Biologia do Camarão-Sete-Barbas, Xiphopenaeus kroyeri (Heller,1862)(Crustacea, Decapoda, Penaeidae) e aspectos da sua pesca na reserva extrativista Marinha do Corumbau, BA

• Autor(a) principal: Guimarães, Fernanda Jordão
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/tede/4100
• topic: Xiphopenaeus kroyer; Pesca de arrasto; Fauna acompanhante; Xiphopenaeus kroyer; Trawl fishery; Bycatch; CIENCIAS BIOLOGICAS::ZOOLOGIA

The Corumbau marine extractive reserve (MER) was the first MER specifically designed to protect coral reefs. Fishers and their families were directly dependent on extractive activities in the area. The objective of this research, was to study the biology of the sea bob shrimp Xiphopenaeus kroyeri (Heller, 1862), its fisheries aspects and evaluate the effectiveness of a bycatch reduce devices (BRD). Fish landings were daily monitored between Aug/04 and Dec/06. Shrimp samples landed (Jul/04 to Jan/07) were weekly analyzed. Monitored fisheries, in the ten main fishing grounds around the region (Jan/07 to Jan/09), were seasonally carried out. The BRD was tested (Feb/06 and Aug/06) in an experimental net, with a conded composed of a standard net (30mm mesh) and a squaremesh (50mm) front top panel (50x50cm) and compared with a net control. A total of 55.409 individuals were sampled. The CL50 found was 12.55 mm. Females reach larger sizes (CL = 38.59 mm), a higher longevity (tmax = 26 months) and had lower growth rate (kmonth = 0.17) than males (CL = 32.35 mm; tmax = 16 months and kmonth = 0.28). The sex ratio did not differ between females and males, suggesting that trawl fisheries in Corumbau MER act mainly in growth and mating areas, not in spawning locations. There was a higher female frequency in reproductive activity in the first semester, mainly related to a higher transparency, salinity and water temperature. Rare events of Tropical Water mass probably led to favorable spawning conditions, even in places near to the coast. Recruitment period was continuous with the main peak occurring in July/August. The highest juvenile abundance was associated with higher water turbidity and pH values. Trawl fishery in Corumbau MER is handmade, not going over an isobaths average of 15m. The departures are daily held, mainly focused in the morning, minimizing the need for fish cooling and reducing the operations cost. Fishing effort varied among the communities, being greatest in Corumbau, followed by Cumuruxatiba and then Caraíva. The fishing grounds use varied seasonally, often related to climatic conditions and water visibility. X. kroyeri was the most abundant penaeid (96.4%) in all communities landings, with high fishing performance in Corumbau. The higest X. kroyeri CPUEs occurred during the autumn and winter, showing a negative correlation with water visibility and temperatures, coinciding with species recruitment. Around 50% of the fisheries act on less than 15mm CL individuals size. Thus, fishing in that region, may be running in an inappropriate way to sustainable resource management. The white shrimp (L. schmitti) production was very low compared to other species, although it was present all year round, in the three communities. The pink shrimp (F. brasiliensis and F. paulensis) production was higher in Cumuruxatiba, where a clear seasonal pattern is observed. A low CPUE was registered during winter and gradually increasing over the years, with harvest peak occurring in fall. Shrimp captures were probably limited to species recruitment period. During the experiment for bycatch reduce us identified 93 fish taxa, 89 belonging to Actinopterygii Class and 3 to Chondrichthyes Class. The square mesh nets are effective in excluding bycatch without affecting the catch of sea bob shrimp. The behavior, body shape and swimming ability were crucial for fish escape success from the panel, favoring especially the larger ones. A difference in fish assemblage could be established between sampling periods, not changing the device efficiency. Besides, depth regardless, a positive effect of square mesh panel was observed. Thus, this device use is very promising tool due to its structural features, as well as having low cost, been easy to purchase and to install.