Describe how invasive non-native insects are and how the affect agricultural ecosystems and “wild” ecosystems in areas outside their native range
When an insect is dispersed outside of its native range, then the species is known as being non-native within the new ecosystem. When non-native species cause harm to an ecosystem, they are known as being invasive. Distributions going outside of the native range has been happening for over the last 300 years, where there are approximately 6,000 known established invasive insect species worldwide. Though many non-native insects can be introduced into new agricultural and wild ecosystems, not all of them are invasive. Many non-native insects can provide food and ecosystem services to new ecosystems, however most research has focussed on invasive species, and the negative aspects that they cause. Invasive species can outcompete native species for resources, as well as being a pest to agricultural crops, which often reduces yield. This has adverse effects on the economy, especially in developing countries, where they rely heavily on the income from agricultural trade. Governments have spent billions of pounds trying to eradicate and control invasive species. Though, research has found that early detection and prevention, before a species establishes itself, is the most cost effective, rather than eradication. The use of models to predict dispersal range, tighter control restrictions on borders, and the use of well-researched biological controls, can all be used to prevent unpredicted loss to the economy and to biodiversity.