EFFECTS OF INVASIVE SPECIES SNAILS IN CONTINENTAL AQUATIC BODIES OF PERNAMBUCANO SEMIARID

Paulo Souza Almeida, Silvano Lima Nascimento-Fillho, Fábia Segundo Viana

Resumo


The aim of this study was a survey of the species of shells and evaluate the effect of exotic species Melanoides tuberculata in reservoirs of Pajeú River Basin. Samples were collected with the aid of trawl with a mesh aperture of 5 mm and dip net with mesh size 2 mm. We identified a total of 60.244 exemplars, distributed among species Melanoides tuberculata (49,398), Pomacea lineata (573), Biomphalaria straminea (376) and Physa marmorata (01). In all reservoirs, M. tuberculata presented dominance and relative abundance higher than 85%. In Cachoeira II and Jazigo reservoirs from 2008 to 2009, P. lineata was classified as casual 8.20 and 2.98%, respectively, while for the Jazigo and Serrinha reservoirs in 2012, the species was classified as rare. The native specie P. marmorata was classified as rare 0.05%. With regard to frequency of occurrence, all species were classified as euconstantes (occurrence higher than 65%), except P. lineata and P. marmorata, captured in Jazigo reservoir in the period from May to November/12, which were classified as accessory (occurrence less than 40%). The greater density of was observed for M. tuberculata (1.636 individuals/m2) no Serrinha reservoir. Rainfall and water temperature did not influence the density and distribution of species (p < 0.05). The specie M. tuberculata showed strong adaptability to environmental conditions. In all reservoirs the high dominance this specie is probably the main cause for the low diversity indices and density of native snails. P. marmorata considered vulnerable to extinction stood out for its low density and frequency, becoming an important point to be investigated as a possible species harmed by the colonization of M. tuberculata.

Palavras-chave


Benthic community, Gastropods, bioinvasion, limnic environments



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Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial 4.0 Internacional.

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