Abundance and potential impact of granivorous birds on irrigated rice cultivation, Itajaí, Santa Catarina, Brazil

Abundância e potencial impacto das aves granívoras no cultivo de arroz em Itajaí, Santa Catarina, Brasil

Joaquim Olinto Branco Bruna Rafaela Keske Edison Barbieri About the authors


The assemblage of granivorous birds in the irrigated paddy-fields was evaluated over an annual cultivation cycle by means of 12 monthly samplings undertaken in each of 3 areas (of a total of 90 ha) in Itajaí, Santa Catarina, between August 2010 and July 2011. Of a total of 10 species, distributed among 5 families and 2 orders, Sturnella superciliaris (43.88%) and Sicalis flaveola (36.88%) were the most abundant. The regular species contributed with 45.17%, followed by the occasional (30.37%) and the seasonal (24.43%). Only the abundance of S. flaveola presented significant differences between the months of sampling (F11-33 = 7.1290, p < 0.01) as a result of the lower values recorded in December and January. The diversity and evenness indices showed similar fluctuation, with mean values ranging between 0.47 ± 1.37 and 0.29 ± 0.83, respectively. The average losses per hectare, due to the action of S. superciliaris and S. flaveola , were 8.35 ± 1.66 and 6.10 ± 1.48 kg of rice, equivalent to R$ 49.07 in the 3 areas monitored, giving a total average annual loss of 82.9 kg for the 90 ha of rice monitored.

granivorous birds; Sturnella superciliaris; Sicalis flaveola; irrigated rice

Instituto Biológico Av. Conselheiro Rodrigues Alves, 1252 - Vila Mariana - São Paulo - SP, 04014-002 - São Paulo - SP - Brazil
E-mail: arquivos@biologico.sp.gov.br