Frugivory and seed dispersal of Miconia theaezans (Bonpl.) Cogniaux (Melastomataceae) by birds in a transition palm swamp: gallery forest in Central Brazil

Abstract

The objective of this study was to evaluate potential avian dispersers of Miconia theaezans by dietary habits in the Cerrado of Central Brazil. Forty-two hours and 40 minutes of focal tree observation were conducted between 7:00 AM and 5:00 PM. For each bird species that consumed the fruit, we registered: the time they remained on the plant, the total amount of fruit they consumed, foraging tactics and strategies to consume the fruit. Five-hundred and fifty-nine units of fruit were consumed in 47 visits by seven bird species. Thraupidae was the most frequent and representative family and Tangara cayana was the main consumer. The Tachyphonus rufus had the highest rate of intake of the entire fruit, however the rates were not significantly different among the visitors. The most-used foraging tactic by all species was to consume the fruit while "perched" (95.74% of the visits). The most commonly-used consumption strategy was to mandibulate the fruit and swallow all the contents (65.12%). Omnivores were the predominant visitors (71.43%) and made most of the visits (89.36%). All visiting species could act as potential dispersers of M. theaezans, which demonstrates the low selectiveness of this pioneer plant towards its frugivorous.Keywords: fruits, pioneer species, birds, cerrado. Frugivoria e dispersão de sementes de Miconia theaezans (Bonpl.) Cogniaux (Melastomataceae) por aves em uma transição Vereda -Mata de galeria no Brasil CentralResumo O objetivo deste trabalho foi avaliar, através do comportamento alimentar, as aves potencialmente dispersoras de Miconia theaezans no Cerrado do Brasil Central. Foram realizadas 42 horas e 40 minutos de observações árvore-focal, entre 07:00 e 17:00 horas. Foram registrados para cada espécie de ave consumidora de frutos: tempo de permanência na planta, total de frutos consumidos, tática de forrageio e estratégia de consumo dos frutos. Foram consumidos 559 frutos em 47 visitas, por sete espécies de aves. Thraupidae foi a família mais representativa e frequente e Tangara cayana foi o principal consumidor. A maior taxa de consumo de frutos inteiros foi encontrada para Tachyphonus rufus, porém não foi significativamente diferente entre os visitantes. A tática de forrageamento mais utilizada no consumo dos frutos de todas as espécies foi "empoleirado" (95,74% das visitas). A estratégia de consumo mais utilizada foi mandibular o fruto e engolir todo o conteúdo (65,12%). Houve predominância de onívoros em termos de visitantes (71,43%) e visitas (89,36%). Todas as espécies visitantes podem atuar como potenciais dispersoras de M. theaezans, demonstrando a baixa seletividade desta planta pioneira em relação aos seus frugívoros.Palavras-chave: frutos, espécies pioneiras, aves, cerrado.

Apomixis does not affect visitation to flowers of Melastomataceae, but pollen sterility does

“…Moreover, some apomictic species of Miconia are invasive in Old World areas, which means that their broad ranges may still be increasing (Meyer ; Baruch et al . ; Borges & Melo ). As found here, low pollen viability can have a negative impact on the availability of resources offered to pollinators.…”