Padrão de atividade e fatores que afetam a amostragem de mamíferos de médio e grande porte na Amazônia Central
Surveying and monitoring of elusive animals with naturally low densities and large home ranges, such as many medium- and large-sized mammals, is challenging. The distribution and ecology of many species of medium- and largesized Amazonian mammals remain poorly understood. Scarcity of reliable dat...
| Autor principal: | Rocha, Daniel Gomes da |
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| Grau: | Dissertação |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Assuntos: | |
| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/11939 http://lattes.cnpq.br/5804959680157104 |
| Resumo: |
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Surveying and monitoring of elusive animals with naturally low densities and
large home ranges, such as many medium- and large-sized mammals, is
challenging. The distribution and ecology of many species of medium- and largesized
Amazonian mammals remain poorly understood. Scarcity of reliable data on
species’ occurrence and ecology can lead to weak and inappropriate conservation
actions. Additionally, low capture rates can preclude detailed analyses. We carried
out two camera-trap surveys in the dry season of two consecutive years with an
overall sampling effort of 4894 camera trap*days in Amanã Sustainable Development
Reserve, Central Amazonia. The sampling grid consisted of up to 64 baited or
unbaited camera trap stations. During the study, we recorded 22 species of mediumand
large-sized terrestrial mammals, of which 11 are categorized as threatened or
data deficient, either globally or in Brazil. The activity patters of most of the 15
medium- and large-sized terrestrial mammals species analyzed are largely
concordant with existing natural history accounts. We found weak relationships
among daily activity patterns of predators and their potential prey, and there was no
evidence of temporal segregation among large carnivores. One of the recorded
species was the bush dog (Speothos venaticus). Although its distribution covers the
entire Amazon basin, the presence of S. venaticus remains hypothetical over vast
areas of the Amazon. The records of bush dog presented in this study reduces a
large gap in the known distribution of the species in Central Amazonia, and include
the first documentation of the species from forest seasonally flooded by black water
(Igapó). We tested the efficiency of the use of trails and bait in improving capture
rates of medium- and large-sized terrestrial mammals in camera-trap surveys in the
Amazon. We also tested if the quality of photographic records of naturally marked
felids is enhanced by the use of bait. Contrary to reports in the literature, we found
that neither bait nor trails increased the number of photographic records of
carnivores, and that they reduced the number of records of non-carnivore species.
However, the quality of photographs for individual identification of naturally marked
felids was greater at baited camera-trap sites. We conclude that the use of bait and
trails should be carefully considered at the planning stage of any camera-trap studies
as they may influence detection rates of species of interest. |