Ecologia e conservação de Podocnemis expansa (Testudines, Podocnemididae) no Médio Tapajós
Visualizar/ Abrir
Data
2022Autor
http://lattes.cnpq.br/7478802635856214
FONSECA, Raphael Alves
Metadata
Mostrar registro completoResumo
P. expansa is the largest neotropical freshwater chelonian species and largest geographical
distribution, categorized as low-endangered and conservation-dependent species on the IUCN
list. In this Thesis, we start a discussion about the relationship between traditional people and
the wildlife management in Brazil, how the legal frameworks that conduct the topic are
underused and what are the prospects for the future of the management and conservation of this
specie. We investigated the P. expansa population in the Middle Tapajós region between 2013
and 2019, addressing its reproductive ecology, population structure, capture, consumption and
trade. We collected biometric data from 144 females and their eggs and nests. We found a
significant positive correlation between female and eggs amount and size, but not with nest
measurements. Female size showed a significantly positive correlation with hatching rate, as
well as nest initial height, nest height in relation to river level and substrate with predominance
of coarse sand. The Tapajós River level and substrate with predominance of fine sand showed
a significant negative correlation with the hatching rate. Through experimental captures we
captured 969 individuals, with a male-biased sex ratio was 5.83:1 . The total biomass obtained
in these captures was 4.850,8 kg. The estimated size of the population of P. expansa varied
between 296.679 and 319.084 individuals, and estimated biomass was between 1 .492,1 and
1 .604,8 tons. We applied 4.404 interviews, in which we recorded 193 captures, with 658
chelonians captured, corresponding to 3 .417 kg. The average capture frequency was 6,42 in the
dry season and 2,48 in the high season. Long-hook and “camurim” were the most used
techniques, with most captures for consumption. We found a high correlation between capture
and distance traveled to capture, distance to the Monte Cristo “Tabuleiro” and the monthly
quota of the Tapajós River. At the same time, we investigated P. expansa and P. unifilis
consumption, that differed between urban and rural areas. The P. expansa and P. unifilis
commercialized values and their eggs were higher in urban areas than in rural areas. We
conclude that it is necessary to continuous monitoring of P. expansa reproduction and
population dynamics, and that sustainable community management can be a viable alternative
for conservation, food security and income generation.