Effect of Habitat Disturbance on Colony Productivity of the Social Wasp Mischocyttarus consimilis Zikán (Hymenoptera, Vespidae)

Social wasps are important elements of the fauna in a variety of environments, including human-modified environments. Evidence indicates that habitat quality affects the growth of  colonies of social wasps in urban environments. This study investigated whether the colony productivity of the social wasp Mischocyttarus consimilis Zikán (Hymenoptera, Vespidae) is affected by loss habitat quality in human-occupied environment. Nests of M. consimilis were collected in forest and urban environment between January 2010 and June 2011. Only nests that reached the decline stage were sampled. As productivity parameters, we measured the total number of cells constructed, total number of adults produced and dry mass of the nests. Productivity was significantly lower in urban than in forest environment for all parameters analyzed. Habitat quality is probably the principal factor that contributed to the lower productivity in urban environment. In this type of environment, particularly where the study was conducted, the vegetation adjacent to the nesting sites was composed predominantly of grasses. Such habitats may have limited resources available, especially those resources used by the wasps for feeding the immature, such as larvae of other insects. That result suggests that human degradation of habitats negatively affects the final productivity of colonies of social wasps

Spatial connectivity of aquatic macrophytes and flood cycle influence species richness of an ant community of a Brazilian floodplain

Despite the environmental and economic importance of Pantanal, there are few studies quantifying the influence of sazonality and spatial variation on biological diversity in this ecosystem. In this context, the present work aimed to study the assemblage of ants associated with macrophytes during the flood and dry period of Paraguay river, in marginal environments in the Pantanal of Porto Murtinho, Mato Grosso do Sul. We observed a wide variation in the temporal distribution of the diversity of the assemblages of ants, since from 37 species, 36 occurred in the dry and 20 in the flood period. Of the total of macrophyte species observed, in only 12.5% we found a more specific correlation with ants that were nesting in spaces provided by plants representing a total of 10.52% of the species analized.