Nigeria, with more than 250 ethnic groups and a current population of about 170 million inhabitants is the most populous African country. With a crude oil production of 2.5 million barrels per day, Nigeria also ranks as the largest producer of crude oil in Africa and the sixth largest producer in the world. The fisheries sector, which is also important, has grown considerably since the country gained independence from the United Kingdom in 1960. However, government fisheries departments lack officers responsible for field data collection; consequently, catch data are often exaggerated or un-reported. Using standard procedures, we re-estimated (i.e., reconstructed) the Nigerian marine fisheries catches from 1950 to 2010 to account for likely under-reporting and non-reporting of the catch of fish and shrimps trawlers, artisanal and subsistence fishers, foreign legal and illegal fleets and discards. This led to catches of about 34,000 t in 1950, 540,000 t in 2005 and 490,000 t in 2010. Reconstructed domestic catches were about twice the data supplied to the FAO. Taxonomically, sardinellas (Sardinella spp.) represented the largest contribution to domestic catches, followed by bonga shad (Ethmalosa fimbriata) and croakers (Pseudotolithus spp.). Under-reporting is becoming more pronounced over time, thus debunking the myth of massive over-reporting by Nigeria. Increasing illegal and unreported catches by foreign vessels constitute a growing threat to the sustainability of the stocks. In all, while catches are under-reported, the marine fisheries of Nigeria are overexploited.