This paper includes an analysis of the length distribution of Sardine landed from the Lagoon of Cananéia in the south of the State of São Paulo, Brazil, in which it is shown that young Sardines appear in the catches during October, grow quickly until about January, and then more slowly until they reach the length of 14 cm in April. They then disappear from the Lagoon. A correlation is made between the landings of larger Sardine in Rio de Janeiro and the small Sardine landed in Cananéia the previous year. It is suggested that the abundance of Sardine landed in Cananéia may be used as an index of abundance in the following year at Rio de Janeiro.