Dissertação
Análise da alimentação de Acestrorhynchus pantaneiro (Characiformes: acestrorhynchidae) em Três Rios do Rio Grande do Sul
Fecha
2012-02-29Registro en:
ZANINI, Lucéle Gonçalves. ANÁLISE DA ALIMENTAÇÃO DE ACESTRORHYNCHUS
PANTANEIRO (CHARACIFORMES: ACESTRORHYNCHIDAE) EM
TRÊS RIOS DO RIO GRANDE DO SUL. 2012. 70 f. Dissertação (Mestrado em Ciencias Biológicas) - Universidade Federal de Santa Maria, Santa Maria, 2012.
Autor
Zanini, Lucéle Gonçalves
Institución
Resumen
To understand the behavior of a species under the reproduction aspects, growth, birth rate,
mortality and migration is indispensable the knowledge of his alimentary behavior, still more
if treating of fishes with habit alimentary piscivorous that they occupy the top of the trophic
chain exercising a fundamental paper in the communities' structuring. This study had for
objectives to analyze the feeding of the fish-dog, Acestrorhynchus pantaneiro in three rivers
of Rio Grande do Sul, verifying which prey of larger preference and analyzing the
relationship of the size of the prey x predator, and for Rio Vacacaí and Rio dos Sinos the
group is considered allochthonous for the system. It was analyzed 380 examplaries captured
bimonthly among the years of 2010 and 2011 for Rio Jaguari, which presented the index of
vacuity of 0,74. In the rivers Vacacaí end of the Sinos 225 examplaries were analyzed, being
107 to Rio Vacacaí, captured in five points in the four seasons, presenting an index of vacuity
of 0,62 and 118 examplaries captured to Rio dos Sinos in the summer and autumn of 2011,
presenting result of IV of 0,41. In Rio Jaguari, differences were not verified between
atmosphere lentic and lotic, regarding the capture, the bimonth with higher temperatures
presented larger number of captured examplaries, and the studied species presented larger
alimentary activity at dusk and at night to Rio Jaguari and at night for in the rivers Vacacaí
end oh the Sinos. Through the analysis of the size of the prey x predator it could be verified
for the three rivers studied that prey larger they are ingested by predators also larger. The diet
of the species came fish-eating essentially feeding preferentially of small characins feeds.
Studies of the alimentary behavior of species fish-eating are necessary, overcoat of species
allochthonous, seeking to understand the relationships of those species as predators of chain
top in aquatic atmospheres, controlling the feeds populations.