The first-line of defense and the most cost-effective
strategy against invasive species is preventing them
from invading and becoming established in the first
place. Once an infestation becomes well-established,
management is expensive and eradication is difficult
and unlikely. One of the most important components
of prevention is the detection of individual
plants or small groups of plants after seed germination.
The second is eradication before they produce
seed or develop an established root system. According
to a 1995 survey, very few DOTs feel they have developed
and implemented systems for prevention, detection,
analysis, control, and management.[N]
Eleven DOTs, just over a quarter of respondents, said
they had mapped or were currently tracking/monitoring
areas of infestation as part of efforts to prevent
the spread of invasive species.[N]
A similar number had developed policies and procedures
to support control efforts and/or implemented integrated
roadside vegetation management plans, statewide or
by district.[N]
Six DOTs (15% of respondents) said they are reviewing
the ROW and treating annually for control of invasive
species.[N]
Early Detection, as applied to invasive species,
is a comprehensive, integrated system of active or
passive surveillance to find and verify the identity
of new invasive species as early after entry as possible,
when eradication and control are still feasible and
less costly. It may be targeted at areas where introductions
are likely, such as near pathways of introduction,
and sensitive ecosystems where impacts are likely to
be great or invasion is likely to be rapid.[N]
After invasive species become established, they often
grow deeper root systems and may reproduce by rhizomes
as well. Control after weeds have gone to seed may
begin a long process, since many seeds are viable for
years. Control of non-plant species requires equally
attentive action, and may reach out to law enforcement,
recreational users, and travelers, especially aquatic
vehicles that may carry infested water from one location
to another.
Focusing resources on preventing and detecting new
invasions, to the extent possible, can be far more
cost-effective than containing existing populations.
As the National
Invasive Species Action Plan notes, "[e]ven
the best prevention efforts cannot stop all introductions.
Early detection of incipient invasions and quick, coordinated
responses are needed to eradicate or contain invasive
species before they become too widespread and control
becomes technically and/or financially impossible.
Populations that are not addressed early may require
costly ongoing control efforts."
The remainder of this section focuses on Early Detection
and Rapid Response (EDRR), identification of aspects
of operations that spread invasive species, roadside
inventory, risk assessment, priority setting, and information
management.
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| 9.3.1
Assessment and Management |
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Management of invasive alien species generally
includes:
- Initial assessment of the situation
- A process of identifying the species of highest
priority for a management program
- Detailed information on methods for eradication,
containment, control, and mitigation
- An introduction to monitoring approaches
- Identification of principal approaches to the project
- Activities to secure resources
- Stakeholder commitment and involvement
- Training in control methods
The first step of a management program is to assess
the current situation by determining the management
goal, the extent and quality of the area being managed,
the invasive target species affecting the area, and
the native species threatened. The management goal
should be the conservation or restoration of intact
ecosystems that support the delivery of ecosystem services
and cost-effective maintenance of the area. Eradication
and control options need to be evaluated on the basis
of the likelihood of success, cost-effectiveness, and
any potential detrimental impacts.
Prioritization of invasive species control projects
takes into consideration the extent of the area infested
by the species, its impact, the ecological value of
habitats invaded, the difficulty of control, and management
costs. Species with the highest priority would be those
known or suspected to be invasive but still in small
numbers, species which can alter ecosystem processes,
species that occur in areas of high conservation value,
those imposing or with the potential to impose high
costs on the DOT, and those that are likely to be controlled
successfully.
Eradication, containment, and control are all approaches
to management of populations of invasive species. When
prevention measures have failed, an eradication program
is considered to be the most effective action, because
of the opportunity for complete rehabilitation of the
site and long-term minimization of costs. Since eradication
programs can be initially costly and require full commitment
until completion, the feasibility of this approach
requires careful consideration. Eradication has been
achieved using mechanical, chemical and biological
control, as well as habitat management. These methods
are discussed in detail in Chapter 4: Construction
Practices for Environmental Stewardship.
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| 9.3.2
Identifying Major Pathways and Managing Risk |
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The most common approach for prevention of invasive
organisms is to target individual species. A comprehensive
approach also targets major pathways that lead to harmful
invasions and manages the risks associated with these.
While some have argued that certain pathways, such
as ship ballast water, have already been used for centuries,
current attention to control is still important. Establishment
rates can vary over time. For example, with faster
transport times, some invasive species can establish
in new environments more easily now. Climatic changes
and changes in disturbance in the area of introduction
(e.g., construction opening new areas of land or salinity
and nutrient changes in bays) also affect an area's
susceptibility.
Pathways for introduction of invasive species are
both intentional and accidental introductions. Most
plant and vertebrate species introductions have been
intentional for various reasons, e.g. plants as ornamentals
or for erosion control, mammals as game, birds for
enjoyment, fish for sport fishing. In contrast, most
invertebrates (including marine organisms) and microbe
introductions have been accidental, often attached
to other species introduced intentionally. Often agricultural
weeds have been introduced as contaminants of crop
seeds, whereas most of the environmental weeds were
purposefully planted as ornamentals, for soil stabilization,
or for firewood. Education is a key component of successful
prevention and management methods. DOTs, weed management
areas, and federal agencies have roles in informing
the public why prevention measures are taken and what
impact failure can cause.[N]
Identifying Aspects
of DOT Operations that Promote Invasive
E.O. 13112 mandates a risk-based approach, including
consideration of the likelihood that an invasive species
will establish and spread, as well as the degree of
harm it could cause. To do this, it helps to start
with a master list of the DOT's work activities that
may inadvertently promote the spread of invasive; a
risk assessment identifies the most significant issues
and helps decide where to focus. A few DOTs are identifying
infestations on-site for treatment before ground disturbance,
over multiple years if necessary. Increasingly, measures
are being taken to conserve valuable topsoil, instead
of having it collected and sold by contractors, leaving
deficient soils more vulnerable to infestation by invasive
species. DOTs are checking and treating permanent water
control for West Nile Virus and considering inadvertent
creation of such environments as part of current planning
processes.
Identification of aspects of operations that may
impact the environment is a step in development of
a system to manage environmental impacts, often called
an Environmental Management System (EMS). In an EMS,
the transportation agency identifies environmental
aspects of its activities, products, or services that
it can control and over which it can be expected to
have an influence, to determine those which have had
or can have significant impacts on the environment.
With respect to invasive species and other environmental
impacts, the DOT can then prioritize pathways and controls
according to significance, available funding, risk,
or any other factors the DOT deems important.
While research has indicated that off-road vehicles
are among the largest offenders in transport of seeds
of invasive species, construction projects, transportation
systems, spraying and mowing operations can inadvertently
spread invasive as well. The following are just a few
common mechanisms:
- Use of forage mulches that have not been certified
weed-seed free mulches and other erosion control products.
- Planting of species now controlled as invasive
for erosion control purposes, including aggressive
sweet clovers, alfalfa, smooth brome, trefoil, and
perennial rye.
- Placement of spoil or importation of topsoil contaminated
with invasive, such as ragweed, thistles, and sweet
clovers.
- Ill-timed maintenance disturbances like blading,
mowing, ditch dredging, and bare-grounding, which
have been known to increase invasive.
- Indirect mechanisms such as drainage flows, wind,
vehicles, people, and wildlife.
- Movement of construction equipment from a weedy
site to a non weedy site, which can transport undesirable
seeds.[N]
DOT earthmoving, erosion control, water quality,
wetland restoration, endangered species protection
activities, landscaping, snow storage, utility line
and signage placement, volunteers, recovery zone maintenance,
and other maintenance and operations activities all
affect invasive species and native habitats. Best management
practices (BMPs) are used to reduce the introduction
or spread of invasive species.
The spread of invasive species caused by sub-standard
vegetation or revegetation and the transport of weed
seeds by vehicles are particularly well documented.[N]
An Australian study found that approximately half of
cars were carrying seeds.[N]
Exotic species cover and the number of exotic forb
species decreased as distance from roads increased,
particularly on certain soil types (non-serpentine
soils in particular).[N]
Most DOTs (26 states, 65% of respondents) are not
formally identifying aspects of activities that may
impact/promote invasive species. Some DOTs said they
are already "very cognizant of some of the detrimental
activities and need to incorporate steps to minimize
spread through BMPs." Nine DOTs (23% of respondents)
are explicitly identifying aspects or risk areas. In
Arizona and New York State DOTs, at the district level,
engineers and supervisors are identifying activities
such as mowing, blading and cut cleaning that promote
or spread invasive species and devising BMPs to reduce
these impacts.
DOT Example of Environmental
Aspect/Risk Identification: NSW RTA Assessment of
Construction, Operation, and Maintenance Activities
The New South Wales, Australia, Roads and Traffic
Authority (RTA) undertakes environmental impact assessments
for its construction, operation, and maintenance activities,
in addition to project development. The RTA has committed
to addressing environmental aspects in all of its activities
and to continuously improving the authority's environmental
performance. The RTA-wide environmental management
system ( EMS) has been a primary vehicle for accomplishing
this commitment. It "provides a structured management
system to achieve and demonstrate our environmental
performance."[N]
The RTA prepares a Review of Environmental Factors
to identify and consider environmental impacts, which
may prompt development and/or implementation measures
to address them.
Standard maintenance activities are assessed on a
regular basis, usually annually.[N]
Other maintenance activities are assessed in a similar
way to construction activities.[N]
For maintenance by contract, requirements for environmental
impact assessment are to be incorporated in contract
requirements and reviewed by the RTA.[N]
RTA uses tables to summarize construction and maintenance
activities and associated environmental aspects and
impacts at the NSW RTA. Activities entailing ground
disturbance or use of vehicles and equipment off the
roadway have been particularly identified as potentially
causing the spread of invasive species.
Risk Assessment
A risk assessment process assesses species based
on their perceived risk and potential impact. The objective
of assessment is to predict whether or not a species
is likely to become established and be invasive and
to generate a relative ranking of risk. Entire pathways
may also be analyzed for risk. This may be a more efficient
procedure where many possible species and vectors are
involved. Though the lack of knowledge and ability
to predict consequences may lead to substantial reliance
on assumptions, risk assessment provides a logical
process for gathering, analyzing, synthesizing, comparing
and communicating information, which can improve the
quality of decision-making.[N]
Processes for setting priorities often incorporate
risk assessment. One such process is reviewed in the
following section. Other risk assessment resources
include:
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DOTs set priorities in the hope of minimizing
the total, long-term workload, and hence cost of an
operation, in terms of money, resources and opportunities.
Therefore, invasive species control activities may
be focused on prevention of new infestations and on
existing infestations that are the fastest growing,
most disruptive, and affect the most highly valued
or costly to maintain areas. Also considered is the
difficulty of achieving satisfactory control, giving
higher priority to infestations the DOT thinks most
amenable to control with available technology and resources.
A detailed priority-setting system for weeds is presented
in the Handbook for Ranking Exotic Plants for Management
and Control. [N]
The priority-setting process can be difficult, due
to the need to consider multiple factors. It may be
helpful to group these factors into four categories,
as a filter to identify the worst invasive. This process
is recommended by the Global Invasive Species Program:
[N]
- Current and potential extent of the species on
or near the site. (primary consideration). Under this
category, priorities are assigned to species in order
to first, prevent the establishment of new invasive
species, second, eliminate small, rapidly-growing
infestations, third, prevent large infestations from
expanding, and fourth, reduce or eliminate large infestations.
To do this, assign priorities in the following sequence:
- Species not yet on the site but which are present
nearby. Pay special attention to species known to
be pests elsewhere in the region.
- Species present on the site as new populations
or outliers of larger infestations, especially if
they are expanding rapidly.
- Species present on the site in large infestations
that continue to expand.
- Species present on the site in large infestations,
which are not expanding.
- Current and potential impacts of the
species. The order of priorities under this category
is based on the management goals for your site, but
the following order of consideration may be helpful:
- Species that alter ecosystem processes such as
fire frequency, sedimentation, nutrient cycling,
or other ecosystem processes. These are species that "change
the rules of the game", often altering conditions
so radically that few native plants and animals can
persist.
- Species that kill, parasitize, hybridize or out-compete
natives and dominate otherwise undisturbed native
communities.
- Species that do not out-compete dominant natives
but: prevent or depress recruitment or regeneration
of native species; or reduce or eliminate resources
(e.g. food, cover, nesting sites) used by native
animals; or promote populations of invasive non-native
animals by providing them with resources otherwise
unavailable in the area; or significantly increase
seed distribution of non-native plants or enhance
non-native plants in some other way.
- Species that overtake and exclude natives following
natural disturbances such as fires, floods, or hurricanes,
thereby altering natural succession, or that hinder
restoration of natural communities. In areas of repeated
disturbances, DOTs may want to elevate the importance
of this category.
- Value of the habitats/areas that the
species infests or may infest. Priorities may be assigned
in the following order:
- Infestations that occur in the most highly valued
habitats or areas - especially areas that contain
rare or highly valued species or communities and
areas that provide vital resources.
- Infestations that occur in less highly valued
areas. Areas already badly infested with other pests
may be given low priority unless the species in question
will make the situation significantly worse.
- Difficulty of control and establishing
replacement species. Priorities may be assigned in
the following order:
- Species likely to be controlled or eradicated
with available technology and resources and which
desirable native species will replace with little
further input.
- Species likely to be controlled but will not be
replaced by desirable natives without an active restoration
program requiring substantial resources.
- Species difficult to control with available technology
and resources and/or whose control will likely result
in substantial damage to other, desirable species
and /or enhance other non-indigenous species.
- Species unlikely to be controlled with available
technology and resources.
Species can be ranked numerically (1, 2, 3…n)
or by classifying invasive groups by worst, moderate,
and minor. Invasive species whose populations are decreasing
or those that colonize only disturbed areas and do
not move into (relatively) undisturbed habitats or
affect recovery from the disturbance can be assigned
the lowest priorities.
Other tools and organizations are readily available
to assist DOTs in prioritizing invasive species to
target. NatureServe is
an independent non-profit providing scientific information
and technology, affiliated with the State Natural Heritage
Programs (NHPs). NHPs are often located at state universities
and provide support to other government agencies as
well as The Nature Conservancy. NatureServe developed
an Invasive Species Assessment Protocol, in cooperation
with The Nature Conservancy and the National Park Service.
The criteria develop Invasive Species Impact Ranks
(I-Ranks) at the national and state level. Assessment
criteria include: Ecological Impact, Current Distribution
and Abundance, Trend in Distribution and Abundance,
and Management Difficulty. Species ranked "high" present
a severe threat to native species and ecological communities.
NatureServe plans to evaluate at the U.S. national
level all of the estimated 3,500 non-native vascular
plant species established outside cultivation in the
U.S. using this new assessment methodology. That work
is expected to assist land managers in prioritizing
their work and to support decision making related to
prevention, monitoring, management, research, and identifying
conservation/preservation areas. FHWA and other federal
agencies contributed to development of this system.
Ultimately, the system will:
- Allow management of data through the NHPs' network,
using their software, Biotics and provide access to
data through web site.
- Link non-native species to Ecological Systems.
- Develop more invasive species management information.
- Encourage growth of Early Detection/Rapid Response
pilot project.
- Model potential sites for non-native invasions.
- Identify invasions that are critical to regional
biodiversity resources.
Most DOTs (26 states, 65% of respondents) are not
formally identifying aspects of activities that may
impact/promote invasive species. Some DOTs said they
are already "very cognizant of some of the detrimental
activities and need to incorporate steps to minimize
spread through BMPs." Nine DOTs (23% of respondents)
are explicitly identifying aspects or risk areas. In
Arizona and New York State DOTs, at the district level,
engineers and supervisors are identifying activities
such as mowing, blading and cut cleaning that will
promote or spread invasive species and devising BMPs
to reduce these impacts.
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Prevention involves attention to the most common
vectors of transmission, including contaminated seed,
mulch, or soils; movement of unlearned equipment or
machinery from an invasive weed-contaminated area to
a non-contaminated area; lack of restoration or revegetation
after construction. Prevention depends upon limiting
the introduction of new weeds through:
- Minimizing the disturbance of desirable plants
and soils.
- Maintaining desired plant communities through good
management.
- Monitoring high-risk areas such as transportation
corridors and bare ground.
- Revegetating disturbed sites with desired plants.
- Evaluating the effectiveness of prevention efforts
and adapting plans for the following year.
- Early detection and eradication of small patches
of weeds through regulatory inventory and corrective
action.
Early detection (ED) consists of identifying
and documenting the newly introduced invasive weed
species in an area. Then, rapid response (RR) may
be employed to eradicate new infestations and methods
may be taken to prevent movement to non-infested areas.
Some prevention practices are presented in greater
detail in the section of this document on Cultural
Control Methods.
Early detection of incipient invasions and quick
coordinated responses are needed to eradicate or contain
invasive species before they become too widespread
and control becomes technically and/or financially
impossible. Populations that are not addressed early
may require costly ongoing control efforts. For example,
spotted knapweed (Centaurea biebersteinii) was
introduced to Montana in the 1920s, and by 1988, had
infested more than 4.7 million acres. The economic
impact is approximately $42 million annually.[N]
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Eradication is the elimination of the entire population
of an alien species, including any resting stages,
in the managed area. Efforts at eradication often follow
failure to prevent introduction of invasive species
on construction and other vulnerable sites. Eradication
as a rapid response to an early detection of a non-indigenous
species is often the key to a successful and cost-effective
solution. Once invasive species have spread, eradication
becomes much more difficult and costly, to the point
of being infeasible in many circumstances. Feasibility
should be assessed before attempting eradication. Successful
eradication programs in the past have been based on:
- Mechanical control, e.g. hand-picking of snails
and hand-pulling of weeds. Plants are often best eradicated
by a combination of mechanical and chemical treatment.
- Chemical control, e.g. using toxic baits against
vertebrates and spraying insecticides against insect
pests.
- Biopesticides, e.g. Bacillusthuringiensis (BT)
sprayed against insect pests.
- Sterile male releases, usually combined with chemical
control.
- Physical habitat management controls such as grazing
and prescribed burning.
- Hunting of invasive vertebrates.
If an eradication program is feasible, it is the
preferred choice for action against an invasive non-indigenous
species. Eradication has the advantage of long-term
control, no long-term costs outside of follow up monitoring
and prevention measures, and the opportunity for restoration
of pre-invasion conditions. However, eradication requires
adequate funding and commitment from the stakeholders
involved. Well-established populations and large areas
of infestation may be unsuitable for eradication programs
and may have unintended side effects in addition to
very high cost. For example, in the case of the attempt
to eradicate South-American fire ants in southern states,
the insecticide initially was ingested by wildlife
and cattle. The ant bait subsequently developed also
had non-target effects, and proved to be more effective
against native ant species than the intruder, ultimately
enhancing the populations of the non-indigenous species
due to a decrease of interspecific competition with
the native ant species.[N]
Eradication (or control) of well-established non-indigenous
species, which have become a major element of the ecosystem,
will influence the entire ecosystem. Predicting the
consequences of the successful elimination of such
species, including the synergistic effects, of the
invasive species to indigenous and non-indigenous species
can be difficult but such efforts are important for
avoiding unexpected problems. Cases have been reported
where one invasive species replaces another, following
an effort to eradicate the primary target.
Successful eradication programs tend to involve:
- Small, geographically limited populations of non-indigenous
species are easiest to eliminate. Thus, immediate
eradication is the preferred option for most species
found in early detection surveys. It is crucial that
the early warning program has funds available for
these actions.
- Eradication is considered feasible and adequate
support from stakeholders must be present (this is
easier to achieve on construction sites with existing
contracts or on other land over which the DOT has
control).
- Sufficient funding is secured for an intensive
program (allowing for contingencies) to make sure
that eradication can be pursued until the last individual
is removed. Expectations must be realistic in terms
of the processes required for successful eradication
programs e.g. low visible returns for high investments
late in the program.
- Immigration of the alien species is zero, something
DOTs and contractors can help achieve through vehicle
washing and weed-seed-free mulch requirements. Potential
pathways for the species between infested areas and
the management area must be controlled to prevent
new invasions.
- All individuals of the population are susceptible
to the eradication technique.
- Effective team management and motivation are present.
Teamwork is required to achieve an eradication success,
with a core of field and research expertise to maximize
efficiency and help maintain administrative support.
- A technique to monitor the species at very low
densities, at the end of the program, needs to be
designed to ensure detection of the last survivors.
Organisms that have less obvious stages, which can
survive for long periods, e.g. seed banks of weeds,
need a monitoring period to make sure that eradication
has been achieved.
- Methods to minimize the chances of re-invasion
and early detection of the eradicated species should
it re-establish need to be in place.
- Development and use of field methods are usually
an iterative process since implementation needs to
be monitored and methods may need to be adapted as
conditions change and eradication is approached.
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Containment of non-indigenous invasive species
is a special form of control. The aim is to restrict
the spread of an alien species and to contain the population
in a defined geographical range. The methods used for
containment are the same as those described for prevention,
eradication and control. Containment programs also
need to be designed with clearly defined goals: barriers
beyond which the invasive species should not spread,
habitats that are not to be colonized and invaded,
etc. In order to establish these parameters, a clear
understanding of why the containment is being done
in the first place is necessary; e.g. to protect particular
areas or habitats from invasion or to allow time to
mobilize other control or eradication measures etc.
An important component of a containment program is
the ability to rapidly detect new infestations of the
invasive species both spreading from the margins of
its distribution or in completely new areas, so that
control measures can be implemented in as timely a
manner as possible. These new infestations will initially
be at very low densities so early detection can be
challenging. The invasive species population is suppressed
using a variety of methods along the border of the
defined area of containment; individuals and colonies
spreading beyond this are eradicated, and introductions
into areas outside the defined containment area are
prevented.
A species most likely to be successfully contained
in a defined area is a species spreading slowly over
short distances. The nearest suitable habitat for the
species should be preferably separated by a natural
barrier or an effective artificial barrier. The most
suitable cases for containment are habitat islands
without suitable connections that would allow the easy
spread of invasive species. The spread of alien freshwater
species between different parts of watersheds is a
good example where containment may be possible.
If containment of an invasive species in a well-defined
area is successful, habitats and native species are
safeguarded against the impacts caused by the harmful
alien species outside this area. In cases where eradication
is not feasible and the range of the invasive species
is restricted in a rather isolated area, containment
of the species in that area can be highly effective,
to save other parts even if the species is harmful
in the containment area. Containing a species in a
defined area will, however, need constant attention
and control of the species at the border.
The chances for successful containment of invasive
species are relatively good for species living in freshwater
habitats, e.g. fish spread limited to specific water
catchment areas, unless human activities such as artificial
canals connect catchment areas and allow alien species
to spread between systems.
A related but different approach is exclusion, which
aims to protect a sensitive area against invasive species
by fencing them out. This method often combines eradication,
prevention and fencing techniques. An area of high
conservation value is fenced with an animal-proof fence
and if the invasive species occurs inside, it will
be eradicated. This mainland-islands concept is very
effective in supporting crucial populations of endangered
species, if eradication of the invasive species within
the containment is possible but eradication on a large-scale
is not feasible. Again feasibility and potential unintended
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| 9.3.7
Early Detection and Rapid Response |
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Early detection of non-indigenous species should
be based on a system of regular surveys to find newly
established species. Methods to detect species differ
between taxonomic groups, and their success depends
largely on how conspicuous species are. A drawback
of general surveys is that only well-trained staff
will be able to identify non-indigenous species in
many taxonomic groups.
A 2005 survey found that thirteen DOTs (33% of respondents)
had implemented rapid responses to discovered locations
or patches of invasive species.[N]
Subsets of these had developed Early Detection/Rapid
Response programs. In Illinois and Maryland, District
Landscape Architects notify the local Maintenance Yard,
who responds as soon as they are able. State agriculture
department staff also contacts the DOT when infestations
are observed. Texas DOT utilizes rapid response statewide.
Washington State DOT (WSDOT)'s EDRR efforts utilize
an e-mail list of field staff. DOTs are more likely
to employ early detection and rapid response for species
that are new to the state, to eliminate and avoid new
burgeoning problems (Nevada DOT, New Hampshire DOT,
Oregon DOT). EDRR is also used when a big push is on,
for elimination or reduction of priority species. For
example, Mn/DOT is attempting to eradicate common reed
(Phragmites australis) and Grecian foxglove
(Digitalis lanata ) from the ROW; early
detection and rapid response are employed to "hold
the line" on weed spread into new counties or
from gaining a foothold in new segments of highway.
Caltrans and FHWA have partnered to address exploding
populations of the Sahara Mustard plant in the Mojave
and Sonora deserts, where highway corridors have been
blamed for the weed's spread. FHWA was instrumental
in gathering federal and state partners to work with
Caltrans as part of a rapid response effort and in
funding a workshop. Caltrans is inventorying the plant
on the ROW, which will be used as a benchmark for subsequent
control.[N]
Practices for Effective
Early Detection Programs
A crucial part of early detection is a contingency
plan, which determines the action to be taken when
an alien species is been found. Given the diversity
of potential new incursions, an initial plan will be
rather general. It should summarize the stakeholders
and experts who need to be contacted for a more detailed
action plan. Contingency plans targeted at specific
high-risk species can be very efficient, with an exact
schedule for what to do. For a contingency plan to
work, the equipment needed must be ready at the designated
place and funding must be available for emergency eradication
or control.
Rapid response is a systematic effort to eradicate,
contain or control invasive species while the infestation
is still localized. It may be implemented in response
to new introductions or to isolated infestations of
a previously established organism that is non-native
to the ecosystem. Preliminary assessment and subsequent
monitoring may be part of the response. It is based
on a system and infrastructure organized in advance
so that the response is rapid and efficient.[N]
Looking at models of EDRR from oil spills to fire
to invasive species and diseases, some of the general
features associated of effective EDRR programs are:
[N]
- Strong interest by localities or states in detection
and response.
- Federal leadership through means in addition to
funding (science, training, logistics, and leadership
itself).
- Effective communication of ideas and data with
stakeholders and partners.
- Clear organization, authority and responsibility.
- Exploitation of the most effective means of detection
for the particular system.
- Adequate funding.
- Advance, detailed planning of response organization
and arrangements.
Per research for the National Invasive Species Council
(NISC) on effective EDRR programs, opportunities for
substantial enhancement of passive, early detection
should be exploited:
- For each type of invasive species, explicit consideration
should be given to advantages and opportunities
for passive vs. active detection. Most detection of
invasive species has been passive, and the approach
can be cost-effective when multiple agencies, states,
universities, private groups, and amateur biologists
are involved.
- Anyone who frequently goes into the field and has
some knowledge of biology should be aware of the need
for surveillance and enlisted to help. Publicly available,
user-friendly databases support EDRR efforts. USGS's
Invasive Species Research Center in Fort Collins,
Colorado, working with several partners, has created
a web-based early detection and rapid reporting database
for use by volunteer groups trained to assist in identifying
local invasive species. The database is publicly available
to any agencies that wish to use the data and may
help local mapping and response efforts.
- Effective EDRR requires strong public awareness
and involvement. Many agencies have public education
programs that support EDRR efforts with cross training
and volunteer programs. They have increased public
curiosity and awareness of the environment. For example,
BLM is collaborating with local Coordinated Weed Management
Areas and the state of Wyoming to test the different
elements of FICMNEW EDRR plan for invasive plant.
The concepts of the FICMNEW EDRR plan have been integrated
into all of BLM's actions with over 50 Coordinated
Weed Management Areas in the western U.S.
The Invasive Plant Atlas of New England ( IPANE)
developed "Invasive Alerts" is so that people
can watch for additional incursions. Each alert contains
information on the occurrence, when it was first observed
and the potential threats from the invader. A regional
map to show where these incursions are and photographs
to facilitate identification are included.[N]
IPANE's "Rapid Responders" database is used
to establish teams of experts, once a new incursion
has been reported.
On the other side of the country, the Invaders
Database includes weed distribution records for
five northwestern states, with maps, photos, and biological
information updated regularly. Also, the Western Weed
Coordinating Committee distribution
maps of leafy spurge (Euphorbia esula) and
yellow starthistle (Centaurea solstitialis) in
the western U.S. indicate areas where early detection/rapid
response may help land managers avoid widespread infestations.
Active Detection
- Surveys, Data Collection, and Storage
Active detection may be most effective when targeted
to sites near invasion pathways and to sensitive
ecosystems. NISC compiled the following examples of
successful EDRR practices among NISC cooperating agencies:
[N]
- As little may be known about certain new invasive
species and the correct identification of specimens
is critical, NOAA has developed a list of over 100
taxonomic experts who can identify specimens.
- Monitoring high risk areas and knowing what is
present before an invasive species arrived (baseline
data) are essential to the early detection of new
invasions. ANSTF members have instituted systematic
monitoring programs for aquatic invasive species in
San Francisco Bay, Puget Sound, the Lower Columbia
River, Prince William Sound, Honolulu Harbor, Mobile
Bay, Chesapeake Bay, and Massachusetts Bay. This is
providing baseline surveys of aquatic organisms that
occur in those systems as well as looking for new
invasions.
Though DOTs more often depend on chance sightings
for early detection of invasive species, experts recommend
that early detection of non-indigenous species be based
on a system of regular surveys to find newly established
species.[N]
In general, surveys for early detection are designated
and targeted to answer specific questions quickly and
economically, and give a "yes" or "no" answer.
There are three general types of surveys to consider:
- General surveys for large or conspicuous
animals and plants may be conducted via a "looking
survey." While doing other work, staff should
be vigilant and continually aware of possible signs
of new invaders. The public should be encouraged to
report new sightings as well.
- Site-specific surveys canbe characterized
as general surveys targeted at key sites, e.g. high
value biodiversity areas and areas near high-risk
entry points.
- Species specific surveys. Where specific
threats are identified and prioritized, species-specific
surveys become possible. Frequency and timing of surveys
is important. The potential range of newly arrived
invaders needs to be considered along with the climate
of the region. Survey methods for specific invasive
plants will depend on how easy it is to recognize
the target. If there are similar non-invasive and/or
indigenous species present, then field guides, illustrations
and training may be necessary.
Recommended practices for surveying include:
- Recordkeeping of the species found, both native
and introduced, and the action taken.
- Collection and preservation of specimens. When
local knowledge is not adequate to make an authoritative
identification, material should be sent for specialist
identification. Local and regional museums are a good
starting point for advice on identification of invasive.
- Storage of information in a database, in a standard
format.
DOTs may want to establish and keep up-to-date a
contact list for their specific state or region, including
the names of both institutions and people, what types
of invasive species they might be able to identify
and the methods that should be used for the specimen
collection. Records collected for NEPA evaluations
should be collected in a standard format so that they
form a baseline for further use by the DOT and/or other
agencies. Information about incorporating volunteers
into early detection and monitoring programs may be
found on-line: The
Early Detectives: How to Use Volunteers Against Invasive
Species, Case Studies of Volunteer Early Detection
Programs in the U.S. [N]
Effective Rapid
Response
A crucial part of early detection is a contingency
plan, which determines the action to be taken when
an invasive species is been found. Given the diversity
of potential new incursions, an initial plan is usually
general in nature and notes the stakeholders and experts
who need to be contacted for a more detailed action
plan. Contingency plans targeted at specific high-risk
species can be very efficient, with an exact schedule
for what to do.
For a contingency plan to work, the needed labor
and equipment must be available and accessible. Response
cannot be rapid if elaborate steps are required between
detection and actual attempts at containment or eradication.
Thus the following recommendations were made out of
a national examination rapid response approaches: [N]
- The process for assessment and decision-making
should be flexible and simple, and involve detailed
agreements worked out carefully in advance. This allows
partners to focus on the actual response rather than
on negotiating in an atmosphere of confusion
and ambiguity. Agreements may be numerous
and involve many levels of a hierarchical system
and multiple agencies. They specify what will be done
by whom in any given situation, how leadership will
be identified, how funding will be arranged, and what
preparation will be undertaken. Agreements should
be made at the lowest appropriate levels.[N]
If flexibility in organizational structure is desired,
this can be added after the preplanned organization
is operating.
- Identify an organizational structure for response
in advance, but appoint individuals to positions
as appropriate to the situation while organizing the
response. In interagency responses, a system for assigning
leaders of response organizations (Incident Commanders)
should be identified through agreements made in advance.
The Incident Command System should be adopted as a
standard organizational model for rapid response,
and considered also for long-term, interagency control
projects.
Over a five year period, the Federal Interagency
Committee for the Management of Noxious and Exotic
Weeds (FICMNEW) developed a Conceptual
Design for a National Early Detection and Rapid Response
(EDRR) System for Invasive Plants, after deciding
that EDRR is the most cost-effective and environmentally
sound approach to addressing invasive species. The
proposed National EDRR System for Invasive Plants is
comprised of five elements: 1) Detection and Reporting,
2) Identification and Vouchering, 3) Rapid Assessment,
4) Planning, and 5) Rapid Response.[N]
To facilitate these, the effort plans to develop/identify
lists of target species, list-serves, and contacts
for reporting, and develop generic (broadly applicable)
rapid response protocols and action procedures for
use by local, State, Tribal, and regional partners.
These generic rapid response plans are to be provided
on various invasive plant websites and publications.
They plan to include basic protocols for detection
and delimiting survey data to be collected during treatment
efforts, and methods for post-treatment appraisal surveys.
The initiative also plans to develop and provide technical
expertise on rapid response methods and procedures,
through development of a cadre of scientists and technical
specialists to provide on-site and distant support
on rapid response initiatives and developing, modifying,
or adapting web-based, computer-assisted, decision
support systems to aid land managers in identifying
and developing management options and priorities for
addressing new invasive plants. The effort also seeks
to collaborate with State and national partners to
develop, test, and implement post-response monitoring
protocols and establish a mechanism for reporting post-management
monitoring results and alert network if more action
is needed (adaptive management feedback loop).
Areas in which scientific expertise is likely to
be useful to states are: [N]
- Identification and systematics
- Techniques for surveillance, detection, monitoring,
and related data analyses
- Eradication/control technology
- Biology/ecology with emphasis on risk assessments
These areas of expertise are needed in each taxonomic
group or type of invasive species. NISC's research
also found that the quality of detection and response
activities may be enhanced by providing training and
certification in detection and response.[N] |
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