Atlas of Fish of Tapajós and Negro Rivers II: Gymnotiformes and Siluriformes

Abstract

This chapter brings photographs and detailed information on 2 orders, 9 families and 65 species of the eel like freshwater electric fishes (Gymnotiformes) and the highly diverse group of Neotropical catfishes (Siluriformes), which include many species showing a vast array of ecological characteristics, from large migratory catfishes that may be top predators, to small armored catfish that feed on algae and detritus at the bottom of rivers and lakes. These fish were sampled through standard 24 hour experimental fishing with gillnets, in lake and river sites (two sites per community) in 16 fishing communities in the Negro and Tapajós rivers (eight communities in each river), including communities located inside and outside protected areas (Extractive Reserves), as illustrated by the maps showing the distribution of fish sampled and fish catches by fishers along the two studied rivers. We also show data from fish landings in all these 16 communities, which were voluntarily recorded by fishers themselves during a participatory monitoring program. The methods used are explained in ► Chap. 2, while ► Chap. 3 brings general results of the fisheries monitoring. We show data on distribution, abundance, fish sizes, length-weight relationship plus data on fisheries, including fish biomass caught among studied fishing communities, fishing gear use, seasonality and sizes of fish caught for those groups of species that are exploited for commerce or food purposes. We grouped data for some fish species, which were more difficult to distinguish during sampling, as some species from the families Auchenipteridae and Doradidae may be particularly difficult to differentiate.