Prey selectivity of the octocoral Carijoa riisei at Pernambuco, Brazil
subject: Alcyonacea, Trophic ecology, alimentação natural, disponibilidade de presas, ecología trófica, natural feeding, prey availability, prey selectivity, seletividade de presas
description: This study was designed to evaluate prey selection (type and size) by the octocoral Carijoa riisei at Porto de Galinhas beach, Northeast Brazil, relating prey availability in plankton with the content inside polyps. Diatoms and cyanophytes were the predominant items found in both polyp gastric cavity and plankton. A correlation between prey abundance in the plankton and in the gastric cavity of C. riisei polyps was observed. Mastogloia sp. showed the highest positive electivity index (0.99). Benthonic items were found, with 0.51% of total consumed preys. The size amplitude of prey items in the plankton was similar to those found inside the polyps, although the mean prey size in the polyps (112.7 µm) was significantly lower than the value found in the plankton (240.5 µm). Thus, the study indicates some size selectivity in this species or at least size limitation. From the results, we concluded that the octocoral C. riisei is an opportunistic polyphagous species in the Brazilian northeast coast, showing suspensivorous passive filtering feeding habit with a preference for small prey items and evidencing its important ecological role in the reefal ecosystem as responsible for bidirectional energy transference between pelagic zones and the benthos.Este estudo foi desenvolvido para avaliar a seletividade de presas (tipo e tamanho) do octocoral Carijoa riisei na praia de Porto de Galinhas, nordeste do Brasil, relacionando a disponibilidade de presas no plâncton com o conteúdo gástrico dos pólipos. Diatomáceas e Cianofíceas foram os itens de presas mais abundantes tanto na cavidade gástrica dos pólipos quanto no plâncton. Foi observada uma correlação entre a abundância de presas no plâncton e na cavidade gástrica dos pólipos de C. riisei. Mastogloia sp. apresentou o maior índice de seletividade positiva (0,99). Foram encontrados organismos bentônicos, totalizando 0,51% do total de presas consumidas. A amplitude de tamanho das presas no plâncton foi similar à da cavidade gás…
creator: Paula B. Gomes, Ana K.F. Lira, Jean-Philippe Naud, Andre M. Santos, Carlos D. Pérez
source: Anais da Academia Brasileira de Ciências
publisher: Academia Brasileira de Ciências
date: 2012
relation: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000100016
coverage: Science