Introduction

Across the world, vertebrates cause considerable annual damage to agriculture, property, human health and safety, and natural resources. Although some species of all vertebrate groups have been implicated in damage, the species most often involved in serious amounts of damage are birds and mammals. Agroecosystems have provided many new opportunities for vertebrates to exploit, resulting in their becoming serious “pests” with humans taking various steps to protect their agricultural resources. This conflict has intensified as the human population has increased, efforts to get more production out of traditional croplands have intensified, and marginal lands have been placed into crop production. Additionally, as the human population has increased, people have moved into lands occupied by wildlife, resulting in more human–wildlife encounters and conflicts.

Worldwide, the kind of damage caused by wildlife is most often related to the life history strategy of the species, although the actual species and crop involved varies greatly from region to region. In most cases, the conflict arises when wildlife are trying to acquire adequate food resources (i.e. meet nutritional needs) and forage on resources important to, and “reserved” by, humans. Examples can be identified from almost any region of the world for (1) carnivore predation on livestock, highly valued game animals, and endangered wildlife; (2) grain losses to flocking, seed-feeding avian species; (3) grassland rodents and lagomorphs consuming seeds and green foliage that would otherwise be available to livestock; (4) herding ungulates trampling and consuming crops and seedlings planted for reforestation; (5) aquaculture losses to fish-eating birds; and (6) disease transmission from wildlife to humans or their livestock (Conover, 2002; Dolbeer et al., 1994).