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Enhancing the Effectiveness of Biological Control Programs of Invasive Species by Utilizing an Integrated Pest Management Approa

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Enhancing the Effectiveness of Biological Control Programs of Invasive Species by Utilizing an Integrated Pest Management Approa U.S. Department of the Interior Oce of the Secretary C Street Washington, DC Enhancing the Effectiveness of Biological Control Programs of Invasive Species by Utilizing an Integrated Pest Management Approach Approved by isac on October 30, 2015 • the economic costs and benefits of anipm approach. Imple- PREFACE menting such efforts may increase the success of biological control efforts and the confidence of private and public land Invasive species threaten agriculture and natural ecosys- managers when making decisions about integrated invasive tems. Methods for control and management have evolved species management programs. over time, and often rely on combinations of techniques and This white paper will discuss: long-term planning. This white paper discusses the benefits and increased potential for long-term success of invasive spe- • benefits for biological control efforts through inclusion cies biological control programs when utilizing an Integrated in an ipm approach; Pest Management (ipm) approach. • partnership programs to facilitate the incorporation of Integrated control was first defined by Stern et al. (1959) as biological control in ipm programs of invasive species; applied insect pest control, which combines and integrates • incorporation of long-term stewardship in biological biological control and chemical control to maintain a pest control programs; population below an economic injury level. Integrated control • model program for integrated biological control of an has evolved over time to include all taxa, as well as prevention, invasive species; other control, and ecological, health, and economic aspects. • ecological approaches to maximize success of biological ipm emphasizes long-term prevention of damage through the control; utilization of various techniques such as chemical control, • genetic advances in biological control. biological control, physical control, habitat manipulation, modification of cultural practices, and resistant varieties • using combinations that are compatible and produce the BENEFITS OF BIOLOGICAL CONTROL desired outcome. An ipm approach can be implemented in EFFORTS THROUGH INCLUSION agricultural, residential, and natural areas.1 IN AN IPM APPROACH Biological control is an integral component of ipm pro- grams and has far greater potential for success when used in Biological control agents are intended to reduce an inva- an ipm system. Land managers rely on information provided sive species population through a typical predator-prey or by researchers during the time period leading up to the re- pathogen-host response. The incorporation of other control lease of the biological control agent (generally an insect or methods, such as chemical, mechanical, and cultural, may pathogen), to help guide them on the best procedures, ap- also help to maintain a balanced population of both predator proaches and use of the agent. As the number of biological and prey or pathogen and host. This balance minimizes the control programs increase, information from successful and chance of dramatic swings in invasive species populations, unsuccessful programs can be used to increase the chances and therefore, failure of the program. At the beginning of a for the successful establishment of biological control agents in biological control program, when an invasive species popu- the future. Post-release monitoring can inform land managers lation is large, the number of agents that can be released to on how to achieve their management goals by guiding them in achieve a noticeable population decline may not be possible. the most effective use of adaptive Best Management Practices In such cases, the use of other control methods may reduce (bmp). Post-release information is also critical for assessing the invasive species population to a level that is more respon- sive to the success of the biological control agent. An example 1 University of California Statewide ipm Program, http:// is the use of chemical and biological control on diffuse knap- www2.ipm.ucanr.edu/WhatIsIPM weed, Centaurea diffusa. Wilson et al. (2004) showed that a low 1 rate of the herbicide picloram or clopyralid applied to diffuse As an example of the increased effectiveness of biological knapweed in early summer increased the percentage of plants control through collaboration, the success of tropical soda infested by the root-boring beetle, Sphenoptera jugoslavica, apple, Solanum viarum, control with the beetle, Gratiana bo- and improved diffuse knapweed control compared with using liviana, in Florida (Diaz et al. 2012) was the direct result of the the weevil alone. cooperative effort of many individuals and organizations in- In addition to combining multiple control methods, ipm cluding U. S. Department of Agriculture-Agriculture Research approaches require a thorough understanding of the inter- Service (usda-ars), Animal and Plant Health Inspection Ser- actions between invasive species and beneficial species, as vice (aphis) and Natural Resources Conservation Service well as the dynamics of these organisms under varying en- (formerly U. S. Soil Conservation Service), University of Florida vironmental conditions and factors, all within an economic Cooperative Extension, Florida Department of Agriculture framework for assessment of costs and benefits. For exam- and Consumer Service, South and Southwest Florida Water ple, Pacific Northwestern orchard systems have several key Management Districts, and the St. Johns River Water Man- diseases and arthropod pests that detrimentally affect their agement District. aphis supported the rearing, distribution production (Jones et al. 2009). Control of these pest species and release of the biological control agents, followed by the involves the integration of selective pesticides and numerous involvement of many other agencies in the monitoring, im- species of key natural enemies. In such complex systems, plementation, and adaptive management efforts. In addition, frequent monitoring is needed to assess the population levels private landowners, primarily ranchers, also greatly assisted and seasonal phenology of target pests and natural enemy with the program by allowing access to their property for the species and to identify periods of high vulnerability to disrup- collection and redistribution of beetles. The success of these tion of natural enemies in orchards. This information is used partnerships led to the biological control program receiving to better understand the relative ecological benefits of dif- the Florida Entomological Society’s Achievement Award for ferent ipm programs. A web-based decision aid system (das) Research Teams in 2010. in Washington State was developed for pest management of Another example of a successful partnership is the rearing, apple, cherry, pear, peach and nectarine orchards (Jones et release and establishment of the parasitoids of the emerald al. 2009). The website has ten insect models and three disease ash borer, Agrilus planipennis. In this case, a Michigan lab models and integrates weather data, model predictions, and developed the production technique that provided natural pesticide recommendations (including known natural enemy in-field emergence of adult parasitoids, particularly the larval and non-target pest effects) to provide management recom- parasitoid, Tetrastichus planipennisi, and the egg parasitoid, mendations. This ipm system has been widely adopted by Oobius agrili. The lab produced over 500,000 parasites that growers and pest control advisors in many orchards in the were distributed in 17 states. usda aphis and ars, working Pacific Northwest. together, developed life table analyses for evaluation of the im- pact of the biocontrol agents, including establishment rates, • spread and parasitism levels. Adults were released into each PARTNERSHIP PROGRAMS TO FACILITATE of six forest sites where their population numbers increased THE INCORPORATION OF rapidly. Recent information indicates that 21.2% of emerald BIOLOGICAL CONTROL IN IPM ash borers were parasitized by the fall of 2015. In addition, aphis, again partnering with ars, provided data and sub- To further enhance the potential effectiveness of biological mitted a petition for release of another parasitoid species. control programs, federal land management agencies that oversee and conduct control operations utilizing biological • control agents would greatly benefit by partnering with fed- INCORPORATION OF LONG-TERM STEWARDSHIP eral, state, and local scientists and agencies. These should IN BIOLOGICAL CONTROL PROGRAMS include partnerships and collaborations from a variety of relevant pest management disciplines (Carruthers 2011). Such Federal agencies should include long-term stewardship and partnerships should develop strategies to monitor, evalu- the sustainability of desired ecosystem functions as the ul- ate/measure and communicate meaningful project results. timate goal of any biological control program. To this end, This would facilitate more effective ipm and adaptive man- part of a successful integrated pest management program agement approaches. In particular, increased emphasis on may include rehabilitation of the ecosystem to a healthier post-release monitoring data could be instrumental in the condition. Such a functional state may not be possible with decision-making process to enhance the success and eco- biological control alone. Rehabilitation practices should be nomic performance of biological control programs. To ac- developed to facilitate resilience to the ecosystem
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