Tidal influence on surf zone ichthyofauna structure at three sandy beaches, southeastern Brazil

Abstract

Natural assemblages show large variability at multiple scales in space and time as a consequence of several abiotic and biotic factors. This study was conducted in the surf zone of Arraial do Cabo (22º 58'S, 42º 01'W) and tested the hypothesis that the ichthyofauna composition and structure differ according to the tidal variation at three beaches with different morphodynamic characteristics. From September 2001 to August 2002 three monthly hauls were carried out at each beach during high (N = 6) and low tide (N = 6) with a beach seine (25 m length, 2,50 m height, 10 mm mesh). At Praia Grande and Prainha beaches, the number of species and individuals was higher during low tide. Also, CPUE (grams) at Praia Grande and Prainha was higher during high tide indicating a movement of many benthivore and piscivore species into the intertidal zone, due to the greater food availability. The fish community structure differed between Prainha and Praia Grande according to the tide in relation to fish biomass, which was higher at high tide, except for Praia dos Anjos (low tide) partially supporting the initial hypotheses. However, the number of individuals and species richness and diversity were higher during low tide, different from the proposed statement, as a reflex of juvenile individuals' abundance.<br>Comunidades de peixes sofrem grande variabilidade em escala espacial e temporal em conseqüência de vários fatores abióticos e bióticos. Este estudo foi realizado na zona de arrebentação em Arraial do Cabo (22º 58'S, 42º 01'W) e testada a hipótese de que a composição e a estrutura da ictiofauna difere de acordo com a variação de maré em três praias com características morfodinâmicas distintas. De setembro/2001 a agosto/2002 foram realizados três arrastos mensais em três pontos de cada praia nos períodos de maré baixa (N = 6) e alta (N = 6), através de uma rede do tipo picaré (beach seine) com 25 m de comprimento por 2,50 m de altura e malha de 10 mm. Na Praia Grande e Prainha, o número de espécies e indivíduos foi superior em maré baixa. Já a CPUE (grama) na Praia Grande e Prainha foi superior na maré alta, indicando um movimento de muitas espécies bentívoras e piscívoras para a zona entremarés em maré cheias, devido à maior disponibilidade de alimento. A estrutura da comunidade de peixes na zona de arrebentação, Praia Grande e Prainha diferiu em função da maré com relação à biomassa de peixes capturados, superior no período de maré alta, exceto na Praia dos Anjos (maré baixa) confirmando parcialmente a hipótese inicial. Já o número de indivíduos, a riqueza e a diversidade de espécies foi superior na maré baixa, diferente do proposto, reflexo da grande abundância de indivíduos juvenis

Temporal patterns in the intertidal faunal community at the mouth of a tropical estuary

“…On the other hand, Morrison et al . () and Gaelzer & Zalmon () found more species during the low tide. Similar assemblages of fishes (at species level) were detected in this study and those of Pessanha & Araújo (), Souza‐Conceição et al .…”

“…Studies using beach seines in sandy beaches along the Brazilian coast (Pessanha & Araújo, ; Gaelzer & Zalmon, ; Lima & Vieira, ; Souza‐Conceição et al ., ; Oliveira & Pessanha, ), Europe (Santos & Nash, ; Beyst et al ., ; Selleslagh & Amara, ), southern Japan (Suda et al ., ; Inui et al ., ), northern Australia (Blaber et al ., ) and New Zealand (Morrison et al ., ) recorded varying numbers of fish species, density and biomass (Table ).…”

The effects of exposure in sandy beach surf zones on larval fishes

“…Sandy beach surf zones are typically dominated by a few species (Pearce et al, 1942;McFarland, 1961;Modde & Ross, 1981;Lasiak, 1983;Bennett, 1989;Gibson et al, 1996;Layman, 2000;Wilber et al, 2003;Gaelzer & Zalmon, 2008), specifically those dependent on estuaries in South Africa (Whitfield, 1989a;Cowley et al, 2001;Strydom, 2003). Results from this study indicate the importance of proximity to estuaries in structuring larval fish assemblages.…”

Thermal response of demersal and pelagic juvenile fishes from the surf zone during a heat‐wave simulation

“…Despite dynamic habitats with large and frequent thermal variations selects organisms with high thermal tolerance, they have limited acclimation plasticity (Fangue, Osborne, Todgham, & Schulte, ) and live closer to their thermal limits (Madeira et al, ). The pelagic fish from surf zone are susceptible to abrupt variations of abiotic factors (Araújo, Rosa, Fernandes, Ripoli, & Krohling, ; Giannini & Paiva‐Filho, ; Kingsford & Finn, ), such as diel variation in water temperature (Gaelzer & Zalmon, ), which usually present higher thermal tolerance but lower thermal plasticity.…”

“…(Feddersen, ; Feddersen & Trowbridge, ; Ruessink, ). In the surf zone of southeastern Brazil, the water mean temperature ranged on the order of 10°C, with higher values during the summer months and lower values in the winter, influencing the community composition and abundance of Neotropical fishes (Gaelzer & Zalmon, , ; Gondolo, Mattox, & Cunningham, ). In order to investigate how heat‐waves can affect the different Neotropical juvenile fish species with different life habitats, we determined the upper thermal tolerance (CT max ) of two demersal and two pelagic fish species before and after a “heat‐wave experiment” (14 days at +5°C).…”