Visualizar Tese - Instituto de Biociências - Unesp

Visualizar Tese - Instituto de Biociências - Unesp Visualizar Tese - Instituto de Biociências - Unesp

20.04.2015 Views

Às minhas filhas, Camila e Carolina, os meus mais sinceros agradecimentos. Primeiro, pelas horas roubadas do convívio familiar, depois, pela abnegação, pelo incentivo, pelo carinho e pela força que tiveram na minha ausência constante...em todas as reuniões da escola que não compareci, aos anos de adolescência que eu não vi...porque estive longe ou ausente. E pela troca de idéias e sugestões, que depois de crescidas, freqüentemente trocaram comigo, no decorrer deste trabalho. Amo infinitamente vocês! Finalmente, mas não por último e obviamente, não menos importante, ao pai delas, Jiri Antonin Sazima, por infinitos motivos, mas principalmente, por fazer de mim uma mulher forte. E acima de tudo, a Deus, por ter colocado todas essas pessoas no meu caminho. ABSTRACT The artisanal fishery which uses basically gillnets is the main economic activity of traditional fishermen in the great dams in the national territory including the main axis in the Tiete River. This work aimed at studying the composition, fish making and evaluates empirically the sustentability of the fishery made by artisanal fishermen in the comprised area between Três Irmãos Dam and the Hydroelectric Power dam of Nova Avanhandava (in the lower Tiete River).

Four years of study were done and in the three first ones (1998,1999 and 2000) 30.201 samples were shown in the fish landings belonging to 71 species of fishes being these grouped into 19 families, 47 genera and four orders (Characiformes, Siluriformes, Gymnotiformes and Perciformes). Of all these species the ten found in more abundance were: The corvine (Plagioscion squamosissimus), the taguara (Schizodon nasutus), the acarajéu (Satanoperca pappaterra), the pacuprata (Metynnis mola), the piranha (Serrasalmus maculatus), the mandi (Pimelodus maculatus), the caborja (Hoplosternum littorale), the cascudo-amazonas (Pterygoplichthys anisitsi), the traíra (Hoplias malabaricus) and the cascudos claros (Hypostomus sp.1), representing 76,23% from the total samples. Still between these ten species, the exotic/introduced represented half of the most abundant ones, being P. squamosissimus, S. pappaterra, M. mola, H.littorale and P. anisitsi. In the last year of work in 2006, only 2.486 samples were shown, also including a new species that was found : the porquinho (Geophagus proximus), making it 72 species and 48 registered genera in the four years of study totalizing 32.687 shown species. Within the four years, the introduced species P. squamosissimus leaded the ranking in numbers of individual and biomass; and in this last year it was responsible alone for 47% of the fish landings. Capture data per unit of effort and the ecological attributes show a very critical and worrying situation, for it’s clearly noticed that there was a drastic decrease in the number of species, as well as in the number and in the biomass of the last collected samples in the last year of study. The most plausible hypothesis to this serious situation would be the great number of exotic/introduced species which are competing with the native ones,

Às minhas filhas, Camila e Carolina, os meus mais sinceros<br />

agra<strong>de</strong>cimentos. Primeiro, pelas horas roubadas do convívio familiar, <strong>de</strong>pois, pela<br />

abnegação, pelo incentivo, pelo carinho e pela força que tiveram na minha ausência<br />

constante...em todas as reuniões da escola que não compareci, aos anos <strong>de</strong><br />

adolescência que eu não vi...porque estive longe ou ausente. E pela troca <strong>de</strong> idéias e<br />

sugestões, que <strong>de</strong>pois <strong>de</strong> crescidas, freqüentemente trocaram comigo, no <strong>de</strong>correr<br />

<strong>de</strong>ste trabalho. Amo infinitamente vocês!<br />

Finalmente, mas não por último e obviamente, não menos importante, ao<br />

pai <strong>de</strong>las, Jiri Antonin Sazima, por infinitos motivos, mas principalmente, por fazer <strong>de</strong><br />

mim uma mulher forte.<br />

E acima <strong>de</strong> tudo, a Deus, por ter colocado todas essas pessoas no meu<br />

caminho.<br />

ABSTRACT<br />

The artisanal fishery which uses basically gillnets is the main economic<br />

activity of traditional fishermen in the great dams in the national territory including the<br />

main axis in the Tiete River.<br />

This work aimed at studying the composition, fish making and evaluates<br />

empirically the sustentability of the fishery ma<strong>de</strong> by artisanal fishermen in the comprised<br />

area between Três Irmãos Dam and the Hydroelectric Power dam of Nova Avanhandava (in<br />

the lower Tiete River).

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