Comparações entre taxas de encontro de mamíferos de médio e grande porte em focagens noturnas, em dois períodos sazonais, na Fazenda San Francisco (Pantanal, Miranda Mato Grosso do Sul)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

Spotlighting is used to actively search for animals with research or tourism purposes. In Fazenda San Fancisco, located in the Pantanal of Miranda in the State of Mato Grosso do Sul Brazil, spotlighting is performed five to six times a week for tourism purposes. The objective of this study was to attend the tourism spotlighting activity in order to obtain an inventory of mammals of middle and large size that occur in the area. Three areas of the ranch were defined depending on the land use given: a) rice plantation area, b) cattle ranching area and c) forest reserve. Location of species were geo-referenced and plotted on a Satellite image CBERS 2 (CCD). With the data we established the encountered rate for each species observed during the wet and the dry season and the Shannon-Winner indices for three different areas. We collected data during 21 events, 11 of them happened in the dry season and 10 happened in the wet season. The total distance traveled in the farm was of 540 km, 270 km for each season, 280 km in the rice plantation area, 185 km in the forest reserve and 75 km in the cattle ranching area. A total of 15 species were observed, 5 of them only in the dry season. Twelve species were observed in the forest reserve, nine in the rice plantation area, and nine in the cattle ranching area. The highest diversity was observed in the forest reserve (1,670), followed by the cattle ranching area (1,493), followed by the rice plantation area (0.545). The majority of the observations made in the rice plantation area happened very close to the forest (less than 360 mt.) with the exception of Hydrochoerus hydrochaeris, this shows the importance of the forest edge effect. Density during wet and dry season respectively for the different species are as follows: Marsh deer (Blastocerus dichotomus) 0,273 0,080 indiv./km2; 0,301 0,088 indiv./km2; Capybara (H. hydrochaeris) 12,965 2,081 indiv./km2; 28,959 5,449 indiv./km2; Crab-eating fox (Cerdocyon thous) 0,919 0,306 indiv./km2; 2,034 0,621 indiv./km2; Ocelot (Leopardus pardalis) 0,428 0,052 indiv./km2; 0,516 0,149 indiv./km2. The encounter rate for the giant ant-eater (Myrmecophaga tridactyla) was of 0,007 indiv./km in the wet season and 0,140 indiv./km in the dry season; we could only calculate the density of the species in the dry season which was of 1,054 indiv./km2. The group density for H. hydrochaeris was also higher in the dry season 4,295 0,514 groups/km2; than in the wet season 6,072 0,819 groups/km2. For all species with exception of the Maned Wolf (Chrysocyon brachyurus) all encounters rates were higher during the dry season than during the wet season. We conclude that in Fazenda San Francisco the best time of the year to observe the most species would be the dry season, this data could be used for the advance of the tourism activity. Diversity of mammals in is forest - dependent, we observed more species in the Forest Reserve and close to the forest edge than in other ecosystems. This information could be useful in the planning of landscape use considering the importance of forest corridors in the different activities for which Pantanal land is traditionally used.

ASSUNTO(S)

spotlight pantanal encounter rate focagem noturna ecologia aplicada pantanal taxa de encontro mamíferos mammals

ACESSO AO ARTIGO

Documentos Relacionados