Anthropogenic Food Subsidy to a Commensal Carnivore: The Value and Supply of Human Faeces in the Diet of Free-Ranging Dogs
Open Access
- 26 April 2018
- Vol. 8 (5), 67
- https://doi.org/10.3390/ani8050067
Abstract
As the global population of free-ranging domestic dogs grows, there is increasing concern about impacts on human health and wildlife conservation. Effective management of dog populations requires reliable information on their diet, feeding behavior, and social ecology. Free-ranging dogs are reliant on humans, but anthropogenic food subsidies, particularly human faeces (i.e., coprophagy) have not previously been fully quantified. In this study we assess the contributions of different food types to the diet, and their influences on the social behaviour of free-ranging dogs in communal lands of rural Zimbabwe, with a focus on coprophagy. Free-ranging dog diets, body condition, and sociology were studied amongst 72 dogs over 18 months using scat analysis and direct observations. Human faeces constituted the fourth most common item in scats (56% occurrence) and contributed 21% by mass to the observed diet. Human faeces represented a valuable resource because relative to other food items it was consistently available, and of higher nutritional value than ‘sadza’ (maize porridge, the human staple and primary human-derived food), yielding 18.7% crude protein and 18.7 KJ/kg gross energy, compared to 8.3% and 18.5 KJ/kg for sadza, respectively. Human faeces had protein and energy values equivalent to mammal remains, another important food item. Dog condition was generally good, with 64% of adult females and 74% of adult males in the highest two body condition scores (on a five point scale), suggesting a plentiful and high quality food supply. Dogs largely fed alone, perhaps as a consequence of the small, inert, and spatially dispersed items that comprise their diet, and its abundance. We discuss the relationships between sanitation, human development, the supply of human faeces, female dog fertility, and population control.This publication has 28 references indexed in Scilit:
- Dropping dead: causes and consequences of vulture population declines worldwideAnnals of the New York Academy of Sciences, 2011
- Competition between domestic dogs and Ethiopian wolf (Canis simensis) in the Bale Mountains National Park, EthiopiaAfrican Journal of Ecology, 2010
- Dietary Niche Separation between Sympatric Free-Ranging Domestic Dogs and Indian Foxes in Central India: Table 1Journal of Mammalogy, 2009
- Free-ranging domestic dogs (Canis familiaris) as predators and prey in rural Zimbabwe: threats of competition and disease to large wild carnivoresBiological Conservation, 2004
- The economic costs of wildlife predation on livestock in Gokwe communal land, ZimbabweAfrican Journal of Ecology, 2000
- Diet and Feeding Behavior of Ethiopian Wolves (Canis simensis)Journal of Mammalogy, 1995
- The diet of the spotted hyaenas Crocuta crocuta in Kruger National ParkAfrican Journal of Ecology, 1990
- Assessing the Diet of Dingoes from Feces: A Comparison of 3 MethodsThe Journal of Wildlife Management, 1989
- Certain behavioral features in the pariah dog (Canis familiaris) in West BengalApplied Animal Ethology, 1975
- A Field Technique for Assessing Physical Condition of Some UngulatesThe Journal of Wildlife Management, 1960