Integrated Pest Management Program
National parks are special places which have been set aside to protect and preserve the natural and cultural resources of our nation. Life sustaining ecosystems, treasured cultural landscapes, and unique artifacts are ecologically and historically important. Managing these park resources involves the daily challenge of careful pest detection and prevention. Pests are continually present; forest pests such as gypsy moth and mountain pine beetle devastate critical ecosystems which support countless other organisms. The museum beetle, no bigger than a letter in this sentence, could quietly consume Abe Lincoln’s woolen coat or feathers from a Native American head dress for the protein meal they provide. Diligent pest detection and management is critical in protecting our national treasures and human health from pests and their damage.
How do we address pests in our national parks? Since 1980, we've used an approach called Integrated Pest Management or IPM.
What is IPM and why do we use it?
IPM is a science-based decision-making process that guides park managers when investigating a pest situation. The IPM approach determines the most appropriate and cost effective management solution for the specific pest situation. IPM includes identification of the pest, understanding the use and significance of a site or the importance of protecting a historic item, and education of the people involved. IPM also establishes pest tolerance levels and monitoring protocols. Then, with the help of technical experts and on a case–by-case basis, we develop an effective, site specific and low risk strategy to manage the pest. This includes altering conditions which attracted pests to the site in the first place. IPM often involves changing human behavior as well.
We use IPM because it works! IPM reduces risks to people, park resources, and the environment from pests and from the strategies used to manage them. We also use the IPM approach because we are directed to do so by the Federal Insecticide Fungicide and Rodenticide Act and NPS policy. We focus on finding solutions to pest problems and determine why the pest is there in the first place, rather than simply treating the damage and symptoms caused by the pest.
What would we consider a pest in a national park?
A 'pest', as defined by NPS policy, is any organism that interferes with the purpose of a park or that threatens human health or safety. A pest can be a native or nonnative organism; it can be a weed, an insect, a fungus, a disease, a fish, a bird, or a mammal; to reach "pest status” depends on the situation. An individual mouse, such as the native deer mouse for example, is a pest when inside the Yosemite Museum. Mice may damage museum items by gnawing on them or using them for nesting material. But outside the museum the same individual deer mouse is part of the natural ecosystem and is not considered a pest.
What are examples of integrated pest management tools? An example of a mechanical tool is the use of snap traps for indoor mice problems in conjunction with regular structural inspections to determine how mice are entering the structure. Then we exclude the rodents by permanently closing points of entry (for more information on rodent exclusion see “Resources” box on this page or visit: www.nps.gov/public_health/info/eh/vector/NPS_RP_Manual_v2.pdf ). Cultural IPM tools include planting disease resistant wheat to avoid the need for regular pesticide application. We use biological tools, such as Gypchek – a virus specific for gypsy moth – to manage this forest pest without affecting other non-target species, butterflies, and moths. Rather than repeatedly hand pulling deep-rooted perennial weeds and their resprouts, we may use chemical tools such as systemic herbicides that kill the entire plant, even the roots. Whereas, hand pulling annual weeds before they go to seed is an equally effective physical tool.
A great example of IPM is the well-established strategy for controlling purple loosestrife. This nonnative invasive, wetland weed destroys wildlife habitat by taking over all available growing space. Through early detection and rapid response efforts, we manage this pest with our park neighbors and others who share the waterways. Depending on the site and location, we can use herbicides to eliminate outlying patches of purple loosestrife. For dense stands of this weed, we may release a tiny biological control agent, a beetle, who eats and eventually destroys the plants. Removing purple loosestrife from wetlands allows native plants and critical wildlife habitat to return. For more information on purple loosestrife visit: http://www.nps.gov/plants/alien/fact/lysa1.htm.