Litopenaeus schmitti is one of the most commercially exploited penaeids on the southeastern and southern Atlantic coast of Brazil. Information about juvenile recruitment and growth patterns of individuals is important for management programs. The present study estimated the growth parameters, longevity, and recruitment of L. schmitti in the region of Ubatuba, São Paulo State. The growth parameters of individuals were estimated by the Bertalanffy growth model, and longevity was estimated with the inverted Bertalanffy equation. The growth parameters were, for females and males respectively: CL ∞ = 53.10 mm and 43.23 mm, k = 1.82 year -1 and 2.19 years -1 , t 0 = 1.10 and 0.69. Longevity was calculated to be 2.27 years for females and 2.10 years for males. Juvenile recruitment occurred seasonally from December to April during the first year of sampling and from November to May in the second year. Although the large peak in juveniles seen in March 2007 in the estuarine regions coincided with the closed season, the reopening of the fishery in June may promote the capture of large numbers of newly grown adults who have not yet reproduced.

Xiphopenaeus kroyeri (Heller, 1862) is the third most common species caught by fi shing boats in the state of São Paulo, Brazil and production of this shrimp in the Cananéia region located on the southern coast of this state ranks second in the nation. Th e aim of this study was to investigate the temporal variation of the total biomass and size of X. kroyeri and analyze this variation against environmental factors in order to suggest some information about the best periods to fi sh this species. Samples were caught monthly from four sampling stations in Cananéia between July 2012 and June 2014 using a fi shing boat equipped with ott er-trawl nets. Temperature and salinity were monitored using a multiparameter probe, and sediment samples were also taken using a Van Veen-type gripper for particle size analysis. Th e shrimp were weighed, quantifi ed, and carapace length was measured (mm). In general, the highest total biomass values were recorded when the fi shery was closed in the southeast and south regions, and the highest catch of smaller individuals was also observed during this period. In contrast, in November 2013 the fi shing is permitt ed and high biomass composed of large individuals was observed. Th e monthly biomass showed a positive relationship with sediment texture, because this species prefers very fi ne sediments to burrow as a defense against predators. keY wordsAbundance, closed season, fi shery, Penaeidae, weight. Miazaki et al.2

The study characterized the structure of juveniles and sub-adults of Farfantepenaeus brasiliensis and F. paulensis in the Cananéia-Iguape estuarine lagoon system and its adjacent coastal area by evaluating the period of juvenile recruitment, sex ratio, growth, longevity, natural mortality, and development time until the late juvenile phase. Samples were collected from July 2012 to June 2014. Shrimps were identified by species and sex, and measured (carapace length – CL mm); 889 individuals of F. brasiliensis and 848 of F. paulensis were analysed. Females were more abundant than males for both species. The growth parameters of F. brasiliensis were: CL∞ = 45.5 mm, k = 1.8 year−1 for males and CL∞ = 55.2 mm, k = 1.6 year−1 for females; longevity of 2.52 years (males) and 2.88 years (females); and natural mortality of 1.71 (males) and 1.55 (females). For F. paulensis, the following values were observed: CL∞ = 40.7 mm, k = 2.3 year−1 for males and CL∞ = 56.5 mm, k = 1.9 year−1 for females; longevity of 2.04 years (males) and 2.37 years (females); and natural mortality of 2.39 (males) and 2.05 (females). The juvenile recruitment of both species peaked in January 2014. The development time until late juvenile phase was ~7 months (F. brasiliensis) and ~5 months (F. paulensis). Even though the highest abundance of juveniles did not occur in the closed season, fishing is forbidden in the estuarine area and the migration towards the adult population occurred close to or even during the closed season.

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