areas of Caatinga, Northeastern Brazil.

    Global Overview of Environmental Enrichment Studies: What Has Been Done and Future Directions

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    (1) Background: Environmental enrichment (EE) is a management principle aimed at meeting the needs of animals under human care by identifying and providing essential environmental stimuli to contribute to the integrity of their psychological and physiological well-being. Studies on EE have been carried out worldwide, but consolidated information on how it has been used, who it has been used for, how it has been evaluated, and what gaps still exist in the subject is scarce in the scientific literature. This study assessed, employing a systematic review, the global scenario of research into EE in animals kept under human care over the last 17 years, answering the above-mentioned questions. (2) Methods: A search for EE papers was carried out in the Web of Science and Scopus databases from January 2005 to December 2021, resulting in 2002 articles from which information was extracted. (3) Results: Results showed an increase in the number of articles published on EE, especially in farms, but studies in laboratory environments continue to be more frequent. Mammals and birds are the most studied animal groups. Cognitive enrichment is the least utilised by researchers. The number of publications by researchers from countries in the southern hemisphere is low. (4) Conclusions: Although the technique of EE is being widely used, it is still focused on certain groups of animals in certain captive environments and carried out mainly in the northern hemisphere of the planet. Therefore, the gaps pointed out here need to be filled by future studies

    Factors Affecting Space Use by Wild Boars in High-Altitude Tropical Forests

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    The wild boar (Sus scrofa Linnaeus, 1758) is considered one of the 100 worst invasive species in the world and is present in the high-elevation forests in Brazil. Our objective was to understand how landscape and atmospheric conditions affect space use by wild boars. We hypothesized that wild boars would be more frequent at lower elevations, warmer and wetter forested areas, and away from human disturbances. After three years of data collection (2013–2016) using 16 camera traps, 881 independent records were obtained with a mean of 4.44 ± 9.25 pigs per record. Wild boar frequency of occurrence was higher at lower elevations, in more humid and warmer areas, and farther away human disturbance factors, corroborating our initial hypothesis. Understanding space-use patterns of wild boars is necessary for the design of management strategies that target areas of more intense usage, as well as for defining more effective population-control techniques.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    The Impact of <i>Constrictotermes cyphergaster</i> (Termitidae: Nasutitermitinae) Termites on Semiarid Ecosystems in Brazil: A Review of Current Research

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    Termites have global distributions and play important roles in most ecosystems, often with high nest densities and interesting associations with other organisms. Constrictotermes cyphergaster, is a termite endemic to South America, widely distributed and very conspicuous, and has therefore been considered a good model for filling in gaps in general termite ecology and their relationships with other organisms (e.g., termitophily). A systematic review (content and bibliometric analyses) was used to gather all published scientific knowledge related to C. cyphergaster as well as to observe trends, verify gaps, and direct new perspectives for future studies of this species. We identified 54 studies, of which more than 50% were published in the last five years (28 articles). The majority of the articles investigated the relationships between C. cyphergaster and macroorganisms (44.4%), followed by specific aspects of its biology (25.9%). The collaboration network revealed that links between researchers are still limited and modular, but trending topics have changed over time. Additionally, there are differences in the aims of the studies being carried out in the Caatinga and Cerrado domains, with some information focusing only on one of those environments. Our results show that some gaps in the biology and ecology of C. cyphergaster remain to be explored, although collaborative efforts between researchers open opportunities for suggesting future studies that would make relevant contributions to the general knowledge of termites
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