Caracterização de igapós de águas claras e pretas e suas disponibilidades alimentares para o peixe-boi-da- Amazônia(Trichechus inunguis)
The Amazonian manatee (Trichechus inunguis) is a herbivore, endemic to the Amazon basin, and its distribution is related to the flood pulse and the availability of aquatic plants. It is known that it inhabits well differentiated environments, such as igapós of clear and blackwaters. It is currently...
| Autor principal: | Crema, Luciana Carvalho |
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| Grau: | Tese |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/11482 http://lattes.cnpq.br/9638668780868298 |
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The Amazonian manatee (Trichechus inunguis) is a herbivore, endemic to the Amazon basin, and its distribution is related to the flood pulse and the availability of aquatic plants. It is known that it inhabits well differentiated environments, such as igapós of clear and blackwaters. It is currently in the threat category "vulnerable" due to hunting events (historical and current), its low reproductive rate and the destruction of its habitats. Although they are extremely important, most of the studies on the Amazonian manatee's feeding were developed using stomach contents or field observations, which provide information on short-term. Through field surveys in lakes of igapós of black (Negro River) and clearwaters (Tapajós River), interviews with traditional communities in Federal Protected Areas (PAs) and analyses of stable isotopes of C and N in teeth and bones of the Amazonian manatee, I obtained information on the dynamics of food availability, biology and diet in different ontogenetic classes. Physical and chemical parameters of the water of the studied lakes varied greatly during different phases of the flood pulse. Of all the 57 species of plants registered, only 13 occurred in the two ecosystems. In the Negro River, availability of herbaceous plants is scarce and limited to vines during the period of high waters, when they had the great cognitive salience in manatees’ diet, according to interviewees. In Tapajós River there is a great richness of herbaceous plants throughout the flood pulse. The plants with highest cognitive salience were submerged with floating leaves and rooted submerged. Although there is no variation in the δ 13 C and δ 15 N signs between teeth, the differences among individuals indicate that the Amazonian manatee diet is related to the availability of resources, and their food preferences or nutritional needs. In addition, the species feeds on a variety of plants and algae, whose proportions vary according to the ontogenetic class and ecosystem. Food availability may be a determining factor in the trophic migration of the Amazonian manatee between igapós and várzeas, especially in the case of the lactating females of the lower Negro River. For this reason, the establishment of interinstitutional initiatives to guarantee the regional protection of the species, considering the possibility of movement between habitats, requires special attention. In order to reduce species threats and increase the effectiveness of Pas, greater involvement of local people and adjacent areas is needed in activities that increase their awareness of the conservation relevance of natural environments and endangered species like the Amazonia manatee. |