Pacu fish (Cuvier, 1818) (Characiformes: Characidae) landed in Porto Velho (Rondônia) fish market from 1985 to 2004

This study evaluated various aspects of the profile of pacu (Mylossoma spp., Myleus spp., Metynnis spp.) fish marketed on the Cai N’água floating platform of Porto Velho (RO) from 1985 to 2004. Inter- and intra-annual variations in yield, variation in fish length and general characteristics of the fishing are reported. The annual pacu yield ranged from 33,000kg to 146,000kg (average = 86,585kg), representing from 6.6% to 20.45% of the total landings in the studied period. These variations followed the hydrologic cycle, and the greatest yields were recorded in the years following the highest water levels. The monthly production ranged from 0 to 42,366kg (average = 5,772kg) and it was related to reproductive migration. The pacu presented variations in standard length from 14 to 20cm (18.72cm ± 3.69, mean ± sd). The fishing was based on the use of seines and gill nets and the main environments of capture were tributaries of the low Madeira River (Jamari, Oropiara, Machado and Novo Aripuanã). The CPUE calculated for 2003 to 2005 was 15kg*fisherman 1day-1 (sd = ±21). The results show that the category constituted during this period an important resource for local commercial exploitations, as verified in other regions of the Amazon.