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Psitacídeos que vivem em cidades podem utilizar as praças urbanas como áreas para reprodução, refúgio ou alimentação. No entanto, existe pouco conhecimento sobre a dieta dessas aves nestes ambientes. Assim, este trabalho teve como objetivos identificar os recursos alimentares explorados por psitacídeos em praças urbanas e verificar as estratégias de forrageamento utilizadas. Foram visitados 10 praças urbanas da cidade de Uberlândia, MG, Brasil, no período de maio a dezembro de 2011. As aves foram investigadas pelos métodos animal-focal e ad libitum. As observações foram realizadas pela manhã e no final da tarde, totalizando 480 h de esforço amostral. Foram registrados 278 eventos de alimentação de quatro espécies de psitacídeos: Eupsittula aurea, Psittacara leucophthalmus, Brotogeris chiriri e Diopsittaca nobilis. As aves observadas consumiram recursos alimentares de 33 espécies vegetais, incluindo frutos (somente polpa, polpa junto com semente ou somente semente), flores, néctar e folhas. As famílias de plantas mais exploradas foram Fabaceae, Bignoniaceae e Arecaceae. A dieta dos psitacídeos foi bastante diversificada, com a exploração de uma ampla gama de espécies vegetais, principalmente as exóticas. Isso evidencia a importância das praças urbanas na alimentação, permanência e conservação de algumas espécies de psitacídeos nos centros urbanos.

It is known that pesticides such as abamectin (ABA) present cytotoxic effects on target organisms; however, the effects from ABA on non-target organisms such as amphibians are poorly understood. The aim of the current study is to investigate whether the exposure of Lithobates catesbeianus tadpoles to different abamectin concentrations [12.5, 25, and 50% of the median lethal concentration (LC)] leads to behavioral and morphological changes and/or generates possible cytotoxic effects. The aggregation test showed that tadpoles exposed to the highest ABA concentrations did not respond to the stimulus from non-familial and unrelated co-specific species. On the other hand, there was no difference in the total number of crossings in the central line of the herein adopted apparatus between groups; it suggests that ABA did not affect animal locomotion in the aforementioned test, although changes in the normal swimming pattern of tadpoles exposed to the pesticide were recorded in the swimming activity test. In addition, the herein exposed animals did not respond to the predatory stimulus in the antipredator response test; this result suggests defensive response deficit caused by the pesticide. With respect to their oral morphology, tadpoles exposed to ABA presented the lowest scores for mandibular pigmentation and structures, as well as for dentition condition. Finally, it was possible seeing that the exposure to ABA, even at the lowest concentration (12.5% of the LC), resulted in nuclear changes in the erythrocytes of the animals; these changes became evident in the increased number of micronuclei and in other nuclear abnormalities. Thus, besides confirming the cytotoxic potential of ABA in amphibians, the current study corroborates the hypothesis that the exposure to the herein investigated pesticide leads to behavioral and morphological changes in tadpoles, fact that may negatively reflect on the survival, as well as on natural populations of these individuals.

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