บทคัดย่อ :
The diversity of anurans found along a road passing through four types of habitats-dry dipterocarpous forest, dry evergreen forest, residential area and water reservior-at Sakaerat Environmental Research Station, Nakhon Ratchasima Province and their diets were studied. The anuran collection was conducted during September 2000. The purposes of this study are to determine the diet composition of each species of anurans by examining their stomach content and to compare the diet of different species of anurans in different habitat types. Four species of anurans from 185 captured individuals were identified. They are Bufo melanostictus, Limnonectes limnocharis, Kaloula pulchra and Polypedates leucomystax. The number of L. limnocharis (3) and K. pulchra (2) individuals was too low for statistical analysis, so the study was concentrated on B. melanostictus and P. leucomystax. From the stomach analysis, 5670 prey items belonging to 7 classes out of four phyla-Clitellata, Arachnida, Chilopoda, Diplopoda, Insecta, Gastropoda and Reptilia, were identified. Insects constituted the largest proportion in number and volume in B. melanostictus (94.64% and 49.09%, respectively) and P. leucomystax (82.02% and 60.67%, respectively). The diversity index of prey at family level was high in residential area (H 3.36, Hathoptera 2.56, H0.87 and Honeste 3.50). This is probably due to the large body size of toads found in this area and it is possible that insect prey was more available because they were attracted to electric lights. In case of P. leucomystax, they consumed a small amount number of prey and 55.88% of those captured had no prey in their stomach. The diets of anurans varied between B. melanostictus and P. leucomystax as well as among different habitats when the taxonomic group, trophic niche and movement behavior of prey were considered. In addition, B. melanostictus of different sexes and developmental stages (juvenile and adult) consumed different diets and males consumed a higher diversity of prey (H=2.37) than females (H=1.68) and juveniles (H=1.72). In term of niche overlap, there was low diet similarity between B. melanostictus and P. leucomystax but high within B melanostictus that appeared in different habitats.
เอกสารอ้างอิง :
Promchua, M. (2002). Dietary Composition of Bufo Melanostictus Schneider, 1799 and Polypedates Leucomystax (gravenhorst, 1829) at Sakaerat Environmental Research Station, Nakhon Ratchasima Province. Mahidol University.
