%0 Journal Article
%T Functional trophic composition of the ichthyofauna of forest streams in eastern Brazilian Amazon
%A Gabriel Louren£¿o Brej£¿o
%A Pedro Gerhard
%A Jansen Zuanon
%J Neotropical Ichthyology
%D 2013
%I Sociedade Brasileira de Ictiologia
%X This study aimed to describe the functional organization of the ichthyofauna of forest streams from northeastern Par¨¢ State, Brazil, based on behavioral observation of species' feeding tactics. Seven streams were sampled between June and November, 2010, during snorkeling sessions, totaling 91h 51min of visual censuses at day, dusk, and night periods. Seventy three species distributed in six orders, 26 families and 63 genera were observed, with dominance of Characiformes, followed by Siluriformes. From information gathered by ad libitum observations, each species was included in one of 18 functional trophic groups (FTGs), according to two main characteristics: (1) its most frequently observed feeding tactic; and (2) its spatial distribution in the stream environment, considering their horizontal (margins or main channel) and vertical (water column) dimensions. The most frequent FTGs observed were Nocturnal invertebrate pickers (9 species), Diurnal channel drift feeders (8 spp.), Diurnal surface pickers (7 spp.), and Ambush and stalking predators (6 spp.). The FTGs herein defined enable a comparative analysis of the structure and composition of ichthyofauna in different basins and environmental conditions, which presents an alternative approach to the use of taxonomic structure in ecological studies. The ichthyofauna classification based in FTGs proposed in this study is compared to three other classifications, proposed by Sazima (1986), Sabino & Zuanon (1998) and Casatti et al. (2001). Este estudo teve como objetivo descrever a organiza  o funcional da fauna de peixes de riachos do nordeste do estado do Par¨¢, Brasil, com base em observa  es comportamentais das t¨¢ticas alimentares das esp¨¦cies. Sete igarap¨¦s foram amostrados entre junho e novembro de 2010 por t¨¦cnicas de observa  es diretas durante sess es de mergulho livre, totalizando 91h 51min de observa  o, nos per¨ªodos diurno, crepuscular vespertino e noturno. Foram observadas 73 esp¨¦cies distribu¨ªdas em seis ordens, 26 fam¨ªlias e 63 g¨ºneros, com predom¨ªnio de Characiformes, seguidos por Siluriformes. A partir de informa  es coligidas por observa  es ad libitum, as esp¨¦cies foram organizadas em 18 grupos tr¨®ficos funcionais (GTFs), de acordo com duas caracter¨ªsticas principais: (1) a t¨¢tica alimentar observada com maior frequ¨ºncia; e (2) sua distribui  o espacial no riacho, considerando suas dimens es lateral (margens e canal central) e vertical (coluna d'¨¢gua). Os GTFs mais frequentes foram Catadores noturnos de invertebrados (9 esp¨¦cies), Coletores diurnos de canal (8 spp.), Catadores diurnos de su
%K Feeding tactics
%K Natural history
%K Snorkeling
%U http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013005000613