Some Perspectives on the Risks and Benefits of Biological Control of Invasive Alien Plants in the Management of Natural Ecosystems

• Published in: Environmental management (New York) 2013-09, Vol.52 (3), p.531-540
• Main Authors: van Wilgen, B. W., Moran, V. C., Hoffmann, J. H.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Applied ecology; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biological and medical sciences; Biological control; Biopesticides; Conservation biology; Conservation, protection and management of environment and wildlife; Earth and Environmental Science; Ecology; Ecosystem degradation; Ecosystems; Environment; Environmental Management; Forestry Management; Fundamental and applied biological sciences. Psychology; General aspects; Insects; Introduced Species; Invasive plants; Nature Conservation; Nonnative species; Parks, reserves, wildlife conservation. Endangered species: population survey and restocking; Pest Control, Biological; Plant populations; Plant Weeds; Quarantine; Risk Assessment; Risk aversion; Synecology; Waste Water Technology; Water Management; Water Pollution Control; Weeds
• ISSN: 0364-152X; 1432-1009
• DOI: 10.1007/s00267-013-0099-4

Globally, invasions by alien plants are rapidly increasing in extent and severity, leading to large-scale ecosystem degradation. Weed biological control offers opportunities to arrest or even reverse these trends and, although it is not always effective or appropriate as a management strategy, this practice has an excellent record of safety and many notable successes over two centuries. In recent years, growing concerns about the potential for unintended, non-target damage by biological control agents, and fears about other unpredictable effects on ecosystems, have created an increasingly demanding risk-averse regulatory environment. This development may be counter-productive because it tends to overemphasize potential problems and ignores or underestimates the benefits of weed biological control; it offers no viable alternatives; and it overlooks the inherent risks of a decision not to use biological control. The restoration of badly degraded ecosystems to a former pristine condition is not a realistic objective, but the protection of un-invaded or partial restoration of invaded ecosystems can be achieved safely, at low cost and sustainably through the informed and responsible application of biological control. This practice should therefore be given due consideration when management of invasive alien plants is being planned. This discussion paper provides a perspective on the risks and benefits of classical weed biological control, and it is aimed at assisting environmental managers in their deliberations on whether or not to use this strategy in preference, or as a supplement to other alien invasive plant control practices.