抄録
Results of the point-frame (PF) method and the frequency (FR) method were compared by use of 340 fecal samples of the raccoon dog (Nyctereutes orocyonoides) collected in the western suburb of Tokyo, Japan. The fecal contents were categorized into 63 food categories. Proportion of each food category to the fecal composition (P%) and frequency (F%) were determined. Twelve food categories whose P% were >2% were selected as "important food categories". Their annual F% ranged from 5.9% (potato) to 64.8% (monocot leaves). The high F% and great P% type included monocot leaves and insects. The high F% and small P% type included forb leaves and browse leaves which are frequently available but not preferably utilized by the raccoon dog. The low F% and great P% type included mushroom and gingko nut. These foods are seasonal and preferably utilized by the raccoon dog. Other 6 categories had low F% and small P%. The PF method is advantageous in that it is precise, time-saving, and provides FR as well. Synthetic use of both F% and P% by the PF method is recommended, because the combination of P% and F% provides the ecological significance of the characters of foods and F% evaluation without P% or based on a small sample size is imprecise or less informative.
