Spatio-temporal variation of the pink shrimp Farfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae) associated to the seasonal overture of the sandbar in a subtropical lagoon

Abstract

ABSTRACT. On the southern Brazilian coast, the penaeid pink shrimp Farfantepenaeus paulensis (Pérez-Farfante, 1967) is intensively captured by both artisanal and industrial fisheries. In the Ibiraquera Lagoon, artisanal fishing of juvenile stocks has declined sharply over the last 15 years. The traditional management methods used by fishermen are no longer sustainable due to conflicts with the demands of tourism and weak environmental and public agencies. The dynamics of the timing of the artificial opening and natural reformation of a sandbar across the mouth of the lagoon are regarded as a central socio-ecological problem. We evaluated the abundance and biomass variation of F. paulensis throughout the year and along a spatial gradient measured from the sandbar into the lagoon. We also explored the influence of opening the sandbar on the shrimp population. Samples were collected monthly from February 2004 to February 2005, using a 27 mm mesh cast net, in four different areas, with three sites being sampled per area. Small numbers of large shrimps were captured in the upper area, while greater biomass and abundance of small shrimps were observed near the sandbar, suggesting the role of the inner area as a refuge for growing. The highest records for biomass and abundance were recorded during warm months, regardless if the lagoon was open or closed by the sandbar. The Ibiraquera Lagoon could be more productive for fishermen if the sandbar opening was coincident to the period of natural post-larvae influx. Furthermore, coastal stocks could be improved by opening the sandbar again during summer in conjunction with fishing quotas. KEYWORDS.Farfantepenaeus paulensis, coastal lagoon, artisanal fishery, Brazil. RESUMO. Variação espaço-temporal do camarão rosaFarfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae) associado à abertura sazonal da barra de conexão com o mar em uma lagoa subtropical. O camarão rosa Farfantepenaeus paulensis (Pérez-Farfante, 1967) é intensivamente capturado, tanto pela frota pesqueira industrial quanto artesanal na costa sul brasileira. Na Lagoa de Ibiraquera (SC), a captura artesanal de camarões tem diminuído gradativamente nos últimos 15 anos. Os métodos de gestão tradicionais utilizados pelos pescadores não são mais eficientes devido aos conflitos com o turismo e a gestão pública e ambiental. A dinâmica de abertura artificial e reestruturação natural do banco de areia no canal de contato da lagoa com o mar é considerada um problema socio-ecológico central no local. Neste estudo foi avaliada a variação na biomassa e abundância do F. paulensis ao longo do ano e em um gradiente espacial a partir do canal da barra e até o interior da lagoa. Foram realizadas coletas mensais de fevereiro de 2004 a fevereiro de 2005 com tarrafa de 27 mm de malha nas quatro lagoas que compõe a Lagoa de Ibiraquera, em três pontos em cada lagoa. Um número pequeno de grandes camarões foi significativamente (p < 0,05) capturado na área mais interna da lagoa, enquanto que maior biomassa e abundância de pequenos cam...

Before–after environmental impact assessment of an artificial channel opening on a south‐western Atlantic choked lagoon system

“…Environmental factors such as temperature, habitat type and salinity may be responsible for shaping community structure, especially in transitional habitats such as costal lagoons (Ramos‐Miranda et al ., ; Castillo‐Rivera et al ., ; Contente et al ., ). Several studies have evaluated the consequences of such factors on fish and crustacean communities in intermittently open lagoons (Saad et al ., ; Young & Potter, ; França et al ., ) and environments subjected to human interventions (Franco et al ., ; Ferreira & Freire, ; Verdiell‐Cubedo et al ., ). Nevertheless, the present study was the first to analyse the relationship between changes in the fish and crustacean assemblage structure associated with a human induced environmental change, represented here by the opening of a sea communication channel into a permanently choked lagoon.…”

“…The present study demonstrated that, at the time scale examined, the opening of the Tibau Channel in Piratininga Lagoon channel did not improve ecosystem processes or its fishing capacity, but caused losses in species richness, biomass and diversity. Different patterns have been found in other studies, which suggest that the connection with the sea may benefit the community by increasing larval and juvenile recruitment, and enable estuarine dependent species to complete their reproductive life cycle (Bell et al ., ; Saad et al ., ; Ferreira & Freire, ). These studies, however, often focus on systems adjusted to frequent sea isolation and communication periods.…”

“…Marine ecosystems are threatened by a suite of anthropogenic stressors, and transitional waters are particularly impacted by conflicting human activities (Halpern et al ., ; Vasconcelos et al ., ), which impact ecological functions, such as the maintenance of spawning, nursery and feeding areas for fish and crustacean species (Ferreira & Freire, ; Vasconcelos et al ., ; Ribeiro et al ., ), and biodiversity (Griffiths, ). Their high productivity underscore the need for assessing human impacts and environmental factors that may influence fish and crustacean communities in coastal areas (Vasconcelos et al ., ), estuaries (Barletta et al ., ; Castillo‐Rivera et al ., ; Contente et al ., ) and coastal lagoons (Akin et al ., ; Sánchez‐Botero et al ., ).…”

Long-Term Changes in Sanitary Conditions and Zooplankton Community in the Imboassica Lagoon (Rio De Janeiro, Brazil): Effects of Sandbar Openings

“…These transitional ecosystems with high biodiversity (López-Herrera et al 2021) play a critical role to regulate water flow, nutrient fluxes, and organisms from land and inland waters to the ocean (Newton et al 2014). The main environmental ecosystem services of coastal lagoons include water uses, ecological habitat for numerous commercial species, life quality, and income derived from services, such as tourism and recreation (Anthony et al 2009, Ferreira & Freire 2009, Despite ecological services and uses, human activities in the watershed have resulted in filling up (Millennium Ecosystem Assessment 2005), and nutrient enrichment (Rabalais et al 2009) by deforestation, fertilizers, urban sprawl, and aquaculture (Pérez-Ruzafa et al 2011, García & Muñoz-Vera 2015, especially in developing countries (Fauzi et al 2014). Such conditions promote coastal eutrophication (Middelburg & Levin 2009), one of the most common global change in the last decades (Diaz & Rosenberg 2008), which has resulted in harmful consequences associated with the ecological and sanitary degradation of lagoon waters.…”

Distribution and abundance of post-larvae and juvenile pink shrimpFarfantepenaeus paulensis(Pérez Farfante, 1967) in a subtropical estuary

“…However, in the Brazilian estuaries, there is little information on the preference of the post-larvae of pink shrimp. Previous studies mainly analysed juvenile populations and concluded that their abundance varies with season and that they prefer salinity levels between 15 and 30 (D'Incao, 1991; Branco & Verani, 1998; Costa et al ., 2008; Lüchmann et al ., 2008; Ferreira & Freire, 2009; Noleto-Filho et al ., 2017). D'Incao (1991) first studied the distribution of juveniles of pink shrimp in the Lagoa dos Patos estuary and highlighted the importance of protected shallow inlets for their growth, even without a quantitative analysis.…”