No abstract

The establishment of an invasive species depends on reproductive success and dispersion capability in the new environment. One of the striking examples of invasion in urban environments is the mosquito Aedes aegypti Linnaeus, 1762 (Culicidae). The success of this species is primarily attributed to its ability to colonize urban environments, and some of the important adaptive strategies associated with this ability is the preference for humans as a blood source and intense occupation of residential (indoor) environments. This study evaluated the effects of location (indoor vs. outdoor) and water nutrient level (% organic matter) on the oviposition preference of A. aegypti in an urban environment. We used oviposition choice experiments to evaluate mosquito oviposition in containers holding 1:1 vs 1:0 ratios of water: organic matter placed indoors and outdoors. Eggs were sampled once per week for nine weeks. Our results revealed a strong oviposition preference for outdoor containers, with a significant preference for containers with higher concentrations of organic matter during the fifth to ninth weeks. However, mosquitoes occupying indoor environments did not prefer to lay eggs in containers with lower levels of organic matter. A better understanding of the preferences of A. aegypti regarding the nutrient level and location of oviposition containers can increase our understanding of the behavioral factors allowing mosquitoes to utilize anthropogenic environments.

No abstract

Natural lentic microhabitats are important for aquatic invertebrate communities in subtropical aquatic systems, which are usually dominated by mosquitoes, predators and zooplankton. Subtropical lentic microhabitats might be strongly affected by top-down effects of predators. We evaluated the predator effects on aquatic macroinvertebrate and zooplankton communities by using black plastic buckets (10 L) to simulate lentic microhabitats, which were divided into four treatments: predator absence and presence, and initial (on experiment start) and final (on experiment end) community controls. Large top predators (Odonata) had a stronger effect on community structure by their sit-and-wait predatory behaviour. The richness of total macroinvertebrates, Culex genus (most abundant organism), and zooplankton was highest in predators' absence. On the other hand, the sit-and-wait behaviour increased the density of organisms by selective predation on macroinvertebrates that feed in the bottom of the system. Also, the sit-and-wait behaviour increased the density of gathering and filtering collectors (top swimmers) by differences in space preference. We observed a positive species-specific relationship between Culex and predators. We concluded that predators' presence contributes to the balance of lentic microhabitat in subtropical lentic microhabitats by top-down control.

A escola tem papel fundamental na divulgação científica do conhecimento sobre as espécies, principalmente nas disciplinas de Ciências e Biologia e através da inserção de ações de educação ambiental. Para que estas ações sejam efetivas é fundamental perceber como os indivíduos conhecem e percebem o mundo natural que os rodeia. Visando entender se o contato com a natureza interfere no conhecimento de estudantes, investigamos o conhecimento dos mesmos sobre a espécie Amazona vinacea (papagaio-de-peito-roxo). Aplicamos um questionário para 63 estudantes do 9° ano do ensino fundamental, avaliamos o ambiente escolar e questionamos as professoras de ciências sobre suas aulas na natureza. O contato mais frequente com a natureza influenciou o conhecimento sobre a espécie. Diante disso, ressaltamos a importância de identificar o conhecimento prévio dos estudantes antes de serem trabalhadas ações na educação ambiental.