10.03.18 EAB PacketCITY OF BOULDER
ENVIRONMENTAL ADVISORY BOARD MEETING AGENDA
DATE: October 3, 2018
TIME: 6 pm
PLACE: 1777 West Conference Room, 1777 Broadway
1.CALL TO ORDER
2.APPROVAL OF MINUTES
A.The August 29, 2018 Environmental Advisory Board meeting minutes and
September 19, 2018 Joint Board meeting minutes are scheduled for approval.
3.PUBLIC PARTICIPATION
4.PUBLIC HEARING ITEMS
5.DISCUSSION ITEMS
A.Muni Update (Steve Catanach)
B.Options to Update and Improve Boulder’s Mosquito Management Program (Rella
Abernathy)
6.OLD BUSINESS/UPDATES
7.MATTERS FROM THE ENVIRONMENTAL ADVISORY BOARD, CITY
MANAGER AND CITY ATTORNEY
A.Joint Meeting Debrief (Board)
B.Annual Letter to City Council (Board)
8.DEBRIEF MEETING/CALENDAR CHECK
A.The next meeting is scheduled for Wednesday, November 7, 6-8 pm.
9.ADJOURNMENT
For more information call (303) 441-1931. Board packets are available after 12 pm the Thursday prior to
the meeting, online at www.bouldercolorado.gov.
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CITY OF BOULDER ENVIRONMENTAL ADVISORY BOARD
MEETING GUIDELINES
CALL TO ORDER
The board must have a quorum (three members present) before the meeting can be called to order.
AGENDA
The board may rearrange the order of the agenda or delete items for good cause. The board may not add items requiring public notice.
PUBLIC PARTICIPATION
The public is welcome to address the board (three minutes* maximum per speaker) during the Public Participation portion of the
meeting regarding any item not scheduled for a public hearing. The only items scheduled for a public hearing are those listed under
the category PUBLIC HEARING ITEMS on the agenda. Any exhibits introduced into the record at this time must be provided in
quantities of eight to the Board Secretary for distribution to the board and admission into the record.
DISCUSSION AND STUDY SESSION ITEMS
Discussion and study session items do not require motions of approval or recommendation.
PUBLIC HEARING ITEMS
A Public Hearing item requires a motion and a vote. The general format for hearing of an action item is as follows:
1.Presentations
•Staff presentation (15 minutes maximum*) Any exhibits introduced into the record at this time must be provided in
quantities of eight to the Board Secretary for distribution to the board and admission into the record.
•Environmental Advisory Board questioning of staff for information only.
2.Public Hearing
Each speaker will be allowed an oral presentation (three minutes maximum*). All speakers wishing to pool their time must
be present, and time allotted will be determined by the Chair. Two minutes will be added to the pooled speaker for each such
speaker’s allotted time up to a maximum of 10 minutes total.
•Time remaining is presented by a green blinking light that means one minute remains, a yellow light means 30 seconds
remain, and a red light and beep means time has expired.
•Speakers should introduce themselves, giving name and address. If officially representing a group please state that for
the record as well.
•Speakers are requested not to repeat items addressed by previous speakers other than to express points of agreement or
disagreement. Refrain from reading long documents, and summarize comments wherever possible. Long documents
may be submitted and will become a part of the official record.
•Any exhibits introduced into the record at the hearing must be provided in quantities of eight to the Board Secretary for
distribution to the board and admission into the record.
•Interested persons can send a letter to the Community Planning and Sustainability staff at 1739 Broadway, Boulder, CO
80302, two weeks before the Environmental Advisory Board meeting, to be included in the board packet.
Correspondence received after this time will be distributed at the board meeting.
3.Board Action
Board motion. Motions may take any number of forms. Motions are generally used to approve (with or without conditions),
deny, or continue agenda item to a later date (generally in order to obtain additional information).
•Board discussion. This is undertaken entirely by members of the board. Members of the public or city staff participate
only if called upon by the Chair.
•Board action (the vote). An affirmative vote of at least three members of the board is required to pass a motion
approving any action.
MATTERS FROM THE ENVIRONMENTAL ADVISORYBOARD, CITY MANAGER, AND CITY ATTORNEY
Any Environmental Advisory Board member, City Manager, or the City Attorney may introduce before the board matters which are
not included in the formal agenda.
ADJOURNMENT
The board's goal is that regular meetings adjourn by 8 p.m. Agenda items will not be commenced after 8 p.m. except by majority vote
of board members present.
*The Chair may lengthen or shorten the time allotted as appropriate. If the allotted time is exceeded, the Chair may request that the speaker conclude
his or her comments.
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CITY OF BOULDER, COLORADO
BOARDS AND COMMISSIONS MEETING SUMMARY
NAME OF BOARD/COMMISSION: Environmental Advisory Board
DATE OF MEETING: August 29, 2018
NAME/TELEPHONE OF PERSON PREPARING SUMMARY: Brooke
McKinney, 720-564-2369.
NAMES OF MEMBERS, STAFF AND INVITED GUESTS PRESENT:
Environmental Advisory Board Members Present: Karen Crofton, Miriam Hacker,
Michael SanClements and Justin Brant.
Environmental Advisory Board Members Absent: Jason Vogel.
Staff Members Present: Brett KenCairn, Sandy Briggs and Brooke McKinney.
MEETING SUMMARY:
Alpine-Balsam Area Plan Joint Board Meeting
The board decided that the participation of one board member would be sufficient and agreed to
ask J. Vogel if he would be the EAB’s liaison. M. Hacker agreed to represent the EAB if J.
Vogel cannot. The board determined further discussion was unnecessary.
Joint Advisory Board Meeting on Ecosystems Planning
The board discussed and agreed upon a format and structure for the joint meeting around
identifying ecological concerns, prioritizing and clumping them, small group discussion, and
reporting ideas back to the entire group.
The board emphasized the following:
•There should be a minimum of three groups of four people each.
•A City Council member should be invited to provide an introduction.
•EAB members should facilitate and guide small groups to look for synergies and common
solutions.
•Issues should be able to be addressed locally.
•Identify issues that can be changed, not those beyond our control.
•Ten minute segments should be timed – 10 for prioritization and 10 for each major
concern to be discussed.
1.CALL TO ORDER
Environmental Advisory Board Chair, K. Crofton, declared a quorum and called the meeting to
order at 6:05 pm.
2.APPROVAL OF MINUTES
On a motion by M. Hacker, seconded by K. Crofton, the Environmental Advisory Board
voted 3-0 (J. Brant abstained and J. Vogel absent) to approve the July 18, 2018 and August 1,
2018 meeting minutes.
3.PUBLIC PARTICIPATION
None.
4.PUBLIC HEARING ITEMS
None.3
5.DISCUSSION ITEMS
A.Alpine-Balsam Area Plan Joint Board Meeting
The board reviewed the memo provided by the East Bookend and Alpine-Balsam Area Plans staff
team and their comments are captured in the Meeting Summary.
B.Joint Advisory Board Meeting on Ecosystems Planning
The board discussed and agreed upon a format for the joint meeting. K. Crofton will welcome the
group and provide an overview and purpose for the meeting. J. Vogel will prompt the group to
identify primary ecological concerns and post on a board. While B. KenCairn presents on key
issues regarding ecosystems, M. Hacker and M. SanClements will organize issues into
approximately 2-3 clumps. Small groups, each facilitated by an EAB member, will convene to
prioritize, discuss solutions, and report back to the entire group.
The board then executed this exercise as a dry run.
The board’s comments are captured in the Meeting Summary.
6.OLD BUSINESS/UPDATES
None.
7.MATTERS FROM THE ENVIRONMENTAL ADVISORY
BOARD, CITY MANAGER AND CITY ATTORNEY
8.DEBRIEF MEETING/CALENDAR CHECK
A.The joint board meeting is scheduled for Wednesday, September 19 from 5-8 pm.
B.The next regular meeting is scheduled for Wednesday, October 3 from 6-8 pm.
9.ADJOURNMENT
The Environmental Advisory Board adjourned at 8:00 pm.
Approved:
Chair Date
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MEMORANDUM
TO: Environmental Advisory Board
FROM: Planning and Sustainability
Jim Roberston, Executive Director
Valerie Matheson, Urban Wildlife Conservation Coordinator
Rella Abernathy, Integrated Pest Management Coordinator
Open Space and Mountain Parks
John Potter, Resources and Stewardship Division Manager
Andy Pelster, Agriculture Stewardship Supervisor
Don D’Amico, Ecological Stewardship Supervisor
Will Keeley, Wildlife Ecologist
Marianne Giolitto, Wetlands and Riparian Ecologist
Parks and Recreation
Joy Master, Natural Lands Program Coordinator
Public Works
Joe Taddeucci, Water Resources Manager
DATE: October 3, 2018
SUBJECT: Improving the City’s Mosquito Management Plan
________________________________________________________________________
EXECUTIVE SUMMARY
The City of Boulder’s mosquito management plan was initiated in 2003 in response to a West
Nile virus (WNv) outbreak. Since that time, more is known about mosquito breeding patterns
on city properties, the ecosystem impacts of mosquito control treatments and the risk of WNv
to people. The city’s initial management plan developed protocols to minimize the impacts of
treatments to the environment, but an analysis of data collected since 2003 and new research
shows that refinements can be made that could more effectively manage mosquitoes, while
enhancing and protecting ecosystem health. Proposed changes to the mosquito management
program will address the amount of mosquito activity by lowering negative impacts of
mosquitoes and lowering the risk of mosquito-borne disease by improving wetland ecological
processes and associated ecosystem services, while raising public awareness.
The city’s current mosquito management plan treats all Culex (type of mosquito that can
potentially transmit West Nile virus) larvae at every site with larvicide, regardless of whether
the site is artificial with no ecological value or is part of ecologically-significant wetland
ecosystem. In addition, selected sites in high mosquito activity areas are treated with larvicide
for non-disease transmitting mosquitoes without considering the context of the particular site
or the long-term impacts from mosquito control treatments.
Since the original plan was adopted, multiple studies show concerning effects from mosquito
larvicide treatment at every level of the food web with potentially adverse ecosystem-wide
impacts. Ecosystem management and pest management are not mutually exclusive, and can in
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fact, achieve the same goals by using the inherent strengths of the ecosystem that naturally
limit pest populations. The strategies for a systems or holistic approach to mosquito
management can be achieved by utilizing existing tools for ecosystem management and
applying the knowledge from studies of mosquito biology and mosquito interactions with
competitors, predators and wetland ecological dynamics.
Guiding Question
How might we reduce the negative impact of mosquitoes to people in and around the City of
Boulder with the least amount of environmental impact and the most ecologically-sound
human involvement so that the public feels assured and has confidence that the City of
Boulder is addressing the issues and using resources efficiently?
CORE COMPONENTS OF THIS PLAN
1. Managing mosquito breeding: Reducing mosquito breeding, where appropriate,
while applying treatment solutions that are specific and tailored to each site to
maximize effectiveness;
2.Maintaining or enhancing ecosystem function: A sound and healthy ecosystem is
crucial for environmental sustainability and resilience—functioning ecosystems
support a diverse community of predators that can limit mosquito populations; and
3.Educating, training, and building awareness: Strengthening public awareness and
understanding about mosquito treatments, breeding, and ecological value to further
support the city’s ability to implement and manage an effective program.
PROPOSED BENEFITS AND CHANGES TO EXISTING PROGRAM
1. Building better field protocols to gather site-specific data from each field monitoring
visit to better understand the factors that influence mosquito breeding.
2.Utilize a holistic approach to mosquito larval treatment program. Support ecological
systems overall, using a range of appropriate treatments to help maintain healthy
wetlands and work towards restoring degraded wetlands.
3.Use an adaptive management approach with flexibility to adjust as needed.
4.Redirect savings from program improvements to other areas such as yard inspection
programs and training city operations crews to recognize and mitigate urban mosquito
breeding, which is effective for protecting public health and is better for the
environment.
5.Re-examine and update the original plan’s mosquito breeding site categories to better
reflect each site’s characteristics and choose the most effective management option(s).
6.Increase public education and awareness of the city’s mosquito management protocols
and provide guidance for maintenance of private spaces.
7.Protect city, county and state sensitive species (e.g., northern leopard frog, northern
redbelly dace, grassland-nesting birds), and federally-managed species (e.g., bald
eagle).
Questions for EAB:
1. Does EAB support the staff recommendation and approach for revisions to the city’s
mosquito management program?
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2.Does EAB have any particular issues, concerns or suggestions that you would like to be
addressed during the development and implementation of the new program?
BACKGROUND
With changing climate, habitat destruction/fragmentation, and contamination from pollutants,
including widespread pesticide use, alterations in species composition and range is
transforming the world’s ecosystems with consequences that are yet to be fully understood. A
February 1, 2018 Information Packet memo discusses the planet’s biodiversity crisis and the
city’s Ecological Integrated Pest Management (IPM) Policy that uses a holistic approach that
relies less on direct control methods of individual undesirable species and focuses
predominantly on enhancing biodiversity and ecosystem balance to utilize the natural
processes that keep populations of undesired species low.
An emerging pattern from ecosystem degradation is an increase in pest and disease-causing
species, including mosquitoes and ticks. In some areas of the country, mosquito populations
have increased by as much as 10-fold in the last few decades. According to a recent study, the
main drivers for this increase are anthropogenic – land use patterns, such as urbanization, and
pesticides in the environment.
When the city first developed a mosquito management program in 2002, the environmental
and human health risks of using a suite of pesticides to target mosquitoes at every life stage
were found to be too high, and were not in alignment with the city’s IPM Policy and natural
lands protection guidelines. As West Nile virus (WNv) was moving westward across the
country at that time, it necessitated a thoughtful and effective plan to protect the public health.
The city developed a plan to address the threat of WNv to the public, while protecting the
environment.
Urban areas create artificial environments that breed Culex mosquitoes, the species that can
vector or transmit WNv, and outreach and education programs were initiated to encourage the
public to drain standing water in residential yards and inform residents about the importance
of personal responsibility to avoid mosquito bites.
Potential mosquito breeding sites on open space and natural lands are under city management.
City staff were concerned about applying mosquito control products that could disrupt
wetland ecological balances. Therefore, the city’s program focused on limiting the amount of
larvicide (Bti) applied to wetlands by treating only Culex larvae and leaving non-vector or
nuisance mosquito larvae untreated to reduce Bti application and maintain an important food
source for other animals. In 2007, a nuisance program was added to the WNv management
program in high mosquito activity areas around city recreational facilities and neighborhoods.
For more information about the city’s program, identified gaps, and the approach for the
current program update, please see the April 12, 2018 Information Packet memo.
What Has Changed since the City’s Original Mosquito Management Plan was
Developed?
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Field Data – During the 15 years since the city’s program was adopted, the city has collected
weekly adult mosquito trap data that provides information about location, abundance and the
species of mosquitoes that are present throughout the city. The density and mosquito larval
type (Culex and non-Culex) are collected weekly from each breeding site. Staff and
consultants are analyzing this dataset to determine the patterns of adult mosquito activity,
larval site breeding patterns and modeling the effect of different Bti application protocols on
adult mosquito activity.
Ecosystem Impacts - During the development of the city’s WNv mosquito management plan,
the scientific literature was reviewed to determine the impacts of different mosquito control
products and all were found to have broad and unacceptable impacts, except for the bacterial
larvicide product, Bti. A handful of studies showed non-target impacts and ecosystem
alterations, since Bti kills all aquatic fly larvae, including hundreds of harmless species. Basic
ecological principles would suggest that removal of a large component of the base of wetland
food webs would impact multiple other species. A recent literature review shows wide-
ranging adverse impacts, both direct and indirect, to non-target species and demonstrated
ecosystem-wide impacts from Bti use (see Attachment A). In light of this new information,
staff and ecological consultants have been reassessing larval treatment protocols.
West Nile Virus Risk to People – Our understanding of the epidemiology and risk for WNv
has changed since 2003, which should be used to inform the city’s management approach.
When WNv arrived in the Front Range in 2003, human cases reached epidemic levels and
Boulder County had the highest number of cases in the nation. Cases declined sharply in
2004, and although WNv is now endemic with cases occurring every year, it has not reached
epidemic levels since 2003.
A recent study modeled the driving forces of WNv human cases in 10 states, including
Colorado, under current and future climate scenarios and identified the drivers, which vary
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depending on geographic region. WNv cases in Colorado are primarily driven by two
factors—drought and human immunity. The majority—80 percent—of people who contract
WNv have no symptoms and are unaware they were infected, but then develop immunity. The
authors of this study suggest that population-wide protections from immunity are much higher
than expected and their models predict that it is unlikely that Colorado will experience
another WNv epidemic. However, it’s important to keep in mind that susceptible individuals
can become ill if bitten by an infected mosquito.
Appropriateness of Adult Mosquito Control Contingency Plan – The WNv Mosquito
Management Plan contains provisions for adult mosquito management that includes
spraying/fogging with insecticides in the event of a WNv outbreak. Studies show this
approach is ineffective with potentially adverse effects for human and environmental health.
A WNv outbreak is also unlikely, and if it or another mosquito-borne disease were to reach
concerning levels, staff has outlined a series of escalating risks and associated actions to
reduce human exposure (Attachment B).
Staff Recommendation for Changes to the Program
A team of interdepartmental staff ecologists and ecological consultants have been reviewing
data, scientific literature and assessing ecologically-sound practices to reduce mosquito
activity.
The city’s current program has two major components – 1) larval site monitoring and
larvicide treatment and 2) adult mosquito monitoring and WNv testing.
In addition to refining larval treatment protocols, there are other opportunities to improve
mosquito management. Staff is proposing an adaptive management plan that addresses each
site individually, gathers data to assess adult and larval populations, relevant ecological
parameters, and reviews the data each year to continuously improve the program.
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The following table provides an overview of proposed changes to the program.
Program Component Rationale
Keep
Unchanged
Adult mosquito trapping, monitoring
and WNv testing
Provides valuable information about
overall mosquito activity and WNv
risk
Modify Larval breeding site treatment
− Categorize sites by ecological
quality
− Pinpoint breeding habitat within
each site
− Choose from multiple treatment
options to tailor most
appropriate/effective
management for each site
− Refine existing field treatment
protocols for Bti application
− Develop new protocols for
ecological field technicians to
monitor mosquito breeding,
natural enemy presence, and
other relevant site attributes
Site-specific treatments provide
better mosquito management,
protect biodiversity and can provide
more comprehensive management of
mosquito populations based on
current research and
scientific/ecological principles
Modify Adult mosquito control contingency
plan
The original WNv management plan
allowed for insecticide application
for adult mosquitoes if certain
thresholds were met. The thresholds
have never been met. The potential
harm of adulticide treatments
outweighs the benefit. A chart of
escalating WNv risk and associated
city actions has been created that
addresses risk and protect public
health (Attachment B).
Modify Improve public education and
outreach
− Provide more information about
city operations to increase
transparency and better
understanding about the city’s
program.
− Provide more outreach about the
role of personal responsibility
and actions to reduce mosquito
breeding sites and prevent bites.
− Improve complaint tracking to
help ID potential mosquito
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Program Component Rationale
problem spots and refine
management to more effectively
address.
Add Integrated irrigation management and
infrastructure maintenance strategy
by interdepartmental team
Minimize mosquito breeding sites
caused by irrigation by evaluating
drainage from fields and trails,
modify irrigation water release
schedules where appropriate,
coordinate between departments
responsible for ditch maintenance or
relationships with ditch companies
to better respond to mosquito
breeding issues – both prevention
and responding to problems as they
arise
Add Train urban staff from Parks
Operations and Public Works to
recognize breeding problem spots in
parks, storm water drains and other
public areas
Crews will receive training to report
or manage areas with stagnant water
and respond in the field to drain or
treat with Bti.
Add Develop materials for code
enforcement to provide to private
property owners with standing water
issues.
There is no ordinance to address
standing water on private property.
Code enforcement could provide
educational materials in response to
neighbor complaints about standing
water issues.
Most significant change – larval breeding site assessment and treatment options
Mosquito breeding sites cover a wide range of types from muddy depressions in soil, stagnant
water in containers or storm drains to high quality wetlands. If breeding sites can be
eliminated by inspecting and draining artificial sites, cleaning clogged trash gates in ditches or
managing flood irrigation, this is the quickest and most effective approach. However, sites
with high ecological function can possess built-in pest controlling organisms, such as fish,
predatory insects, birds and spiders that can keep mosquito populations naturally low. Bti
should be used where appropriate, but alternative treatments should first be considered.
Staff is currently assessing the ecological significance of breeding sites and mosquito larval
breeding history to develop a site-specific management plan. Breeding sites fall roughly into
the following categories:
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General Characterization of Mosquito Larval Breeding Types
The most challenging category is 4 – high quality/high breeding sites. Some of these sites
may need to be treated with Bti in the short-term. However, high quality/high breeding sites
are the most susceptible to damage from repeated Bti applications and staff will be exploring
alternative treatments to decrease mosquito breeding habitat and enhance predator
populations.
The following table provides a range of treatment options. Some may be implemented over
time as program changes are evaluated as these treatments are implemented.
Mosquito Treatment Pros Cons
Bacterial larvicide - Bti
(Bacillus thuringiensis
israelensis)
− Effective at killing mosquito larvae
− Less impactful than synthetic
chemical pesticides, surface oils
and methoprene (insect growth
regulator)
− Proven industry standard
− Body of literature shows direct
impacts to non-target organisms,
including amphibians
− Indirect impacts to non-targets
− Ecosystem-wide impacts
− Persistent in sediment
− Spores can be transferred to untreated
sites
− Can replicate
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Mosquito Treatment Pros Cons
− Formulations can contain
contaminants
− Evidence that resistance can develop
in some mosquito species
Predator complexes that
occur naturally
All mosquito life stages are prey items
for many groups of animals in both
aquatic and terrestrial systems.
− Can be highly effective
− Cost-effective
− Part of thriving ecosystem that
provides many other benefits,
including wetland ecosystem
services
− Complies with IPM policy and
integrated ecosystems strategy
− Manages for increases in
distribution and abundance of
sensitive species
− Variable and complex depending on
type of site
− Highly site specific
− Colonization rates vary for mosquitoes
and predator groups
− Requires resources for monitoring and
data analysis
Encouraging predators
by creating habitat or
enhancing existing
wetland health
− Attracting wide variety of
invertebrate and vertebrate species
provides free, efficient pest control
− Provides other important ecological
benefits and services
− Improves biodiversity
− Studies provide guidance for
improving habitat (e.g. plantings to
attract spiders, birds)
− Terrestrial predators reduce adult
mosquitoes migrating from outside
city properties
− Must align with site-specific objectives
− Not appropriate for all sites
− Takes time to implement - would have
to be transitioned over time
Introducing predators as
biocontrol agents
− Option for low or mid-quality
wetlands
− Can rear some biocontrols (e.g.
copepods)
− May be able to purchase
− Potential to transfer from other sites
− Important to source/use native
predators
− No experience using this method
− May need to gather data about a
candidate site before initiating
− Requires tracking and monitoring
− May require special permits
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Mosquito Treatment Pros Cons
Vegetation management
and prescribed burning
− Vegetation management can
decrease harborage for adult
mosquitoes, breeding habitat for
larval mosquitoes and attract
predators.
− Improves invasive species
management and improves overall
biodiversity and habitat quality
− Advances other city site objectives.
− Takes time to learn vegetation
management specifically for mosquito
management
− May not be appropriate for other site
management objectives
Create new healthy
wetlands
− Can control large numbers of both
larval and adult mosquitoes
− Provides other important ecological
benefits and services
− Sequesters carbon
− Provide resilience to reduce impacts
from extreme weather events
− Expensive
− May need to secure water rights - can
be costly, lengthy process
− Must align with other objectives to
justify cost
Filling in artificial
depressions (e.g. wheel
ruts, cattle hoof prints)
− Eliminates poor quality sites that
readily breed mosquitoes
− Reduces Bti application
− Labor-intensive/costly
− Logistically difficult to implement
− At some sites, could adversely impact
surrounding area if near sensitive
habitat
− Depending on cause, may be more
cost-effective to prevent (e.g. herd
management)
− May require permits to fill if in
jurisdictional wetlands
Herd Management − Minimize the overlap of grazing
and flood irrigation to prevent hoof
disturbance of wet soils.
− Cost-effective and preventive
− Reduces Bti application
− Requires coordination with staff,
lessees (water release management,
cattle grazing, etc.)
− In some situations, may not be feasible
− Heavy rain can create same issue as
irrigation
Optimize irrigation
practices
− City staff has worked with OSMP
agricultural lessees to alter water
release and scheduling to decrease
standing water.
− Land and irrigation management
− In some cases, runoff can create good
wetlands, which needs to be balanced
with standing water that becomes a
breeding site
− Can be logistically difficult to
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Mosquito Treatment Pros Cons
practices can be viewed through
the lens of mosquito breeding to
decrease potential breeding sites
− Flood irrigation could be tool to
decrease floodwater mosquitoes by
allowing hatching and then
draining to kill larvae before they
can emerge as adults.
coordinate all players
− Water rights are administered by the
State of Colorado and there are
limitations on what can be achieved
regarding modifying irrigation
schedules and quantities that may
impact mosquito breeding.
Drain artificial breeding
sites
− Train staff to check equipment that
can fill with water and store to
prevent and dump or drain when
holding water
− Train staff to avoid overwatering
and notice when ground,
particularly turf, is saturated
− Check gutters and maintain to keep
clear and flowing
− Train staff to check storm drains
and other areas that could become
clogged and hold water
Requires resources and training.
NEXT STEPS
− Staff and consultants will complete:
Breeding site categorization
Breeding history analysis for individual sites
Completion of field protocols for Bti application and ecological monitoring
− Meet with advisory boards to provide feedback to council from the Environmental
Advisory Board (Oct. 3), Open Space Board of Trustees (Oct. 11) and Parks and
Recreation Advisory Board (Oct. 22).
− Council presentation and direction (Nov. 8)
− Public engagement – Dec. 2018 – Feb. 2019
− Complete Request for Proposal for program components – Feb. 2019
− Hire contractor(s) – March 2019
− Implementation of revised program – April 2019
− Provide council with update after first year of implementation – November 2019
Attachments:
Attachment A: Review of Scientific Literature for Impacts of Bacillus thuringiensis sub-
species israelensis (Bti) for Mosquito Larval Control
Attachment B: Actions for Escalating West Nile Virus Risk
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Review of Scientific Literature for Impacts of Bacillus thuringiensis sub-
species israelensis (Bti) for Mosquito Larval Control
Summary
The larvicide, Bacillus thuringiensis israelensis (Bti), is the most targeted and least toxic product
option for mosquito management. In most situations, Bti is effective at killing mosquito larvae.
However, its use should be limited due to direct toxicity to non-target organisms such as frogs
and harmless and beneficial insects, as well as indirect effects, which can impact ecosystem
function, from water quality to bird reproductive success.
Contaminants have been reported in formulated products, including pathogenic bacteria, toxins
and endocrine disrupting activity. Although Bti resistance is not known to be widespread in
mosquito larvae under field conditions, Bti has been shown to persist in the environment and it
can “recycle” or replicate. Bti spores can be transported to untreated sites by adherence to animal
bodies or through feces and cause potential non-target impacts at these untreated sites.
Bti has its place in mosquito management. Due to the potential for ecosystem-wide impacts,
however, other alternatives such as natural population controls, should be considered before Bti
application—particularly in high-functioning wetlands and natural areas where Bti can disrupt
ecosystem communities.
Background
Bacillus thuringiensis (Bt) is a gram-positive bacterium that forms toxin-containing protein
crystal inclusions. When ingested by susceptible invertebrates, the crystals attack the gut. More
than 67 Bt sub-species have been identified that are targeted to specific insect groups. The sub-
species Bacillus thuringiensis israelensis (Bti) was discovered in 1976 and is toxic to aquatic fly
larvae, including mosquitoes, black flies, craneflies, non-biting midges (chironomids), fungus
gnats, filter flies and others in the sub-order Nematocera. When the Bti crystal inclusions are
ingested by the larva, it binds to the gut, releases toxins, and forms pores that disrupt the tissues
and osmotic balance, killing the insect. See Lacey, 2007 details.
The Bti life cycle has a “sporulation cycle,” that includes vegetative cell division and spore
development. The vegetative phase is the living, replicating component of the lifecycle. Each
vegetative cell divides into two daughter cells. When starved of nutrients, a daughter cell within
the mother cell is walled off into an “endospore.” When the mother cell dies, the spore is
released. These spores are dormant and resistant to drying, heat and other environmentally
adverse conditions. The protein crystals afford protection for the spores and also provide
nutrients for germination when the spores are activated and convert to vegetative cells (Ibrahim
et al., 2010).
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Endospore formation and cycle (Attribution)
Production
Bti is produced by fermentation in large vats using a variety of materials/media that provide
nutrients for the bacteria, which can influence its toxic properties and final formulation. For
instance, some of the nutritional media can remain when the spores are recovered (Lacey, 2007).
A few days before harvesting, nutrients are no longer provided, at which point the bacteria die,
leaving dead cells, crystal proteins, and spores in the fermentation broth. The broth is processed
into formulations of the final Bti product (Valent Biosciences). Additives are typically not
disclosed by pesticide manufacturers and are considered proprietary information, but can include
synergists, surfactants, sticking agents and UV protectants.
The potency is tested from each batch, which is measured in international toxic units or
[ITU]/mg. However, there is no screening for metabolite or microbiological contaminants, and
pathogenic bacteria have been found in Bti preparations (World Health Organization, 2009).
Screening for endocrine disrupting properties is also not conducted on Bti formulations.
However, significant estrogenic properties were found in three of five Bti formulations in
laboratory assays, although it was not detected in field testing. These tests were conducted to try
to determine the source of estrogenic activity in ground water near areas where Bti was applied.
(Maletz et al., 2015).
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3
Other toxic products, in addition to the protein crystals, can be produced by Bti:
During vegetative growth, various Bt strains produce an assortment of antibiotics,
enzymes, metabolites and toxins, including Bc toxins, that may have detrimental effects
on both target organisms and non-target organisms. Beta-exotoxin, a heat-stable
nucleotide, is produced by some Bt subspecies during vegetative growth and may
contaminate the products. Beta-exotoxin is toxic for almost all forms of life, including
humans and the target insect orders (World Health Organization, 2009).
Efficacy
Larvicides are considered the most effective and important component of mosquito control
programs, since treatments can be applied to known breeding sites where mosquitoes are
concentrated, and larviciding prevents the emergence of adult mosquitoes. Bti is also one of the
most targeted and least acutely-toxic product options. Different formulations are designed to
make contact with mosquito larvae in different types of habitats and include powders, liquid
suspensions, granules, tablets, and briquettes. Multiple variables effect the lethality of Bti,
including the insect’s instar (age), density, organic content, temperature, susceptibility of the
target species, etc. (Laurence et al. 2010). Larvae that ingest Bti die rapidly—usually within a
few hours.
Persistence, Proliferation and Resistance
Problems can arise from the use of all insecticide products, whether synthetic, natural or
microbial—broad-spectrum or targeted. As pest managers become more reliant on regular use of
pesticidal products, the pesticide can accumulate in the environment and insects can develop
resistance.
Resistance: Field resistance to Bt sub-species that target beetles or lepidopterans has been
reported and the underlying genetic mechanisms have been studied. The changes in genetic
expression that allow insects to develop resistance have also been examined in mosquito larvae
(Tetreau et al., 2012). Because Bti has four major toxins and additional minor toxins, the
development of resistance is complex and requires the involvement of multiple genes (Bonin et
al., 2015, Ben-Dov, 2014). This is thought to be the reason why resistance is developing slowly
in natural mosquito populations. There are, however, cases in the literature of confirmed
resistance. A high level of resistance to Bti was detected in a population of Culex pipiens in New
York (Ayesa et al., 2005).
Persistence: Insecticides that break down slowly and persist in the environment chronically
expose both target and non-target organisms. Persistent pesticides prolong exposure of the pest,
and if the pest remains susceptible, the pesticide will continue to control it. But long-term
exposure can drive resistance and contribute to undesirable non-target impacts that can alter
ecosystem dynamics. Studies show a range of activity for Bti under field conditions. Although
it’s generally thought that Bti is gradually deactivated and does not persist, several studies show
that it can and does persist and remain toxic. Bti leaves the water column relatively quickly, after
which the spores settle out of the water and bind to the soil substrate or particulates. When the
soil or particulate substrates were stirred and filtered three weeks later, the suspension retained
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4
toxicity (Ohana et al., 1987) A study with simulated field conditions showed Bti residual activity
for 20 weeks (Marcombe et al., 2011). Decaying leaf litter collected from ponds treated with Bti
was found to be highly toxic to mosquito larvae months after application (Tetreau et al., 2012).
Bti spores can persist for months in the environment. The number of treatments, the type
vegetation, and the presence of organic matter are all associated with persistence of the spores.
Change in water level or salinity does not appear to affect spore persistence. “Recycling” or
proliferation is when the spores germinate and return to vegetative growth, replicate, sporulate
and produce toxins. Bti can kill mosquito larvae and then proliferate from their carcasses (Aly et
al., 1984). Pupae can also recycle Bti. Older forth instar larvae that ingested Bti and completed
pupation, later died as pupae from Bti infection and the carcasses of the pupae were found to
recycle Bti (Khawaled et al, 1989).
One study showed no evidence that recycling occurs in sediment or other substrates and found
that mosquito larvae must be present for recycling to occur (Duchet et al., 2013). However
another study found much higher levels of spores in leaf litter than expected from Bti application
alone and the researchers suggest that proliferation is occurring, as well as spore persistence
(Tetreau et al., 2012). Bti has even been detected from untreated sites at high levels in decaying
leaf litter. A high number of viable spores correlated with toxicity of the leaf litter samples to
mosquito larvae. The researchers suggest that the bacteria could be germinating and proliferating
in the natural environment (Tilquin et al., 2008). Spores can be transported to untreated sites by
animals in two ways. The spores can adhere to the bodies of animals or be excreted after
ingestion in the feces. The excreted spores maintain toxic properties and mosquito larvae are
killed when exposed to them (Brazner and Anderson, 1986, Snarski, 1990).
The variability in studies shows that analytical techniques, field conditions, formulations and
many other factors determine the persistence of Bti, and unlike most pesticides, since Bti is a
microorganism, it does have the ability to replicate. This raises concerns about resistance
developing in mosquito larvae, as well as impacts to food webs and habitat quality.
Ecological Impacts
Bti is a biopesticide and it is commonly thought to be safe and non-toxic to vertebrates and non-
target invertebrates. This assumption is based on a number of studies in the past that found no
secondary or indirect impacts from Bti treatments. During that same time period, some studies
did record concerning impacts from Bti. One study measured significant losses in biomass at
sites treated with Bti. In a three-year study, insect densities were reduced by 57 to 83% and
biomass was reduced by 50 to 83% (Niemi et al., 1998). The researchers emphasized the
potential impacts from the magnitude of these losses:
The prevailing knowledge of wetland ecosystems is too limited to fully assess the
ramifications of these declines in aquatic insect communities for other food web
components or for the overall functions of these wetlands. The application of these
insecticides can certainly be viewed as changing the function and structure of these
wetlands because of large reductions in insects, a major component of wetland food
webs. It is difficult to believe that reductions of insect density and biomass in the range of
19
5
50 to 80% would not eventually have major effect on these wetlands. Their ultimate
effects remain unclear.
Direct Ecological Impacts
Several recent studies indicate a wide range of impacts from Bti treatments at all trophic levels of
wetland ecosystems.
Impacts to non-target flies: Bti kills mosquitoes and other aquatic fly larvae from the sub-order
Nematocera. Therefore, it would be expected that populations of non-target flies will be
impacted from Bti use. The non-biting midges, or Chironomidae, are a diverse group of flies and
can make up more than half of the species in wetland systems and dominate flying insects. A
recent study that surveyed male chironomids in Colorado’s Fountain Creek Watershed identified
151 different species (Hermann et al., 2016). Although different studies have shown a range of
impacts to chironomids from Bti application, some have shown no impacts. One found no
difference from Bti treatment for two common chironomid species in natural wetlands (Duchet et
al., 2015). Another study cautioned that toxicity to Bti in chironomids varies greatly throughout
their development and that many studies likely underestimate risk. Toxicity to larvae of
Chironomus riparius was 209 times greater for first instar larvae and 90 times greater for second
instar larvae than the lowest field application rate used in mosquito control (Kästel et al.,2016).
Another study of temporary flooded wetlands found rich biodiversity of chironomid species with
high turn-over between years in these unstable habitats. Bti treatment did not lower species
richness. However, treated sites had a significant difference in species turnover and colonization
dynamics were affected (Lundström et al., 2009). One study showed a significant decrease in the
density of chironomids from Bti treatment (Pauley et al., 2015) and another long-term study in
natural wetlands showed a 78% reduction of chironomid and related aquatic flies in treated areas
(Jakob and Poulin, 2016).
Impacts to non-fly invertebrates:
Although no acute toxicity to Bti was observed, the amphipod, Gammarus lacustris, ingested Bti
and spores were found in its feces. The amount of time that Bti remained in the gut was much
longer than expected. Bti spores were also found in the guts of newborn progeny that were born
at least a week past the last Bti exposure of the parent (Brazner and Anderson, 1986).
Bti is not just toxic to aquatic flies. A review paper listed an expanded host range of species that
are susceptible to Bti that includes terrestrial flies, moths, beetles, nematodes and flatworms
(Ben-Dov, 2014).
Five species of zooplankton or microcrustaceans that coexist with mosquito larvae in coastal
wetlands were exposed to range of Bti concentrations and were examined for acute and chronic
effects. Crustaceans were chosen for this study with a range of different feeding behaviors,
including predators, herbivors, filter feeders and benthic scrapers. As concentrations of Bti
increased and over time, there was a pattern of increasing mortality (Olmo et al, 2016). Another
study found Cladocera (waterfleas) were significantly affected by Bti treatment (Pauley et al.,
2015).
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6
Impacts to amphibians:
Bti is said to be nontoxic to vertebrates. However, recent studies show direct toxicity to tadpoles
(Hyla versicolor). Short-term exposure of tadpoles to Bti affected their locomotion. Compared to
controls, exposed tadpoles spent more time motionless, spent less time swimming and traveled
shorter distances (Junges et al., 2017). When predators (dragonfly larvae) are present, Bti
treatment significantly decreases tree frog tadpole survival (Pauley et al., 2015). Tadpoles
(Leptodactylus latrans) showed dose-dependent sensitivity to Bti and 100% died after 48 hours
of exposure to the highest dose, which is at the top range of recommended field rates. Exposure
to lower doses of Bti induced intestinal damage (See figure below). Changes to enzymes created
oxidative stress, leading to genotoxicity, which could be the cause the intestinal disruption
(Lajmanovich et al., 2015).
From Lajmanovich et al., 2015.
Indirect Effects
The organisms that are directly affected from Bti are members of complex wetland communities
and impacts to one component can have cascading effects that indirectly impact other organisms.
Studies that assess indirect impacts are challenging to conduct. The majority of studies related to
Bti effects look at efficacy for killing mosquito larvae. There are several studies looking at direct
impacts to non-target organisms, but very few on indirect effects or persistence (Poulin, 2012).
Impacts to micro-organisms:
Very low concentration Bti treatment (too low to kill mosquitoes) in freshwater microcosms
caused no measurable impacts to microorganisms, nutrients or suspended particles. Two weeks
after application of high dose Bti, mosquito larval and microorganism density were decreased—
the most abundant bacteria species were suppressed. After 44 days post-treatment, cyanobacteria
was significantly reduced, showing changes in microbial community composition, reduced
nutrients and algae (Duguma et al., 2015).
In a large study of natural wetlands, Bti application increased the density of protozoans by 4.5
times and the taxonomic richness increased by 60%. Mosquito larvae feed on protozoans and
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7
both mosquitoes and protozoans feed on bacteria (Östman et al., 2008).
A study showed that Bti is not directly toxic to phytoplankton. Mosquito larvae feed on
phytoplankton, which decrease in a curvilinear fashion as mosquito density increases. Primary
producers are indirectly impacted when mosquito larvae and related species are killed and
removed from the ecosystem from Bti application (Duguma et al., 2017).
Impacts to macroinvertebrate mosquito predators:
A large-scale, five-year study of adult Odonata (dragonfly and damselfly) monitored richness
and abundance in natural wetlands. A five-fold reduction in abundance and three-fold reduction
in richness was found in Bti-treated sites. This was thought to be due to depletion of food
availability from an 87% reduction of aquatic flies from treated sites (Jakob and Poulin, 2016).
Impacts to vertebrates:
House martins were assessed for three years between control and Bti-treated sites for diet, clutch
size, and fledging survival. Insect prey at untreated sites was mainly spiders and dragonflies.
Prey items were significantly smaller at treated sites and more flying ants were eaten.
Reproductive success was lower at treated sites with decreased clutch size and fledging survival
(Poulin et al., 2010).
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Kästel, A., Allgeier, S., & Brühl, C. A. (2017). Decreasing Bacillus thuringiensis israelensis
sensitivity of Chironomus riparius larvae with age indicates potential environmental risk for
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Lacey, L. A. (2007). Bacillus thuringiensis serovariety israelensis and Bacillus sphaericus for
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Maglianese, Marquz, V.A. Beccaria, A. J. (2015). Toxicity of Bacillus thuringiensis var.
israelensis in aqueous suspension on the South American common frog Leptodactylus latrans
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(Anura: Leptodactylidae) tadpoles. Environmental Research, 136, 205–212.
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Laurence, D., Christophe, L., & Roger, F. (2011). Using the Bio-Insecticide Bacillus
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and Pesticides Exposure and Toxicity Assessment. InTech. https://doi.org/10.5772/17005
Lundström, J. O., Brodin, Y., Schäfer, M. L., Vinnersten, T. Z. P., & Östman, Ö. (2009). High
species richness of Chironomidae (Diptera) in temporary flooded wetlands associated with high
species turn-over rates. Bulletin of Entomological Research, 100(4), 433–444.
https://doi.org/10.1017/s0007485309990472
Maletz, S., Wollenweber, M., Kubiak, K., Müller, A., Schmitz, S., Maier, D., … Hollert, H.
(2015). Investigation of potential endocrine disrupting effects of mosquito larvicidal Bacillus
thuringiensis israelensis (Bti ) formulations. Science of The Total Environment, 536, 729–738.
https://doi.org/10.1016/j.scitotenv.2015.07.053
Marcombe, S., Corbel, V., Yébakima, A., Etienne, M., Yp-Tcha, M.-M., Darriet, F., & Agnew,
P. (2011). Field Efficacy of New Larvicide Products for Control of Multi-Resistant Aedes
aegypti Populations in Martinique (French West Indies). The American Journal of Tropical
Medicine and Hygiene, 84(1), 118–126. https://doi.org/10.4269/ajtmh.2011.10-0335
Niemi, G. J., Hershey, A. E., Shannon, L., Hanowski, J. M., Lima, A., Axler, R. P., & Regal, R.
R. (1999). Ecological effects of mosquito control on zooplankton, insects, and birds.
Environmental Toxicology and Chemistry, 18(3), 549–559.
https://doi.org/10.1002/etc.5620180325
Ohana, B., Margalit, J., & Barak, Z. (1987). Fate of Bacillus thuringiensis subsp. israelensis
under Simulated Field Conditions. Applied and Environmental Microbiology, 53(4), 828–831.
Full text.
Olmo, C., Marco, A., Armengol, X., & Ortells, R. (2016). Effects of Bacillus thuringiensis var.
israelensis on nonstandard microcrustacean species isolated from field zooplankton communities.
Ecotoxicology, 25(10), 1730–1738. https://doi.org/10.1007/s10646-016-1708-9
Östman, Ö., Lundström, J. O., & Persson Vinnersten, T. Z. (2008). Effects of mosquito larvae
removal with Bacillus thuringiensis israelensis (Bti) on natural protozoan communities.
Hydrobiologia, 607(1), 231–235. https://doi.org/10.1007/s10750-008-9387-z
Paul, A., Harrington, L. C., Zhang, L., & Scott, J. G. (2005). Insecticide resistance in Culex
pipiens from New York. Journal of the American Mosquito Control Association, 21(3), 305.
https://doi.org/10.2987/8756-971x(2005)21[305:iricpf]2.0.co;2
Pauley, L. R., Earl, J. E., & Semlitsch, R. D. (2015). Ecological Effects and Human Use of
Commercial Mosquito Insecticides in Aquatic Communities. Journal of Herpetology, 49(1), 28–
35. https://doi.org/10.1670/13-036
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Poulin, B. (2012). Indirect effects of bioinsecticides on the nontarget fauna: The Camargue
experiment calls for future research. Acta Oecologica, 44, 28–32.
https://doi.org/10.1016/j.actao.2011.11.005
Poulin, B., Lefebvre, G., & Paz, L. (2010). Red flag for green spray: adverse trophic effects of
Bti on breeding birds. Journal of Applied Ecology, 47(4), 884–889.
https://doi.org/10.1111/j.1365-2664.2010.01821.x
Snarski, V. M. (1990). Interactions between Bacillus thuringiensis subsp. israelensis and Fathead
Minnows, Pimephales promelas Rafinesque, under Laboratory Conditions. Applied and
Environmental Microbiology, 56(9), 2618–2622. Full text.
Tilquin, M., Paris, M., Reynaud, S., Despres, L., Ravanel, P., Geremia, R. A., & Gury, J. (2008).
Long Lasting Persistence of Bacillus thuringiensis Subsp. israelensis (Bti) in Mosquito Natural
Habitats. PLoS ONE, 3(10), e3432. https://doi.org/10.1371/journal.pone.0003432
Tetreau, G., Alessi, M., Veyrenc, S., Périgon, S., David, J.-P., Reynaud, S., & Després, L.
(2012). Fate of Bacillus thuringiensis subsp. israelensis in the Field: Evidence for Spore
Recycling and Differential Persistence of Toxins in Leaf Litter. Applied and Environmental
Microbiology, 78(23), 8362–8367. https://doi.org/10.1128/aem.02088-12
Tetreau, G., Bayyareddy, K., Jones, C. M., Stalinski, R., Riaz, M. A., Paris, M., … Després, L.
(2012). Larval midgut modifications associated with Bti resistance in the yellow fever mosquito
using proteomic and transcriptomic approaches. BMC Genomics, 13(1), 248.
https://doi.org/10.1186/1471-2164-13-248
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Control of Zika Vectors. Frequently Asked Questions. 2018.
https://www.valentbiosciences.com/publichealth/wp-content/uploads/sites/4/2017/02/faq-
vectobac-wdg-applications-for-zika-virus-vectors.pdf
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Background document for development of WHO Guidelines for Drinking-water Quality. 2009.
http://www.who.int/water_sanitation_health/gdwqrevision/RevisedFourthEditionBacillusthuringi
ensis_Bti_July272009_2.pdf
25
Conditions that Escalate Risk of West Nile Virus to People
Actions to Reduce Risk of West Nile Virus to People
No infected moquito
samples
Mosquito sample
positive for WNv
Vector Index greater
than 0.5 by mid-July
Multiple positive
samples during same
week
Consecutive weeks
of positive samples
Vector Index exceeds
0.75
Vector Index exceeds
0.75 in multiple
samples and
escalates over time
Human cases above
average
City reminds the
public to avoid
bites and drain
standing water
City press release
when first positive
mosquito pool
occurs and when
first human case
occurs in the city
City increases
signage at
trailsheads and
Parks and
Recrecation
facilites
City provides
mosquito repellent
at recreational
facilities
City increaes
NextDoor and
social meda posts,
newsstories, etc. to
remind public of
increasing risk
Trainings to city
staff to recognize
and decrease
breedings sites
Consider "yard
audits" to reduce
breeding sites in
urban areas
Neighborhood
leaders assist
neighbors with yard
audits and provide
city information to
avoid bites
Consider additional
testing to pinpoint
hotspots
Map human cases,
if occur in clusters,
focus on working
with
neighborhoods to
reduce risk
26
2018 Environmental Advisory Board Calendar
January 3 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Scoping and Planning for 2018 Joint Council/EAB SS Brett KenCairn
New Member Recruitment Board
Materials due by noon on Wed, Dec 27, emailed to EAB by 4 pm.
February 7 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
RECs Yael Gichon/Kimberlee Rankin
Preparing for the Joint Council/EAB Study Session
Materials due by noon on Wed, Jan 31, emailed to EAB by 4 pm.
March 7 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Updates to the Integrated Pest Management Policy and
Associated Programs
Rella Abernathy (60 mins)
Urban Forest Management Strategy Kathleen Alexander (30 mins)
Preparing for the Joint Council/EAB Study Session Board
Goodbye and Thank You to Brad All
Materials due by noon on Wed, Feb 28, emailed to EAB by 4 pm.
April 4 - Retreat
May 16 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff/Board Member
6400 Arapahoe Kara Mertz
Debrief Retreat Brett KenCairn
Preparing for a Joint Advisory Board Meeting on
Ecosystem Related Issues
Update on the Joint Council/EAB Study Session Brett KenCairn
Materials due by noon on Wed, April 25, emailed to EAB by 4 pm.
June 6 Meeting
Public Hearings Staff
27
Discussion Items/Updates/Matters for the Board Staff
GAC Memo
Joint Board Meeting Prep Board
Joint Council/EAB Study Session Prep Board
Materials due by noon on Wed, May 30, emailed to EAB by 4 pm.
July 18 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Joint Board Meeting Planning Board
Materials due by noon on Tues, July 11, emailed to EAB by 4 pm.
August 1 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Prairie Dog Working Group Phase 2 Report and Staff
Analysis
Valerie Matheson – 30 mins
Revenue Needs and Potential Funding Sources for
Climate Commitment Work
Kendra Tupper and Kimberlee
Rankin – 60 mins
Joint Board Meeting Planning Board
Materials due by noon on Wed, July 25, emailed to EAB by 4 pm.
August 29 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Alpine-Balsam Area Plan Joint Board Meeting Board
Welcome Justin Brant to the Board Board
Joint Board Meeting Planning Board
Materials due by noon on Wed, Aug 22, emailed to EAB by 4 pm.
October 3 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Muni Update Steve Catanach
Options to Update and Improve Boulder’s Mosquito
Management Program
Rella Abernathy
Joint Meeting Debrief Board
Annual Letter to City Council Board
Materials due by noon on Wed, Sept 26, emailed to EAB by 4 pm.
28
November 7 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Joint Council/EAB Study Session Prep Board
Annual Letter to City Council Board
Materials due by noon on Wed, Oct 24, emailed to EAB by 4 pm.
December 5 Meeting
Public Hearings Staff
Discussion Items/Updates/Matters for the Board Staff
Joint Council/EAB Study Session Prep Board
Annual Letter to City Council Board
Materials due by noon on Wed, Nov 28, emailed to EAB by 4 pm.
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