Captive-born collared peccary (Pecari tajacu, Tayassuidae) fails to discriminate between predator and non-predator models

Captive animals may lose the ability to recognize their natural predators, making conservation programs more susceptible to failure if such animals are released into the wild. Collared peccaries are American tayassuids that are vulnerable to local extinction in certain areas, and conservation programs are being conducted. Captive-born peccaries are intended for release into the wild in Minas Gerais state, southeastern Brazil. In this study, we tested the ability of two groups of captive-born collared peccaries to recognize their predators and if they were habituated to humans. Recognition tests were performed using models of predators (canids and felids) and non-predators animals, as well as control objects, such as a plastic chair; a human was also presented to the peccaries, and tested as a separate stimulus. Anti-predator defensive responses such as fleeing and threatening displayswere not observed in response to predator models. Predator detection behaviors both from visual and olfactory cues were displayed, although they were not specifically targeted at predator models. These results indicate that collared peccaries were unable to recognize model predators. Habituation effects, particularly on anti-predator behaviors, were observed both with a 1-h model presentation and across testing days. Behavioral responses to humans did not differ from those to other models. Thus, if these animals were to be released into the wild, they should undergo anti-predator training sessions to enhance their chances of survival

Environmental severity promotes phylogenetic clustering in campo rupestre vegetation

The stress-dominance hypothesis postulates that the importance of competition in plant communities declines with increasing environmental stress while the importance of environmental filters increases. To test this hypothesis for campo rupestre vegetation, we analyzed phylogenetic diversity and community structure of angiosperm communities at two study sites within the Itacolomi State Park, Minas Gerais, Brazil. Plots representing more favorable habitats, such as those with a higher percentage of rocky outcrops that might permit the tapping of deeper water and nutrient resources as well as higher contents of clay and loam thereby increasing water and nutrient availability, show higher phylogenetic diversity and therefore lower phylogenetic clustering than plots with more sever habitats. This observation is consistent with the stress-dominance hypothesis if we assume ecological niches to be conserved within evolutionary niches. However, more comprehensive studies including tests for phylogenetic signal of ecological niches are necessary before generalizations for larger regions may be carried out

Riparian forest restoration as sources of biodiversity and ecosystem functions in anthropogenic landscapes

AbstractRestoration of tropical riparian forests is challenging, since these ecosystems are the most diverse, dynamic, and complex physical and biological terrestrial habitats. This study tested whether biodiversity can predict ecosystem functions in a human-impacted tropical riparian forest.We explored the effects of several biodiversity components (taxonomic or functional groups) on different ecosystem functions associated with restored riparian forestsOverall, 49% of the biodiversity components showed positive effects on ecosystem functions, each component to a different degree. In general, our results showed that both taxonomic and functional biodiversity had strong effects on ecosystem functions indicating that floral and faunal biodiversity enhanced the multifunctionality of these restored riparian tropical forests.These findings indicate that in restored riparian forests, recovery of biodiversity is followed by improvement in important ecosystem functions that are the basis for successful restoration. Future research and policy for restoration programs must focus on restoring elementary faunal and floral components of biodiversity in order to promote ecosystem multifunctionality.</jats:p

Propagation and establishment of rupestrian grassland grasses for restoration of degraded areas by mining

Investigations on the propagation and establishment of native grasses of rupestrian grassland on degraded substrates are essential to enable their use in the restoration of degraded areas, thus reducing the use of exotic species. This study aimed to evaluate the sexual and asexual propagation, establishment and growth of Axonopus laxiflorus (Trin.) Chase and Sporobolus metallicolus Longhi-Wagner & Boechat, two native grasses from rupestrian grassland developed on laterite substrate of an area degraded by bauxite mining. In greenhouse experiments, A. laxiflorus was propagated by tillers and S. metallicolus by seeds and tillers. Both species were also evaluated for germination in a germination chamber on the treatments: control, addition of potassium nitrate and heating at 80 ?C for 2 min. In these evaluations, success of S. metallicolus germination was between 77 and 90%, without significative difference among treatments, whereas A. laxiflorus did not germinate. In the laterite substrate, S. metallicolous, propagated by seeds, showed 29% of survival, whereas in the vegetative propagation all plants of the two species survived. Eight months after starting the tiller experiment, S. metallicolus and A. laxiflorus presented a biomass increase of 239 and 75%, respectively. Although A. laxiflorus showed root biomass approximately seven times higher than S. metallicolus, the two species presented similar root length, that is, S. metallicolus contained more fine roots. The results show that the species can efficiently propagate vegetatively and, in the case of S. metallicolus, sexually. The success of the species in a substrate poor in nutrients and rich in Al, Fe and Mn indicates that they can be used in the restoration of areas degraded by bauxite and iron mining, which are important mining activities in Brazil