Spatial and temporal distribution of fish eggs and larvae in a subtropical coastal lagoon, Santa Catarina State, Brazil

Abstract

This study investigated the variation in abundance, distribution and composition of ichthyoplankton in a lagoon in southern Brazil through the year and at different stations within the lagoon. Ibiraquera Lagoon is a shallow coastal lagoon connected to the sea by a semi-permanent sandbar. Ichthyoplankton samples were collected monthly from December 2003 to December 2004, with a 200 µm mesh net using horizontal surface hauls. A colder, drier period was detected, contrasting with warm months during which salinity varied depending on rainfall and whether the sandbar was open or closed. The mean abundance of ichthyoplankton over the study period was 459.6 ± 76.2 (SE) eggs · 100 m -3 and 63.6 ± 7.9 (SE) larvae · 100 m -3 , and they were present during all months. Significantly higher abundances of eggs and larvae were observed during warm months. The community was dominated by the family Engraulidae followed by Clupeidae, Gobiidae and Mugilidae. Engraulidae and Clupeidae were present throughout the year, with greater abundances in months with higher temperatures. Some coastal fish species spawn in Ibiraquera Lagoon, mainly near to the sandbar, demonstrating that the lagoon is a spawning area for coastal stock. We recommend the establishment of environmental procedures to promote the conservation of Ibiraquera Lagoon and its ichthyoplankton community.A abundância, distribuição e composição do ictioplâncton foram investigadas em uma lagoa no sul do Brasil durante um ano e em diferentes estações dentro da lagoa. A lagoa de Ibiraquera é uma lagoa costeira rasa, conectada ao mar através de uma barra semi-permanente. As amostras de ictioplâncton foram coletadas mensalmente entre dezembro de 2003 e dezembro de 2004, com uma rede cônico-cilíndrica de 200 µm de malha em arrastos horizontais e de superfície. Foi detectado um período frio e seco em contraste aos meses quentes e com variação na salinidade em função das chuvas e da barra estar aberta ou fechada. A abundância média do ictioplâncton, durante o período de estudo, foi de 459,6 ± 76,2 (SE) ovos · 100 m -3 e 63,6 ± 7,9 (SE) larvas · 100 m -3 , e ocorreram em todos os meses. As abundâncias de ovos e larvas foram significativamente maiores nos meses quentes. A comunidade foi dominada pela família Engraulidae seguida pelas famílias Clupeidae, Gobiidae e Mugilidae. As famílias Engraulidae e Clupeidae ocorreram principalmente nos meses com maiores temperaturas. Alguns peixes costeiros desovam dentro da lagoa, principalmente próximo a barra, evidenciando que a lagoa é uma área de desova para o estoque costeiro. Recomenda-se o estabelecimento de ações ambientais que promovam a conservação da lagoa de Ibiraquera e da comunidade ictioplanctônica.

Structure and diversity of fishes in a freshwater and coastal subtropical lagoon

“…The greater abundance of eggs and larvae collected in Peri Lagoon occurred in seasons with lower temperature (autumn or winter), unlike other studies at subtropical sites such as Babitonga Bay (Costa et al ., ), Ibiraquera Lagoon (Macedo‐Soares et al ., ) and Patos Lagoon (Muelbert & Weiss, ) where the highest abundances were in spring and summer.…”

“…On the other hand, engraulids and clupeids have planktonic life cycles (Mai & Vieira, 2013) and were the dominant groups (>35% of abundance) of larvae collected in the lagoon, with P. platana (Clupeidae) the dominant species. The dominance of Engraulidae and Clupeidae in fish larvae data is common in the coastal environments of north-east (Mafalda et al, 2008), south-east (Joyeux et al, 2004;Castro et al, 2005;Chagas et al, 2006) and south Brazil (Barreiros et al, 2009;Macedo-Soares et al, 2009) and is related to their life cycles.…”

Large-Scale Ichthyoplankton and Water Mass Distribution along the South Brazil Shelf

“…and Engraulidae eggs, are expected near or in front of large estuaries because of the contribution of estuarine spawners and estuarine-dependent fishes that use these environments for reproduction and/or as nursery areas [70] – [72] . Even small coastal lagoons can contribute to high quantities of fish eggs and larvae and increase ichthyoplankton abundance in coastal waters [73] . Continental runoff and tidal cycles associated with wind stress transport fish eggs and larvae to coastal waters [74] and increase their abundance in adjacent regions.…”

A preliminary assessment of larval fish assemblages on artificial reefs in the nearshore Southern Brazil

“…It is important to note that the highlighted results refer exclusively to the summer period. Therefore, it should not be assumed that ichthyoplankton (richness and abundance) are temporally stable since several other studies have shown a clear temporal variability (Nonaka et al, 2000;Castro et al, 2005;Macedo-Soares et al, 2009).…”