As custodians of a large proportion of land surface, farmers have an important role to play in biodiversity conservation efforts. Biodiversity can directly benefit farming enterprises by providing shelter for stock, timber, environments where natural enemies of pest species can hide and other resources. With respect to pests’ natural enemies (parasitoids and predators), the increased biodiversity is of value to growers, as it has potential economic benefits – contributing to increased pest control and reducing the necessary input of chemicals.

Promoting biodiversity on farmland in an effort to enhance natural enemy contribution to pest control can benefit all parts of biodiversity, including birds and mammals that feed on insects and even fish in waterways and wetlands, through reduced chemical inputs. When diversity is low, there is an increased cost of controlling pests both in economic terms, based on chemicals and labour, and in environmental terms, although environmental benefits and costs are rarely computed.

Invasive species are of particular concern in Australia, which is free of several highly damaging pests and diseases. Increasing travel and recent climate change are both contributing to enhanced risk of invasion despite vigilance. Once pest species enter a country and immediate control programs around the point of entry fail, there is normally a period where pests are particularly damaging, followed by a period where local species may start to provide some control via predation, competition or herbivory, although in some situations the importation of exotic agents may be required.