Modelling carcass disposal practices: implications for the management of an ecological service provided by vultures.
Abstract
In many European countries, private companies are in charge of livestock carcass disposal. In agro-pastoral systems, however, scavengers such as vultures provide an alternative ecological service for disposing of carcasses. By combining interviews with farmers and ecological data from the Grands Causses region (southern France), we developed an agent-based model to assess the environmental and economic consequences of various farmers' carcass disposal strategies, involving private companies and/or vultures. The model includes 'offering' vulture feeding behaviour, as an ecological service, and farmer choices of carcass disposal system, representing the 'demand' for this service. This ecological service can provide benefits through reducing monetary costs and carbon emissions associated with carcass disposal, but also represent a sanitary risk if vultures fail to remove carrion efficiently. Benefits and risks strongly depend on carcass disposal techniques and the wider strategy. The most sustainable strategy to match the 'demand' and 'offer' for carcass disposal involves the adaptive use by farmers of both the ecological and the industrial services. This strategy enables the optimization of the ecological service benefits while minimizing sanitary risks by using a private company service, when carcass disposal by vultures is uncertain. Synthesis and applications. In cases where there is a mismatch between the demand and the offer, negative feedback can occur for both humans and vultures. Preserving vulture populations and enhancing benefits from the sustainable service, they provide might henceforth be explicitly accounted for in legislation and carcass management guidance, in accordance with vulture food requirements. The agent-based modelling approach described here offers a tool that can guide management strategies and policies and support coordination among stakeholders.
Key words
- animal behaviour
- animal feeding
- behaviour
- carcass disposal
- carcasses
- carrion
- companies
- conservation
- costs
- disposal
- domestic animals
- ecology
- economic impact
- farmers
- feedback
- feeding
- feeding behaviour
- interviews
- legislation
- livestock
- models
- natural enemies
- nutrient requirements
- optimization
- policy
- predators
- predatory birds
- risk assessment
- stakeholders
- synthesis
- techniques
- wastes