ASPECTOS DA ALIMENTAÇÃO NATURAL DO CAÇÃOFRANGO Rhizoprionodon lalandii (VALENCIENNES,1841) (ELASMOBRANCHII, CARCHARHINIDAE) NO MUNICÍPIO DE BARRA VELHA, SANTA CATARINA.

Abstract

The brazilian sharpnose shark Rhizoprionodon lalandii (Valenciennes,1841) occurs in the east coast of South America, from Panama to Santa Catarina. The present work studied some aspects of the feeding behavior of R. lalandii. Samples were collected monthly, between September 1999 and June 2000 being captured by artisanal fleet. The alimentary items were identified to the lowest taxonomic level possible. The occurrence percentage of the items was obtained through the equation: n.o of stomachs that contained the item / n.o of stomachs that contained food x 100. From the 78 examined stomachs, 61 (78%) contained food. The predominant items in the stomachs were Teleostei, representing 47% of the total of items followed by Molusca: Cephalopoda (26%). Most of the bony fishes found in the stomachs content were Clupeiformes and all Cephalopoda represented by the suborder Myopsida. The largest repletion GR 4, most of the individuals presented stomachs filled less than GR 2 and GR 1, and some had empty stomachs (22%). R. lalandii, feeds mainly on pelagic species specially small bony fishes and squids. As the diversity of preys was small, it is supposed that R. lalandii is a selective predator.