Biological competition between Biomphalaria glabrata (Say, 1818) and Biomphalaria tenagophila (d'Orbigny, 1835), observed in their natural breeding sites in Ourinhos, SP (Brazil)

• Autor(a) principal: Kawazoe, Urara
• Data de Publicação: 1980
• Outros Autores: Magalhães, Luiz Augusto, Hotta, Luiz Koodi, Takaku, Luiz
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Revista de Saúde Pública
• Texto Completo: https://www.revistas.usp.br/rsp/article/view/22983
• topic: Biomphalaria glabrata^i1^sbiolo; Biomphalaria tenagophila^i1^sbiolo; Biomphalaria glabrata^i2^sbiol; Biomphalaria tenagophila^i2^sbiol

Possible competition between Biomphalaria glabrata and Biomphalaria tenagophila were observed at three natural breeding sites in Ourinhos (SP) between November 27, 1973 and February 20, 1979. The snails were collected every three months until 1976; after this period they were every six months. A total of B. tenagophila 5,249 snails and 353 B. glabrata were collected at the first study site (irrigation ditch); at the second environment 1,703 B. tenagophila and 64 B. glabrata were collected, in the third environment 1,249 B. tenagophila and 4 B. glabrata were collected. Only the data from the first freshwater environment furnished information relating to the displacement of B. glabrata and B. tenaglophila. Statistical analysis suggested competition between the two species with a tendency for B. glabrata to be excluded. It seems that the displacement took place over a period of at least five years. Although the evidence for competitive displacement between B. glabrata and B. tenagophila is clear, we were not able to determine the exact mechanism for this phenomenon.