The influence of climatic factors on decomposition and disappearance of pellet-groups: case study of Persian fallow deer in Dasht-e-Naz Wildlife Refuge

Document Type : Research Paper


Faculty Member (Lecturer), Ph.D. Environmental Science Department Faculty of Natural Resources & Marine Sciences Tarbiat Modares University (TMU)


Faecal standing crop pellet group counts have been widely used in forested habitats to estimate deer population size. To convert pellet group density to deer density, Knowledge of disappearance rate of pellet groups is necessary. The disappearance rate of pellet groups may be different in different environments and can affect the accuracy of abundance estimation. We estimated decomposition and disappearance rate of Persian fallow deer (Dama mesopotamica) pellet groups in Dasht-e-Naz wildlife refuge, northern Iran, over a 12-month period. Labeling and monitoring pellet groups for decay was conducted at strip transects. Mean time ± SD to pellet group decomposition and pellet group disappearance were 94.84 ± 5.59 SE and 45.79 ± 2.71 days, respectively. Pellet groups persisted longest in summer and shortest in spring. The time to pellet group decomposition was significantly correlated with daily evaporation, mean daily air temperature and mean wind speed. The deposition of pellet groups became equal to their decay from 70-140th days and from 270-310th days since the start of the experiment suggesting a steady state system of the dung on the ground.


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