The ECOSAR cruises were a component of the project "Prospecting and evaluation of sardine biomass on the south-east coast by hydroacoustic methods" carried out by the Department of Oceanography of the Federal University of Rio Grande. It sampled the Southeast Continental Shelf of Brazil between Cabo Frio (22º30'S ) and Cabo de Santa Marta (28º30'S). Two ECOSAR cruises were incorporated into the database, the second (ECOSAR_2) conducted from June to July 1995, and the third (ECOSAR_3) cruise conducted from November to December 1995. The sample design resulted in 28 transects (27 in the 3rd cruise) perpendicular to the coastline carried out with the research vessel Atlantico Sul. The effort resulted in 125 oceanographic stations sampled during ECOSAR_2 and 85 stations during ECOSAR_3. Stations were spaced 20 nautical miles (~ 37 km) apart with the eastern limit on the 200 m isobath (Freitas & Muelbert, 2004).The ichthyoplankton samples were obtained through oblique trawls conducted between the surface and 5 m depth above the bottom in the shallow stations, and from 200 m depth in the deep stations. The vessel speed was kept constant at 1 m/s (approximately 2 knots). Plankton was sampled with a 0.6 m of mouth diameter Bongo net suited with a 330 µm (300 µm in the 3rd cruise) mesh and equipped with flowmeter to determine the volume of filtered water in each trawl. The samples were fixed and preserved in formaldehyde solution, buffered with sodium tetraborate, diluted in sea water with a final approximate concentration of 4%. The filtered volume was calculated and used to standardize the abundance of fish eggs and larvae per 100 m3 of filtered water. The identification of the eggs and larvae was conducted only for the ECOSAR_2 cruise (Freitas & Muelbert, 2004).