[ Invasive species are very expensive to control, costing $1.4 trillion world-wide. The annual cost of impact and control are equal to 5 percent of the world economy. Invasive species reduce the yield and quality of food crops and livestock forage plants, kill trees, lower drinking water quality, reduce energy production, and decrease native biodiversity. Weedy species are expanding exponentially faster than the number of acres treated and restored every year, doubling the number of acres invaded every 8 years.
We need to take action now. Control will be even harder after oil declines, and unlikely to be at the top of the oil-rationing priority list. On the other hand, we need to be careful about how we get rid of invasive species, since some of the treatment consists of health-harming pesticides. Let’s not repeat the disaster of what happened across the South when massive amounts of toxic chemicals were used to eradicate the fire ant to no effect (see The Fire Ant Wars by Joshua Buhs).
A few of the findings from the 2014 House of Representatives session on “Invasive species management on federal lands”:
- Over 100 million acres (an area roughly the size of California) in the United States are suffering from invasive plant infestations.
- The U.S. Environmental Protection Agency estimates the U.S. spends at least $138 billion per year to fight and control invasive plant and animal species
- Some of the most damaging Invasive species include Asian Long-horned Beetle, Emerald Ash Borer, Gypsy Moth, Sudden Oak Death, Hemlock Woolly Adelgid, and Cogon grass. Municipal governments across the country are spending more than $1.7 billion each year to remove trees on city property killed by these pests.
- The maximum economic impact potential of losing 1.2 billion trees from attack by Asian long-horned beetle is $669 billion.
- Hemlock Woolly Adelgid has killed up to 90% of hemlock trees in the Appalachians from Georgia to Massachusetts. Loss of hemlock groves threatens unique ecosystems and watersheds.
- About $16–$44 million dollars of hydropower generation is lost annually due to the salt cedar invasion in the United States.
- S. agriculture loses $13 billion annually in crops from invasive insects, such as vine mealybugs
- On a scale of biodiversity destruction, the EPA reports that invasive species rank second only to urban development.
Alice Friedemann www.energyskeptic.com author of “When Trucks Stop Running: Energy and the Future of Transportation, 2015, Springer]
House 113-18. May 16, 2014. Invasive species management on federal lands. House of Representatives. 72 pages.
Rob Bishop, Utah. The proliferation of invasive species on our public lands is impacting the health, the landscape, and it is increasing the risk of wildfire, affecting wildlife habitat, impacting the viability of land for multiple use, and perhaps most troubling, it is undermining the efforts of their neighboring land owners, who, unlike the Federal Government, are often taking proactive steps to reduce the threat of invasive species on their lands. This hearing is intended to take a first look at this issue. We are going to hear from the Forest Service about their efforts to tackle the growing threats to the 193 million acres that it manages. The Department of the Interior, unfortunately, chose not to talk to us about the 400 million acres that they manage.
PAUL RIES, Associate Deputy Chief, State and Private Forestry, U.S. Forest Service, U.S. Department of Agriculture
Invasive species are among the most significant environmental and economic threats facing our Nation.
Aquatic and terrestrial invasive plants, pathogens, vertebrates, invertebrates, algae, and fungi have become established on millions of acres across North America.
These infestations are degrading watershed condition and ecosystem functionality, reducing forest and rangeland productivity, increasing the risk of wildfire and soil erosion, causing declines in recreational use and enjoyment, negatively impacting human health and safety, threatening native fish and wildlife populations and their associated habitats, causing declines in property values, and undermining the economy at all levels.
Invasive species cause billions of dollars in damage each year in the United States. Pimentel et al. (2001) estimated damage from invasive species world-wide totaled at more than $1.4 trillion per year.
Forest Service invasive species management performance is outcome driven, with a focus on treating and restoring priority areas to improve watershed condition and reduce the long-term impacts of invasive species. To achieve this, national forests and grasslands typically treat nearly 400,000 acres of priority aquatic and terrestrial invasive species infestations annually using an integrated management approach. Since 2007, more than 2 million acres of lands and waters have been restored to protect against aquatic and terrestrial invasive species across National Forest System lands and waters.
The Forest Service provides technical and financial assistance to State natural resource and agricultural agencies, tribal governments, and other Federal land management agencies to respond to and manage forest pests that threaten the Nation’s 851 million acres of rural and urban forests of all ownerships.
In FY 2012, Forest Service Research and Development delivered 169 invasive species tools including the identification of key pathways for invasion by new forest pests; methods for detecting, monitoring, and controlling the walnut twig beetle; release and recovery guidelines for biological control agents for emerald ash borer; and an assessment of the potential impacts of hemlock woolly adelgid predators.
The Forest Service International Programs also work to protect our forests from invasive species damage. For example, the program works with Chinese counterparts who have partnered with us to address one of the most destructive invasive forest pests, the emerald ash borer (EAB). The Forest Service continues to work with the USDA Agricultural Research Service (ARS) to better understand why the borer is so resilient and pervasive.
K. GEORGE BECK, Professor of Weed science, Colorado State University, Healthy Habitats Coalition
The data on this particular slide show the number of infested acres in 2009, acreage treated and restored and the increase of infested acres for six Federal agencies that have a responsibility to manage invasive species. Only 3.2% of existing infested acres were treated and restored in 2009. Weed scientists indicate that invasive weeds typically spread at a rate of 12 to 16% a year. Treating and restoring only 3.2% of infested acres annually, coupled with a 12% increase, indicates that Federal infested acres will double by 2017 and will surpass 100 million acres at that time.
Federal agencies are acquiring about 3.5 times more acres of invasive weeds annually than they are treating and restoring. This plan decidedly will never be successful and will continuously produce more and more infested acres, thus preventing realization of land management goals and objectives. Just as importantly, however, these ever-expanding acres of invasive weeds on federally managed lands will serve as a constant source of propagules to disperse to new locations.
These data show the National Invasive Species Council budget, which is assembled by asking the agencies for what they have done, and putting those figures into one of these seven budget categories. The Federal Government spent $1.563 billion in fiscal year 2009 on invasive species management, stating that $642 million was spent on control and management. HHC members have years of experience designing weed management plans, and our calculations differ substantially from the Federal data.
Agencies indicated they treated and restored 1,603,805 acres in 2009. Our calculations suggest the following when early detection/rapid response is budgeted at $1,000 per acre, restoration at $300 per acre, and controlled herbicide at $100 per acre. As you can see, our calculations indicate that far less appears to have been spent on control and management than that stated by the Federal agencies, and there remains about $305 million that cannot be readily placed into one of the next budget categories.
It appears, then, that agencies are spending more money per acre to control invasive weeds than is necessary. The Healthy Habitat Coalition recommends that Federal agencies must treat and restore at least 15% of infested acres annually to overcome this management deficit.
The data in this table show that within 10 years, 19.2 million acres would be treated and restored using this plan, which represents a 39% decrease of infested acres, as opposed to over 120% increase using their current approach over the same time period.
In addition to treating and restoring many more acres annually than Federal agencies currently do, they also must be more efficient and effective with taxpayer dollars. Many university extension professors have spent considerable effort over the past 25 years educating and training Federal personnel about invasive weeds and their management. The inadequate Federal performance in spite of this extensive educational effort by so many also suggests, then, that their efforts are likely insufficient. We, as a Nation, are digressing, rather than progressing, on invasive species management.
Invasive species is an insidious and occasionally sinister economic and environmental issue—it is not new.
The Canada thistle, for example, was first declared noxious in the United States in 1795 in Vermont. A little overgrazing by one user, in this instance, opened the door for invasion of the common area by Canada thistle, which in turn decreased everyone else’s ability to raise the sustenance needed to survive. It was the tragedy of the commons where one person’s use of the environment influenced the next person’s use and invasive species continue to plague us in this fashion to this day.
In spite almost three decades of work with the Federal Government to control and manage invasive species, little progress has been made and what progress that has occurred is grossly insufficient on a national scale. A multitude of taxa require our immediate management attention; zebra and quagga mussels, New Zealand mudsnails, Burmese pythons, feral hogs, emerald ash borers, gypsy moths, Asian carp, snakehead fish—the list of invasive species is long.
The Healthy Habitat Coalition’s collective experience, however, is with invasive weeds and we will focus on the continued growth of various weed species and the need for better control and management measures on lands and waterways throughout the country. The data in Table 1 outline the amount of infested acres, the amount of acres treated, and the increase of infested acres for the six major Federal Agencies who have jurisdiction over invasive species.
Totals from table 1: Infested acres 49,481,709, Treated & restored acres 1,603,805, Percent treated and restored 3.2%, New Acres Annually 5,769,349, Total Net Infested Acres 53,847,807 (2009), over 110 million acres infested in 2018 due to not enough treatment done per year
As with other integrated management systems for weeds, use of fire to manage invasive weeds must be integrated with other tools such as seeding to provide competition to ward off recovering weed species and allow completion of land management goals and objectives. Burning mixed brush-cheatgrass stands destroys some to many weed seeds and allows for about one season to establish desirable vegetation before cheatgrass re-establishes and dominates the site again
Establishing competitive perennial grass species may successfully keep cheatgrass from re-establishing. If, however, the system is left alone after burning, cheatgrass or medusahead will re-invade. Burning stands of yellow starthistle also will provide excellent population control if combined with herbicide treatment and seeding (DiTomaso et al. 2006b). Burning stands of perennial weeds such as Canada thistle, leafy spurge, Russian and other knapweeds, or tamarisk rarely is effective because of the plants’ capability to re-grow from its root system and dominate a site again.
These and other similar invasive weeds may recover soon enough after a prescribed burn to preclude establishment of seeded species. If fire is used to control perennial forbs or grasses, herbicides likely will have to be integrated into the management system to allow sufficient suppression of the target weed for a long enough time to give seeded species the opportunity to establish.
The decision to do nothing seems inexpensive and harmless on the surface but nothing could be farther from reality. The problem with invasive species is their populations always seem to expand and cause harm, albeit, a species can be problematic in one location or setting and not another. Most invasive species and certainly invasive weed populations develop in a sigmoid curve pattern and after a lag time following introduction, their populations increase exponentially until site saturation when their populations are limited by resource availability.
The problem is one never knows where on the curve the population at any given population lies. Even with cheatgrass, the invaded location/site might be new and at the bottom of the curve when population control is most easily obtained or it could be at beginning of the exponential phase but it is difficult at best to make such a determination. The best response is to NEVER DO NOTHING because doing nothing can be the most expensive decision one can make due to the subsequent population growth by the invasive weed and the resulting havoc it wreaks upon the native plant community and the animals it supports! Doing nothing simply yields the site to the invasive species.
The least expensive weed to control is the one that is not present—however, prevention is not free. The perception that prevention is simply steps taken to keep stuff out that currently does not exist in a particular location is accurate for certain and possibly represents the greatest cost savings to taxpayers. Cleaning equipment between uses and locations seems a logical prevention approach along with using certified weed seed-free hay, forage, mulch or gravel, and careful screening of ornamental and agricultural introductions can be of tremendous benefit in the battle against invasive species.
Prevention also means decreasing population abundance of existing weed infestations so they are not a source for new ones to develop some distance— close or far— from the infested site.
Diffuse knapweed (Centaurea diffusa) was targeted in Colorado where hand pulling twice annually was compared to mowing three times annually, to mowing twice followed by herbicide in fall, to herbicide application alone. Control of diffuse knapweed rosettes and bolted plants was best 1 year after treatments were exerted where a herbicide was used alone or in combination with mowing compared to mowing alone or hand pulling. Herbicides alone were about 1 percent of the total cost of hand pulling and the latter was completely ineffective.
Duncan and Clark (2005) cite numerous examples of the environmental and economic impacts caused by invasive weeds. Pimentel et al. (2005) calculated that invasive species impact the U.S. economy by more than $120 billion annually and $36 billion of this was caused by invasive weeds.
Some examples of plants and plant pests that move in interstate and foreign commerce that have become problems for State inspection, quarantine, agriculture, and natural resource authorities include:
- Arunda donax; common name giant reed; imported as an ornamental in many U.S. States and now being considered for biofuel production.
- Pennisetum setaceu; fountain grass; imported as an ornamental and now one of Hawaii’s most damaging invasive plant species.
- Imperata cylindrica; cogongrass; used as packing material and imported for forage and erosion control. Now an aggressive invasive species problem in the Southern and Eastern United States as far north as Michigan.
- Anoplophora glabripennis;
- Asian longhorned beetle; accidentally introduced in wood packing materials; destructive wood boring pest expanding its range in the United States.
- Agrilus planipennis; emerald ash borer; arrived accidentally in cargo from Asia; first discovered in Michigan in 2002 and since spread to 17 other States in upper Midwest and Northeast.
- Lythrum salicaria; purple loosestrife; introduced as an ornamental but now prohibited in most States. Considered by some to be the poster child for invasive species.
- Sturnus vulgaris; European starlings; introduced into New York 1890s and have since spread across continental United States and may even be helping to spread other invasive species such as Russian olive (Elaeagnus angustifolia).
A few examples of costs to States for invasive species that have arrived via interstate and foreign commerce and then become established in States are:
- Emerald ash borer in Ohio projected costs for landscape value losses, tree removal and replacement range from $1.8 to $7.6 billion (in Ohio alone).
- Data from nine U.S. cities Atlanta, GA; Baltimore, MD; Boston, MA; Chicago, IL; Jersey City, NJ; New York, NY; Oakland, CA; Philadelphia, PA; and Syracuse, NY) indicates maximum economic impact potential of losing 1.2 billion trees from attack by Asian long-horned beetle is $669 billion. Estimates were based upon losses accrued to data.
- Economic impact by purple loosestrife in 19 Eastern and Northcentral States was estimated to be $229 million annually because of decreased value of wetlands, hay and pasture, fur harvest, migratory bird hunting, and wildlife observation and photography.
RANDY C. DYE, West Virginia Forester, President, National Association of State Foresters
Forested landscapes cover approximately one-third of the total land area of the United States, including 100 million acres in urban environments. Every American benefits from forests, whether in the form of wood products for construction or paper, neighborhood amenities, wildlife habitat, carbon sequestration, clean water and air, and even our spiritual well-being. Many Americans’ jobs are linked to trees. The U.S. forest products industry employs nearly 900,000 people; it is among the top 10 manufacturing sector employers in 47 States.
- Invasive species know no boundaries; they span landscapes, land ownerships, and jurisdictions. The damage they cause costs the American public an estimated $138 billion each year, which makes them a significant drain on the national economy.
- Private landowners and small communities are some of the hardest hit by invasive species infestations.
- Invasive species can be exceptionally damaging in urban environments where ecological systems are already stressed. Invasive species threaten the quality of life and the property values of millions of metropolitan residents across the country.
- Currently, 42%—400 of 958—of the plant and animal species listed by the Federal Government as threatened or endangered have been negatively affected by invasive species.
- Invasive species populations have depleted water supplies, poisoned wildlife and livestock, and directly impacted thousands of acres of native forests and rangelands.
- Public recreational opportunities and experiences have become severely de graded by rapid infestations of invasive species, in many cases hampering access, reducing recreational quality and enjoyment, and decreasing the aesthetic values of public lands
Some of the most damaging Invasive species include Asian Long-horned Beetle, Emerald Ash Borer, Gypsy Moth, Sudden Oak Death, Hemlock Woolly Adelgid, and Cogon grass. Municipal governments across the country are spending more than $1.7 billion each year to remove trees on city property killed by these pests. Homeowners are spending $1 billion to remove and replace trees on their property and they are absorbing an additional $1.5 billion in reduced property values.
The scope of the impacts of these pests is demonstrated by a brief description of the threats they pose:
- The Asian Longhorned Beetle kills trees in 15 botanical families—especially maple and birch which constitute much of the forest reaching from Maine to Minnesota and urban trees worth an estimated $600 billion.
- Emerald Ash Borer occupies more than 200,000 square miles in 18 States. More than 200 million ash trees in the Plains States and additional trees in the South are at risk to this pest. Homeowners and municipalities collectively will pay more than $10 billion over the next 10 years to remove dead ash trees that would otherwise fall and could cause property damage or even loss of life.
- Hemlock Woolly Adelgid has killed up to 90% of hemlock trees in the Appalachians from Georgia to Massachusetts. Loss of hemlock groves threatens unique ecosystems and watersheds.
- Goldspotted Oak Borer has killed up to 80,000 California live oak and black oak trees in San Diego County in less than 15 years. The insect threatens oaks throughout California, including close to 300,000 oak trees growing in greater Los Angeles and Yosemite Valley.
- Sudden Oak Death affects 143 different plant species and continues to spread in California’s 14 impacted counties as well as Curry County, Oregon. In 2012 alone, nearly 400,000 trees were lost to Sudden Oak Death in California.
Some examples of plants and plant pests that move in interstate and foreign commerce that have become problems for State inspection, quarantine, agriculture and natural resource authorities are:
There are numerous examples of high priority pests arriving via foreign commerce through airport and harbor hubs. Wooden pallets, used in transporting goods have been especially problematic in introducing wood borer insects (e.g. Asian Long- horned Beetle, Emerald Ash Borer). These pests are now being spread through a variety of local pathways, with firewood as a major vector. The National Association of State Foresters (NASF) has encouraged the U.S. Department of Agriculture (USDA) to move expeditiously to provide a standardized treatment and certification procedure for the interstate movement of all firewood. The firewood industry is largely unregulated, with little or no national regulatory guidelines outside of pest specific quarantine areas and states. This lack of Federal regulation has led many States to seek or pass their own firewood regulations for specific pests.
Cogon grass, a noxious weed infesting pastures and forests first appeared in Alabama as an escape from orange crate packing in 1912. It was intentionally introduced from the Philippines into Mississippi as a possible forage in 1921 and then introduced into Florida in the 1930s and 1940s as a potential forage and for soil stabilization purposes. It now extends as far north as South Carolina and west to Texas.
Some examples of the associated costs to States for invasive species that have arrived via interstate and foreign commerce and then become established in States are:
The Asian Long-horned Beetle kills trees in 15 botanical families—especially maples and birches which constitute much of the forest reaching from Maine to Minnesota and urban trees worth an estimated $600 billion. Emerald Ash Borer occupies more than 200,000 square miles in 18 States. More than 200 million ash trees in the Plains States and additional trees in the South are at risk to this pest. Homeowners and municipalities collectively will pay more than $10 billion over the next 10 years to remove dead ash trees that would otherwise fall and cause property damage or even loss of life.
JASON FEARNEYHOUGH, Director, State of Wyoming, Department of Agriculture
Wyoming began its battle with invasive species in 1895 with its first noxious weed law targeting Russian thistle, or what many of you may recognize as the western tumbleweed. At that time, homeowners were limited in their ability to identify the plant and lacked the resources to control the spread of the species. This made it easy for Russian thistle to establish itself throughout the State and the West in spite of the legislature’s well intended efforts. While the law didn’t stop the Russian thistle, it created the foundation for the State’s current weed and pest program. Today, we are able to assist land owners and managers
Because of these programs, the State has eradicated Yellow starthistle (a toxic plant that covers more than 12 million acre in California) and we have kept our waterway clear of Eurasion watermilfoil and the invasive quagga mussel.
This is no longer just an agricultural issue. We have a broader understanding of the impacts these species play on our ecological systems, communities, recreation, and human health.
Teton County Wyoming is situated in the northwest corner of the State and it is approximately 3 million acres in size. Within its boundaries, the majority of land is managed by Federal agencies who oversee Yellowstone National Park and Grand Teton National Park, the National Elk Refuge, and the Bridger Teton National Forest. The county’s natural resources draw in millions of tourist annually with visitors from all corners of the world who are potentially bringing noxious weed seeds or non-native insects in their luggage, as hitchhikers on their cars, or as food.
A good regional example of insufficient on the ground support is cheatgrass. Wyoming and many Western States have been working diligently to avoid the listing of the sage-grouse as an endangered species and a primary threat to the species is sage brush degradation due to invasive grasses. Cheatgrass matures quicker then native grasses, is highly susceptible to fire and recovers from fire quicker than native grasses. Sage brush communities historically experience wildfires on a 50 year or more cycle, but cheatgrass can reduce that cycle to 5 years or less which makes it difficult for native sagebrush to re-establish. Simply stated, with no sagebrush there is no sage- grouse.
These examples are based on my experiences as Director of the Wyoming Department of Agriculture, but the issue of lacking resources for invasive species in not limited to my State or the West. Each State has its own set of invasive species issues and management needs. In the Southeast it may be giant African snail or Burmese python; in the Midwest it may be Asian carp or Asian longhorn beetle; in the Southwest it may be feral pigs or fire ants. Looking at these few examples, it’s easy to see how invasive species are costing the United States nearly $120 billion in losses annually. This includes the litany of new invasive plants, insects, and animals USDA–APHIS works to stave off at our harbors and ports each year.
Some examples of plants and plant pests that move in interstate and foreign commerce that have become problems for State inspection, quarantine, agriculture and natural resource authorities.
Many of the invasive species Wyoming deals with were introduced through intra-State or foreign commerce. Wyoming lists 25 plant species as State priority weeds. Some of these plants such as Dalmatian toadflax and Russian olive were deliberately introduced as ornamental plants or trees and have escaped cultivation. Some weeds and pests such as Hoary cress, cheatgrass and emerald ash borer were introduced through packing materials. Other weeds such Russian knapweed and quackgrass likely made their way into the United States through contaminated seed. Many of the aquatic invasive species such as quagga mussels and Eurasian watermilfoil were likely introduced through ballast water discharge or through the aquarium trade.
According to the Hawaii Department of Agriculture they share some similar invasive species issues, in addition to some State specific concerns. They noted varroa mites which were accidentally introduced on the island of Oahu in 2007 from California. The varroa mites have been a significant issue for the contiguous United States since 1987. The introduction to Hawaii is notable as prior to 2007 the State represented a unique location within the United States to produce honey bees without the threat of varroa mites. Some of the more State-specific issues Hawaii deals with include little fire ants and coqui frogs introduced through imported plants, and siam weed and fireweed that were likely introduced through contaminated seed. Little fire ants and coqui frogs are also present in Florida, but are not currently found throughout the contiguous States.
Some examples of the associated costs to States for invasive species that have arrived via interstate and foreign commerce and then become established in States:
The costs of invasive species are staggering from the impacts side. The following is a small collection of the economic impacts from various invasive species.
- Leafy spurge costs producers and taxpayers an estimated $144 million/year in just four States alone (MT, WY, ND and SD).
- It is estimated that $16–$44 million dollars of hydropower generation is lost annually due to the salt cedar invasion in the United States.
- Purple loosestrife is responsible for $45 million/year in agricultural losses for the United States.
- Colorado wheat farmers estimate loses from cheat grass and jointed goatgrass to be near $24 million annually.
- S. agriculture loses $13 billion annually in crops from invasive insects, such as vine mealybugs.
- An aquatic invasive plant, Eurasian watermilfoil, reduced Vermont lakefront property values up to 16% and Wisconsin lakefront property values by 13%. In Wyoming, the local Weed and Pest Control Districts collectively spend over $15 million annually for the management of invasive species. Besides direct management, this includes salaries, equipment and other administrative costs.
- The State of Wyoming also allocates an additional $350,000 for the management of invasive weeds and another $1.5 million annually for the management of the invasive vector-borne disease West Nile virus.
- The Wyoming Game and Fish spends $426,000 annually on the inspection of boats for aquatic invasive species.
None of these figures include the costs associated with State quarantines, nursery stock inspection and seed inspection programs that assist in preventing the introduction of new invasive species in Wyoming.
JAMES D. OGSBURY, Executive Director, Western Governors’ Association
Aquatic and terrestrial invasive species are causing extensive damage across western landscapes, coastal areas and Pacific Islands—and have been doing so for some time. In California alone, over 1,000 non-native species have been identified. All over the region, invasive species are harming natural environments and habitat, recreational uses, shore and marine uses, industrial and municipal uses, grazing, and timber harvests.
Invasions of non-native species are resulting in: Decreased biodiversity of native plants, birds, reptiles, and mammals; Increased vulnerability of native species, some of which are endangered and threatened species; Electrical power outages and disruptions; Physical disruption of water supply systems and increased flood damage; Increased wildfire severity (especially from non-native grass); Reduced value of Federal, State and private lands; and Economic harm to communities.
Let me illustrate the Governors’ concerns with several specific examples of invasive species that are now creating challenges for the West: Aquatic Mussels Aquatic invasive species (such as zebra and quagga mussels) are spreading into more western water bodies each year. Western States are on high alert to contain, control, and prevent their proliferation.
The most common sources for the introduction of these species are recreational watercraft and materials sold by aquatic plant and animal suppliers.
Invasion of these mussels result in impairments to water supplies for drinking, energy production, and irrigation.
The economic consequences are severe. For example, the operators and customers of large power plants and water users are spending millions of dollars to clean out zebra mussels from water facilities and additional funds to retrofit those facilities to prevent future invasions.
In addition, native fish and wildlife habitat are negatively impacted when these species become established in streams, lakes, estuaries and other water bodies. Western States have committed significant resources to man watercraft inspection and decontamination stations for invasive species, but this tactic cannot be the only line of defense.
California currently dedicates over $7 million annually to prevent the spread of quagga and zebra mussels into and within State. Decontaminating quagga/zebra mussel fouled watercraft at their source, especially federally managed water bodies, such as Lake Mead National Recreation Area, is essential, or we will continue to witness the spread of quagga and zebra mussel to new areas in the Western United States.
These growing costs do not include local reservoir prevention program or control expenses for water agencies in southern California, including the Metropolitan Water District, which currently spends millions of dollars annually to treat infested Colorado River water. Interception—whether at the source or at the borders—is critical for California, where water project control costs can run as high as $40 million dollars annually if mussels infest the system.
Cheatgrass is an aggressive invader of ponderosa pine, mountain brush, and other rangeland and forest areas in the West. Its ability to rapidly grow, reproduce and overtake native grasses makes it especially troublesome on ranges, croplands, and pastures. Where it becomes dense and dominant, cheatgrass can make wildfires even more severe because they burn easily. After a wildfire, cheatgrass thrives and out-competes native shrubby seedlings such as antelope bitterbrush. Cheatgrass can also diminish recreational opportunities, reduce available forage, degrade wildlife diversity and habitat, and decrease land values.
In California, invasive aquatic plants, such as water hyacinth and other invasive plants have proliferated to the point that they obstruct navigation and create hazards for boats and other watercraft; impair recreational uses such as swimming, fishing, and hunting; damage water delivery and flood control systems; alter water quality; and degrade the physical and chemical characteristics of fish and wildlife habitat. California’s aquatic weed control activities cost over $6 million annually.
The National Invasive Species Council defines an invasive species as ‘‘an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.’’ The rapid spread of invasive species remains one of our country’s biggest environmental problems, a situation complicated by the sheer number of invasive species, lack of a coordinated and comprehensive effort to prevent introductions, monitor and survey for new introductions, and the remarkable ability of invasive species to adapt, reproduce and ultimately overtake entire ecosystems.
Invasive species are a global problem. The annual cost of impacts and control efforts equals 5% of the world’s economy. The U.S. Environmental Protection Agency estimates the country spends at least $138 billion per year to fight and control invasive plant and animal species, such as the emerald ash borer beetles that have destroyed millions of trees in the East and Midwest. Invasive species influence the productivity, value, and management of a broad range of land and water resources in the West, ultimately limiting the direct and indirect goods and services these ecosystems are capable of producing.
Over 100 million acres (an area roughly the size of California) in the United States are suffering from invasive plant infestations.
On a scale of biodiversity destruction, the EPA reports that invasive species rank second only to urban development. Invasive species have been identified by the Chief of the U.S. Department of Agriculture Forest Service as one of the four significant threats to our Nation’s forest and rangeland ecosystems.
The Western Governors recognize that the spread of invasive species results from a combination of human behavior, susceptibility of invaded environments, and biology of the invading species. These characteristics are not dictated by geopolitical boundaries, but rather by ecosystem-level factors, including climate change, which often cross State borders. Scientists and land managers across the West have expressed the need to develop a strategy for more aggressive invasive species prevention, early detection, and management.
Invasive species have significant negative economic, social, and ecological impacts which include, but are not limited to:
- Reduction of the value of streams, lakes, reservoirs, oceans, and estuaries for native fish and wildlife habitat;
- Degradation of water resources for human uses including drinking water, energy production, irrigation systems and other water uses;
- Decreased real estate property value and increased costs of property development;
- Detraction from the aesthetics and recreational value of wildlands, parklands, and other areas;
- Degradation of ecosystem functions and values, including populations of desirable species;
- Reduction of the yield and quality of desirable crop and forage plants that are important in production of our food supply;
- Reduction of native biodiversity, resulting in a growing number of threatened, endangered and extinct species (Note: invasive species have contributed directly to the decline of 42% of the threatened and endangered species in the United States);
- High cost of control;
- Reduction of preferred native vegetation important to native fish and wildlife as well as livestock.
Aquatic invasive species such as the zebra mussel, quagga mussel, and Eurasian water milfoil are spreading into more western water bodies each year.
DEBRA HUGHES, Executive Director, New Mexico Association of conservation districts
New Mexico is the Land of Enchantment with diverse ownership and uses. Forty percent of our land is owned by the Federal Government—predominately by U.S. Forest Service (USFS) at 20% and the Bureau of Land Management (BLM) at 17%; 17% is owned by the State; 10% by the tribes; and 33% by private landowners, but most ranches in the West include ownership and management of private, State and Federal land. NM land uses include ranching and agriculture, oil and gas, and recreation, to name a few. We have diverse wildlife habitat from deserts to mountains; home to deer and elk and much more, including several prominent candidate species such as the Dune Sage Lizard and the Lesser Prairie Chicken.
Specific projects Restore New Mexico has been responsible for include Salt Cedar restoration work along the Delaware River, Creosote Restoration in Last Chance Canyon, Sagebrush and Juniper treatment south of Cuba, New Mexico, reclamation of the Sulimar Oil Field, Henery Tank Mesquite treatments, and Sagebrush shaving adjacent to the Taos Field Office.
Steven A. Horsford, Nevada. Invasive species are a growing problem across millions of acres of Federal land. The spread of invasive species is costing billions of dollars and negatively impacts agriculture, commerce, water quality, and wildlife habitat. Invasive species monitoring, control, and eradication is time consuming and expensive. We can probably use our resources better. In my home State of Nevada, we have massive invasive species issues, the worst being the invasion of the quagga mussel. Cheatgrass and other noxious weeds are also increasing fire risk and impacting sage grouse habitat.
Cynthia M. Lummis, Wyoming. Invasive species, like cheatgrass, have great implications for wild fires and Wyoming’s efforts to prevent the listing of the sage grouse, a huge issue for us right now. So, any solution in a State like Wyoming because of the tremendous amount of Federal land ownership, has to involve an effective Federal commitment.