Control of mammalian predators in game management and conservation.

Abstract

Wildlife management in modem environments has to contend with an inheritance of faunal and landscape changes caused by humans which affect the relationships between predatory and prey species. In both game management for harvesting, and in species preservation, this leads to difficult decisions about whether and how to manage predation.
Predator control by humans is as old as livestock husbandry. The deliberate, often organized, destruction of many mammalian predator species has been a feature of human development in Europe - and later in countries to which Europeans spread - for centuries. Destruction to the point of extinction was practised for a number of reasons (self-protection, protection of domestic stock, protection of wild game, fur, adventure, sport) which were rarely distinguished. Reduction of predator numbers specifically to allow an increased harvest of some game species was mainly a nineteenth century development, while the adoption of predator control to benefit endangered species for their own sake belongs to recent decades.
We review scientific literature relevant to predator control in game management and in conservation. Understanding of the role of predation in prey population dynamics has changed considerably during the last 20 years, and predation is now credited with a much more powerful role than in the past. Increasingly it becomes possible not merely to understand what predator control achieves, but to predict when it might be valuable in management, and what strategy will best achieve the aims.
Examples of conservation problems involving predation illustrate the complexity of decision-making in management. Because of habitat loss, habitat degradation, altered predator communities, or altered predator-prey ratios, predation losses often have increased significance in modem environments.
Novel approaches potentially offer non-lethal ways to manage mammalian predators. However, most are still in an exploratory phase and there have been no unqualified successes. The best tested approach, excluding predators from small areas by fencing, is discussed.
In Britain, predator control to benefit small game populations and allow harvesting has been practised for nearly 200 years, and has undoubtedly played a role in shaping the present-day fauna. Although earlier gamekeeping severely reduced the geographical range of several mammalian (and avian) predator species, nowadays predator control is subject to legal restrictions based on species' conservation status and humaneness. However, illegal persecution of species protected by law remains a persistent and significant conservation problem. The predator species legitimately targeted are successful, common and increasing in the modem environment, while wild populations of gamebirds and many other ground-nesting birds are declining seriously in most areas.