A food interaction network between psittacines and plants in an urban area in the city of São Carlos - SP, southeastern Brazil.

The Psittacidae presents a great diversity of species in the Neotropical region performing fundamental ecological functions for ecosystems. These frugivorous birds can occupy different positions in the antagonistic-mutualistic gradient of food interactions, acting as predators and/or as seed dispersers. Little is known about bird-plant ecological interaction networks focusing on psittacines in urban environments, which may compromise the management of natural areas in anthropic landscapes and hinder the planning of conservation strategies. In this context, the present study aimed to analyze the network of feeding interactions between psittacines and plants that occur in green areas in urban and periurban areas of the municipality of São Carlos, São Paulo State, southeastern Brazil. Starting with an active searching added to the application of the focal animal sampling at 36 systematized sampling points during the years 2019, 2020 and 2021, the plant species consumed by parrots in the study area were observed. Four species of birds of the Psittacidae family were recorded consuming food resources from 46 plant species. The order of relevance of the birds in structuring the ecological network was: Brotogeris chiriri (Vieillot, 1851), Psittacara leucophthalmus (Statius Muller, 1872), Forpus xanthopterygius (Spix, 1843) and Eupsittula aurea (Gmelin, 1788). The most consumed plants were Syagrus romanzoffiana, Salix babylonica, Caesalpinea pluviosa, Mangifera indica and Handroanthus heptaphyllus. The pattern of consumption by birds was significantly different among species, and overall, they had a broad diet and medium niche overlap. Network nesting was low, as was connectance, i.e., the number of interactions or connections observed between pairs of species was considerably less than the total number possible. Network asymmetry was considerably high, with the psittacine group performing interactions with a large number of plant species, while each plant received on average few psittacine species. The results point to a high plasticity in the use of food resources in anthropic landscapes, indicating that the occupation of the urban environment by psittacines has been occurring successfully and may benefit the populations of the species recorded here.

A food interaction network between psittacines and plants in an urban area in the city of São Carlos - SP, southeastern Brazil / Uma rede de interação alimentar entre psitacídeos e plantas em uma área urbana na cidade de São Carlos - SP, sudeste do Brasil

Abstract The Psittacidae presents a great diversity of species in the Neotropical region performing fundamental ecological functions for ecosystems. These frugivorous birds can occupy different positions in the antagonistic-mutualistic gradient of food interactions, acting as predators and/or as seed dispersers. Little is known about bird-plant ecological interaction networks focusing on psittacines in urban environments, which may compromise the management of natural areas in anthropic landscapes and hinder the planning of conservation strategies. In this context, the present study aimed to analyze the network of feeding interactions between psittacines and plants that occur in green areas in urban and periurban areas of the municipality of São Carlos, São Paulo State, southeastern Brazil. Starting with an active searching added to the application of the focal animal sampling at 36 systematized sampling points during the years 2019, 2020 and 2021, the plant species consumed by parrots in the study area were observed. Four species of birds of the Psittacidae family were recorded consuming food resources from 46 plant species. The order of relevance of the birds in structuring the ecological network was: Brotogeris chiriri (Vieillot, 1851), Psittacara leucophthalmus (Statius Muller, 1872), Forpus xanthopterygius (Spix, 1843) and Eupsittula aurea (Gmelin, 1788). The most consumed plants were Syagrus romanzoffiana, Salix babylonica, Caesalpinea pluviosa, Mangifera indica and Handroanthus heptaphyllus. The pattern of consumption by birds was significantly different among species, and overall, they had a broad diet and medium niche overlap. Network nesting was low, as was connectance, i.e., the number of interactions or connections observed between pairs of species was considerably less than the total number possible. Network asymmetry was considerably high, with the psittacine group performing interactions with a large number of plant species, while each plant received on average few psittacine species. The results point to a high plasticity in the use of food resources in anthropic landscapes, indicating that the occupation of the urban environment by psittacines has been occurring successfully and may benefit the populations of the species recorded here.

Resumo A família Psittacidae apresenta grande diversidade de espécies na região Neotropical, as quais desempenham funções ecológicas fundamentais para os ecossistemas. Essas aves frugívoras podem ocupar diferentes posições no gradiente antagonista-mutualista de interações alimentares, atuando como predadoras e/ou como dispersoras de sementes. Pouco se sabe sobre redes de interações ecológicas ave-planta com foco nos psitacídeos em ambientes urbanos, o que pode comprometer a gestão de áreas naturais em paisagens antrópicas e dificultar o planejamento de estratégias de conservação. Nesse contexto, o presente estudo objetivou analisar a rede de interações alimentares entre psitacídeos e plantas que ocorrem em áreas verdes da zona urbana e periurbana do município de São Carlos, estado de São Paulo, sudeste do Brasil. A partir de busca ativa somada à aplicação do método animal-focal em 36 pontos de amostragem sistematizada de 2019 a 2021, foram observadas as espécies de plantas consumidas por psitacídeos na área de estudo. Foram registradas 4 espécies de Psittacidae consumindo recursos alimentares de 46 espécies de plantas. A ordem de relevância das aves na estruturação da rede ecológica foi: Brotogeris chiriri (Vieillot, 1851), Psittacara leucophthalmus (Statius Muller, 1872), Forpus xanthopterygius (Spix, 1843) e Eupsittula aurea (Gmelin, 1788). As plantas mais consumidas foram Syagrus romanzoffiana, Salix babylonica, Caesalpinea pluviosa, Mangifera indica e Handroanthus heptaphyllus. O padrão de consumo pelas aves foi significativamente distinto entre as espécies, sendo que no geral apresentaram uma dieta ampla e sobreposição de nicho mediana. O aninhamento da rede foi baixo, assim como conectância, ou seja, o número de interações ou conexões observadas entre pares de espécies foi consideravelmente menor do que o número total possível. A assimetria da rede foi consideravelmente alta, com o grupo dos psitacídeos realizando interações com um grande número de espécies de plantas, ao passo que cada planta recebeu em média poucas espécies de psitacídeos. Os resultados apontam para uma alta plasticidade no uso de recursos alimentares em paisagens antrópicas, indicando que a ocupação do ambiente urbano por psitacídeos vem ocorrendo com sucesso e pode beneficiar as populações das espécies aqui registradas.