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Avian habitat management and trail development

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Title:
Avian habitat management and trail development case study of Two Ponds Wetland Preserve
Creator:
Griffis, Jennifer L
Publication Date:
Language:
English
Physical Description:
vii, 61 leaves : illustrations, maps ; 28 cm

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Subjects / Keywords:
Bird refuges -- Planning -- Colorado -- Arvada ( lcsh )
Bird refuges -- Planning ( fast )
Colorado -- Arvada ( fast )
Genre:
bibliography ( marcgt )
theses ( marcgt )
non-fiction ( marcgt )

Notes

Bibliography:
Includes bibliographical references.
General Note:
Submitted in partial fulfillment of the requirements for thesis research and programming, Master of Urban and Regional Planning, Urban and Regional Planning Department
Statement of Responsibility:
by Jennifer L. Griffis.

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Source Institution:
University of Colorado Denver
Holding Location:
Auraria Library
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
28445746 ( OCLC )
ocm28445746
Classification:
LD1190.A78 1993m .G758 ( lcc )

Full Text
AVIAN HABITAT MANAGEMENT AND TRAIL DEVELOPMENT:
i
CASE STUDY OF TWO PONDS WETLAND PRESERVE
by
Jennifer L. Griffis
B.S.. Bloomsburg University of Pennsylvania, 1989
A thesis submitted to the
Graduate School of Architecture and Planning
University of Colorado at Denver
in partial fulfillment
of the requirements for the degree of
Master of Urban and Regional Planning
Enviromental Planning Emphasis
1993
I


i
t
This thesis for the Master of Urban and Regional Planning
degree by
Jennifer L. Griffis
has been approved for the
Graduate School of Architecture and Planning
Environmental Planning Emphasis
by
a? /?, m
(/Date1


Griffis, Jennifer L. (Master of Urban and Regional Planning, Environmental Planning Emphasis)
Avian Habitat Management and Trail Development: Case Study of Two Ponds Wetland
Preserve
Thesis directed by Associate Professor Peter V. Schaeffer, Ph.D.
ABSTRACT
This thesis suggests methods for the management of a natural areas, and development
of interpretive programs for a specific site. It describes ways to both enhance avian habitat and
increase viewing of birds through management and interpretive programs.
Several case studies were examined which researched trail and park management with
respect to human activity, as well as avian species. A literature review was done to examine
factors influencing habitat selection for birds, and management and development of nature
preserves. The information gathered was then used to analyze the Two Ponds Wetland
Preserve, an 80 acre open space located in Arvada, Colorado. The U.S. Fish and Wildlife
Service is in the process of developing a management plan and environmental education
program for the Two Ponds Wetland Preserve.
The following conclusions were made after analyzing the Two Ponds site. There are
abundant resources to support a substantial avian population. The unique features such as open
water and old growth trees make it an extremely worthwhile area to protect. The management
plan should be flexible, include the community, and consider both the visitor's satisfaction and the
protection of the environment. Due to the relatively small size of the site, interpretive program and
frail placement in particular must be carefully considered in order to provide the greatest variety of
hi
experiences for the visitor.


Included in the thesis is a suggested trail layout for the Two Ponds site. The suggested
layout passes through a wide variety of habitats, and incorporates several features such as trail
direction and specific placement of bird blinds in an effort to aid bird viewing.
The urban location of the Two Ponds Wetland Preserve makes it a valuable resource for
the surrounding metropolitan area. With proper management, the Two Ponds site will continue to
support a variety of wildlife, and provide and opportunity for urban dwellers to experience and
learn about the environment.
This abstract accurately represents the content of the candidate's thesis. I recommend its
publication.
Signed
Peter V. Schaeffer, Ph.D.
IV


Dedicated to Quint.
Thanks for all of your support and encouragement.
We made it!!


CONTENTS
Chapter 1: Introduction.................................................................1
Chapter 2: Background Information.......................................................5
Review of Selected Studies.....................................................5
Study 1: The Nymph to Emerald Lake Trail Corridor in Rocky Mountain
National Park...........................................................6
Study 2: The Common Loon in Boundary Water Canoe Areas of
Northeastern Minneapolis...............................................11
Factors Influencing Habitat Selection for Birds................................16
Habitat Resources......................................................16
Habitat Structure......................................................18
Management and Development of Nature Preserves.................................21
Resource Management Plan Development...................................21
Trail Development......................................................26
Concepts of Interpretive Programs......................................29
Chapter 3: Study Site: The Two Ponds Wetland Preserve..................................31
Location of Site...............................................................31
Current Land Use and Ownership of the Site.....................................31
Proposed Land Use of Site......................................................36
Chapter 4: Analysis of Two Ponds Wetland Preserve......................................39
Habitat Resources of Site......................................................39
Habitat Structure of Site......................................................43
Suggestions for Management of the Site.........................................49
Suggestions for Trail Design and Placement on the Site.........................53
Chapter 5: Conclusions.................................................................58
Reference List.........................................................................60
VI


FIGURES
Figure 1: Location Map for Nymph to Emerald Lake Trail Corridor and Study Area.............7
Figure 2: Location Map for Boundary Waters Canoe Area.....................................12
Figure 3: Diagram of Management Process...................................................24
Figure 4: Vicinity Map for Two Ponds Wetland Preserve.....................................32
Figure 5: Existing Land Use and Vegetation................................................33
Figure 6: Existing Landownership..........................................................35
Figure 7: Site Management Plan Alternative No. 2........................................38
Figure 8: Aerial View of Two Ponds Wetland Preserve.......................................44
Figure 9: Habitat Structure of Two Ponds Wetland Preserve.................................45
Figure 10: Grouping of Avian Species by Habitat Type......................................47
Figure 11: Suggested Trail Placement for Two Ponds Wetland Preserve.......................55
vii


CHAPTER 1
INTRODUCTION
As the population becomes more environmentally conscious, there seems to be a trend
towards greater use of our natural areas as people try to "get back to nature". Unfortunately, an
increase in the number of users also increases the impacts that humans have on the environment.
To control these impacts, it is necessary to carefully plan and regulate wilderness areas. We
need to recognize that without some type of orderly method of wilderness use, natural areas
experiencing high use will undoubtedly be destroyed. Planning is an especially important aspect
of wilderness protection when the wilderness is located within an urban area.
Designated natural areas are highly valuable amenities in urban settings. In many
instances, these designated open spaces are the only contact urban dwellers have with nature.
People need to touch, smell and hear nature to truly appreciate the environment around them.
These sensory elements can not be experienced through a text book. Natural open spaces
within urban areas provide an ideal opportunity for youngsters and adults to be exposed to nature.
The following illustrates how lifestyles have changed over the years due to the onset of
urbanization. In 1913 the U.S. Fish and Wildlife Service (USFWS) produced a publication titled
"Fifty Common Birds of Farm and Orchard". By 1974 there were far fewer farms and orchards and
the USFWS revised the publication calling it "Fifty Birds of Town and City", with the subtitle "Non-
birdwatchers Handbook". The current edition of the publication emphasizes changes which have
occurred in avian habitat due to development of cities and suburbs. This edition is geared
towards the city dweller who knows little or nothing about birds. (Wallin 1976, 331) In essence,
there must be a re-education of the general public about the environment around them. Creating
a more environmentally knowledgeable public will hopefully create a better sense of stewardship


for the environment. This in turn wiil aid in protecting nature as the conflict continues between
development and preservation of land.
The USFWS is currently involved in trying to preserve a wildlife area which is located in
Arvada, Colorado and known as the Two Ponds Wetland Preserve. The USFWS is seeking
acquisition of the entire 80 acre site in order to manage the area as an urban wildlife refuge. In
addition to managing the area as a wildlife refuge, the USFWS intends to develop self-
interpretive trails on the site so that it may be used for environmental education purposes.
Because of the site's urban location, it serves as a prime opportunity to start the process of
exposing urban dwellers to nature.
The USFWS has already conducted an Environmental Assessment which resulted in a
finding of no significant impact on the human environment from the proposed action (USFWS
1992. ii). However, the proposed trail system along with increased pedestrian traffic on the site
will inevitably have an impact on the wildlife and the natural habitat of the site. It is possible to
minimize the negative impacts on the site due to increased use by developing an understanding
of the habitat of the site and the needs of the wildlife found on the site. Once these issues are
identified, a management plan which addresses potential problems can be developed and used
as a means by which to control use on the site.
Therefore, this paper examines the question, what is the best way to manage and
develop the Two Ponds Wetlands Preserve? This question is then taken a step further by looking
specifically at avian habitat, and determining management techniques and trial design which will
enhance avian habitat and enhance the opportunity for visitors to view birds.
According to the environmental assessment produced by the USFWS on the Two Ponds
Wetland Preserve, there are numerous mammals, reptiles, amphibians and birds supported by
the 80 acre site. Birds are a most enjoyable part of nature. Approximately 25% of the United
States population engages in some form of bird watching (Faaborg 1988. 394). The degree of
2


involvement in bird watching ranges from observing a backyard feeder to traveling abroad to view
new species in order to expand a life long checklist. The amount of money spent on birding
paraphernalia is indicative of the popularity of bird watching. For example, on an annual basis in
the United States over $500 million dollars is spent on bird seed. $100 million on bird feeders,
bird boxes and bird baths, and another $18 million dollars on field guides and other books related
to birds (Faaborg 1988, 394). With such a large public interest in the avian species, it is a logical
step to protect and preserve the birds located on a particular site and their habitat. In order to
protect avian habitat, it is necessary to understand what kind of habitat and resources are needed
to support a healthy avian population. Chapter 2 wiil address this topic in detail.
Once the basics of avian habitat are understood, this information may then be used when
creating a management plan for an area. Too often a generic management plan is simply
imposed on an area instead of a plan tailored to meet the needs of the specific site. When
generic plans are used, the end result is usually an ineffective management plan which
mismanages an area in such a way that more damage to the environment occurs than if there
were no plan implemented. To illustrate, consider the results if a management plan designed for
Yellowstone National Park was duplicated and applied to the Great Sand Dunes National Park.
The Yellowstone plan would include extensive regulations concerning the conduct of visitors in
the areas containing active geysers. Such regulations would be useless if applied to the Great
Sand Dunes National Park. In addition, regulations needed to direct the conduct of those visiting
the Dunes would be missing from the plan, resulting in a greater potential for destructive activity
by visitors. It is easy to see why management plans are site specific and need to be created
individually for each area. That is not to say, however, that basic concepts from a variety of
management plans should not be examined before creating a site specific plan. Surveying a
number of different management plans allows for the adoption of management strategies which
have proven to be successful in the past, and the removal of strategies which have failed in the
3


past. Much has been written about the techniques which should be used to create effective
management plans. These points will also be discussed in detail in Chapter 2.
Aside from managing the site, the USFWS plans to develop a trail system which will
serve primarily as an environmental education facility (USFWS 1992. 2). Because the Two Ponds
Wetland Preserve is a relatively small site, it is particularly imperative that the placement of the
trails be carefully considered. On such a small site, the trails have the potential to significantly
impact the habitat and wildlife existing on the site. The USFWS plans to develop two loop trails
located in the northeast corner of the site in an area of approximately 22 acres (USFWS 1992,14).
Because the trails will be used primarily for interpretive programs, they will need to incorporate
as many different types of habitat and natural features as possible in order to maximize the
learning experience. This fact adds to the importance of trail placement. General trail design and
basics for the development of interpretive programs will be discussed. As with the management
plan, suggestions for trails and interpretive programs which enhance bird viewing will be
examined.
As a final product, this paper is intended as an aid to the USFWS as they work to create a
management plan and interpretive trail program for the Two Ponds Wetland Preserve. The
research presented on management plans and interpretive trail programs should be useful when
developing the general guidelines of the Two Ponds management plan. As the USFWS
identifies specific categories of interest on the site, hopefully the research presented on avian
habitat will encourage development which takes into consideration the importance and the needs
of the birds inhabiting the site.
4


CHAPTER 2
BACKGROUND INFORMATION
The Background Information sections discuss the literature which was reviewed to build
the information base needed to conduct the analysis of the Two Ponds Wetland Preserve. The
main goal of this paper is to examine management plans and interpretive trail design, and then to
relate these functions to avian habitat. During the research process, it was found that there is a
lack of information which combines the issues management and trail design as they relate to
avian habitat. The two studies which follow each illustrate one half of the whole equation. The
information gathered from these studies has been synthesized and used in the analysis of the
Two Ponds site.
Review of Selected Studies
Numerous studies have been done which research the effects of recreation on natural
areas. Two examples have been selected to be examined due to their combined relevance to
the objectives of this paper. The first study concentrates on environmental damage occurring on
a trail corridor in Rocky Mountain National Park. This study will aid in the examination of
management plans and trail design. The second study involves research of a specific bird
community. Common Loons ( Gavia immer), and how they react to encroachment by recreational
users. This study presents information on how birds react and how avian habitat is effected by
recreational use of an area. Together, these two studies present valuable information which may
be applied to the Two Ponds site.
5


Study 1: The Nv.mph to Emerald Lake Trail Corridor in Rockv Mountain National Park
This study was done by Mark L. Huddleston on the impact of increased recreational use on
the Nymph Lake to Emerald Lake trail corridor located in Rocky Mountain National Park (see
Figure 1). Historically, this is the most heavily used segment of trail within the park (Huddleston
1980,16). The scope of the study was to identify where ecological degradation had occurred
within the selected study area, to assess the degree to which the degradation had occurred, and
to present possible reasons why degradation had or was taking place (Huddleston 1980, ii).
Given the scope of the study, the two main purposes of the study were as follows.
1. To establish a method by which to monitor impacts on the trail
2. To formulate recommendations as to how specific impacts on particular segments of
the corridor may be reduced or eliminated
(Huddleston 1980. 5)
It is important in any study to first measure the existing conditions of the study area. This
allows for a comparison to be made between the initial and the final state of an area during the
study period. In Huddleston's study, the nature and extent of ecological impacts which occurred
due to heavy recreational use were determined by mapping all existing, measurable ecological
degradation along the Nymph Lake to Emerald Lake trail corridor. Several observation points
were identified along the trail corridor. These were the points from which data was recorded.
The observation points were chosen because they were thought to be good examples of areas
which were being subjected to heavy use. The amount of ecological degradation occurring at
each site was determined by using what Huddleston called a Scale of Visitor Impact. The scale
consisted of a range in degree of impact from very light, a rating of zero, to very heavy, a rating of
five. (Huddleston 1980, ii)
The second part of the study tried to determine why the ecological impacts were
occurring. Data to answer this question was gathered by observing visitor's use patterns as
6


Figure 1: Location Map for Nymph Lake to Emeraid Lake Trail Corridor
and Study Area
(Source: "Day Use Impac* Study of the Nymph to Emerald Lake Trail Corridor", Huddleston, 1980.)


they related to specific site and trial characteristics. For example, it was important to observe how
hikers would react to a natural obstacle such as a snow patch or fallen tree. Would they travel
around the obstacle and then return to the designated path, or continue to break their own trail
away from the path?
Several specific problems were identified by Huddleston. Braided and parallel trails
were found quite frequently. Such trails occurred most commonly where there was an obstruction
in the designated trail. For instance, a stretch of snow covered or muddy trail would cause the
hiker to leave the designated trail and forge a new route parallel to the original trail in order to
avoid the obstruction. In most cases, the hiker would return to the designated trail after passing
the obstruction. A second problem occurred when the hikers would not return to the designated
trail. This resulted in the creation of new trails continuing throughout the area surrounding the
designated Nymph Lake to Emerald Lake trail corridor. Eventually the random trails became so
worn that it was difficult to distinguish between the planned trails and the accidental trails. A third
problem involved the widening of trails in areas where hikers would gather to observe the
scenery. The widening of the trail resulted in root exposure for the trees adjacent to the trail.
Trail widening also exposed a greater amount of soil which was then subject to erosion. The
final problem discussed by Huddleston was the shortcutting which was found in areas where the
trail had a large number of switchbacks. Shortcutting was another factor contributing to the
problem of erosion. (Huddleston 1980,16)
Huddleston concluded that the most important aspect involved in protecting the habitat
and ecological stability of a recreational area is to have a good management plan to govern the
use of the area (Huddleston 1980,13). In order to create an adequate management plan, there
must first be an understanding of the carrying capacity of a site. Huddleston presents the concept
8


of carrying capacity by noting the definition given by researchers Lime and Stankey:
'The character of use that can be supported over a specified time by an area developed
at a certain level without causing excessive damage to either the physical environment or
the experience for the visitor."
(Huddleston 1980.1)
This definition of carrying capacity is favorable because it considers both the environment and the
user of the environment. A good management plan is one that finds a balance between
appropriate protection and sufficient use of a natural area. Lime and Stankey also give four basic
components to be used in determining the carrying capacity of an area:
- management objectives of the area
- visitor attitudes, experiences and expectations
- recreational impacts on physical resources
- nature of biological resources and nature of the ecosystem
(Huddleston 1980, 2)
Carrying capacity is a difficult value to determine because it is dependent on the unique features
and particular uses of each individual site. For example, if a site with a dense ground cover and
one with very little ground cover are both subjected to intense pedestrian use, the site with more
ground cover will be less prone to erosion due to the stabilizing effects of the vegetative cover.
Hence, the first site has a higher carrying capacity than the site with a sparse ground cover
because it is able to tolerate more intense use before experiencing the negative effects of
erosion. This is just one simplified example of why it is necessary to determine an individual
carrying capacity for each site based on the specific features of that site.
Other key points that may be learned from Huddleston's study involve the development of
management objectives and means by which to accomplish management goals. For Rocky
Mountain National Park, the primary management goal for the Nymph to Emerald Lake trail
corridor was to preserve the ecology of the area as well as restore any damaged areas to their
9


natural state (Huddleston 1980,15). In order to accomplish these goals Huddleston made two
suggestions:
1. regulate use by the design parameters of the trail
2. regulate types and levels of use through directives in the management plan
(Huddleston 1980,15)
Huddleston found that in general, the ecological damage which was occurring within the study
area was due to design flaws in the trails. The hikers were not being guided along routes which
were located or maintained in a way to protect resources. Additionally, the trails were not taking
the hikers where they wanted to go. The hikers had to divert form the trail to reach obvious points
of interest. Following this thought, Huddleston stated that many times physical impacts on natural
resources are not directly related to the level of visitor use. The more important considerations
with respect to physical impact are use patterns, specific activities, and the natural processes
operating within the ecosystem itself. Therefore, if trails are designed and maintained properly,
and if abusive use is curtailed through good management plans, a large number of people will be
able to use and enjoy the trails without causing significant physical damage to the environment.
(Huddleston 1980, 21)
The key points which were made in the Nymph to Emerald Lake Trail study which will be
useful when considering the Two Ponds Wetlands Preserve site are as follows:
- It is important to take an initial inventory of a site, noting the original condition of the
habitat and existing species found on the site. This inventory then becomes the
base data used to determine the degree of change occurring on the site over
time.
- Trail design should be used to control where and how people use the site.
- A carrying capacity should be determined for the site based on management
objectives, the natural resources of the site, and consideration of the users
needs.
10


Study 2: The Common Loon in Boundary Waters Canoe Areas of Northeastern Minneapolis
This study involved researching the effects of recreation on the common ioon population
in the Boundary Waters Canoe Area (BWCA) which is located in the Superior National Forest in
Northeast Minnesota (see Figure 2). The BWCA is the second largest and most heavily used
area in the Minnesota wilderness system (Titus and VanDruff 1981,9). The specific site for the
study was the Knife Lake area which is located on the northern boundary of the BWCA.
For the study. 36 lakes were surveyed which ranged in size from 9.7 to 655 hectares
(23.9 to 1,618.5 acres). The only exception was Knife Lake which covers 2.241 hectares (5,537.5
acres). Outboard motors were only permitted on 5 of the 36 lakes. Islands suitable for loon
nesting were found on 28 (75%) of the 36 lakes. (Titus and VanDruff 1981, 12)
The study was conducted from mid-May to mid-August for a two year period. 1975-1976.
The loon population during that period was found to be151 adult birds, a density of approximately
1 adult loon per 35 hectares (86.5 acres) of water. Observation of the birds was done by using
two-man teams traveling in canoes. In addition to taking a census of the loon population, the goal
of the research was to observe how recreation activity affected the loon's nesting and brood
rearing success. Much of the time was spent observing the recreational activity in the area and
noting the proximity of the activity to nest sites and the loon's response to the activity. (Titus and
VanDruff 1981.15)
Researchers Titus and VanDruff outlined three main questions which they wanted to
address through the study:
- How will the loons be affected by increased impact on habitat by visitors?
- Will loons be able to tolerate moderate to heavy recreational disturbances provided
direct malicious actions by humans are modified?
- Which recreational patterns are most destructive?
(Titus and VanDruff 1981,8)
11


CANADA
Map of Minnesota showing the Boundarv Waters Canoe Area within the Superior National Forest.
Figure 2: Location Map for Boundary Waters Canoe Area
(Source: "WicSte Monograph*: Response ot the Common Loon to Recreational Pressure in tie Boundary Waters Canoe Area.
Northeastern. Minnesota*. Titus and VanDiul. 1981.)


By asking these questions. Titus and VanDruff were ultimately trying to develop recommendations
for a management plan for the BWCA. An effective plan in this case wouid insure the
maintenance of a substantial number of breeding pairs with satisfactory nesting success in the
loon population of the BWCA. (Titus and VanDruff 1981,8)
The results of the study were very useful in answering the questions presented by Titus
and VanDruff. The primary impact from the increased use of the area was that the loons were
more likely to be flushed from their nests. An increase in flushing had specific negative effects on
the loons. Titus and VanDruff found that any time the adult loon was absent from the nest, the
eggs were in much greater danger. For instance, there was an increased chance of predation of
the eggs by small mammals. Not only was the nest an easy target for predators when the adult
was absent, but the commotion caused by flushing brought attention to the nest site making it
easier for the predator to find the nest. (Titus and VanDruff 1981,40)
Another problem with prolonged absence from the nest was the cooling of the eggs. If
the adult loon stayed away from the nest for an extended period, the eggs would cool to a point
which would make them unviable for hatching. In addition, in several cases Titus and VanDruff
reported that the abrupt flushing of the adult from the nest caused eggs to be knocked into the
water where they could not be recovered by the adult loon. (Titus and VanDruff 1981.39)
Titus and VanDruff found that disturbance by humans early in the season often caused
the loons to delay nest building in an effort to avoid conflict with humans. Unfortunately, the
longer the loons waited to build their nests the more intense the recreational activity became.
Eventually the loons had to tolerate human disturbance and build their nests if they were to raise a
brood before the lakes became frozen for the winter. (Titus and VanDruff 1981.45)
An interesting discovery was made with respect to the loons ability to tolerate human
disturbance. The researchers found that when loon activity on extremely isolated lakes was
compared with the loon activity on heavily used lakes, the loons in the isolated areas showed a
13


greater amount of anxiety upon the approach of humans. The birds would put on aggressive
displays and use a great deal of vocalization when approached. Conversely, the loons on the
lakes receiving high use would rarely vocalize when approached and had a much lower flushing
distance than birds on the isolated areas. These observations indicate that the birds in the high
use areas were becoming desensitized to humans. This implies that it may be possible for the
loons and humans to coexist on the lakes without any adverse affects on either party. (Titus and
VanDruff 1981,44)
However, this peaceful coexistence between the loons and humans depends solely on
the visitor's ability to respect the loons' habitat and not become too invasive on the loons territory.
Titus and VanDruff reported that several loon chicks were killed due to handling by hikers and
boaters (Titus and VanDruff 1981,39). These people did not intentionally kill the chicks, but they
were uneducated as to the consequences of their actions. This is a prime example of why
people must be educated about nature in order to respect and preserve it. More education
generally results in a greater respect for nature, and a greater effort to preserve nature.
The most destructive recreational use was determined to be boats with motors. Titus
and VanDruff observed that motorized boats invariable caused greater disturbance to the loons
than non-motorized boats (Titus and VanDruff 1981,40). Loons which were located on lakes
where motors were prohibited were able to establish nests and incuDate eggs without any major
disturbances. This was an advantage over loons nesting on lakes where motors were allowed,
and resulted in a more successful rate of hatching and brood rearing than on the lakes where
motors were prohibited (Titus and VanDruff 1981.51).
Titus and VanDruff proposed several management recommendations for the managers
of the Superior National Forest. The first suggestion was to develop a conservation ethic among
the public, giving visitors an understanding of nature which would allow them to live with sensitive
species such as the loon without causing its decline. This could be accomplished through short
14


educational programs to be presented to users of recreational areas before they are permitted to
enter sensitive areas. Secondly, Titus and VanDruff suggested that managers must decide how
to limit visitor use in order to accommodate the breeding loon population. They questioned
whether it would be more helpful to the loon population to concentrate use in certain areas, or
would it be better to have dispersed use throughout the entire area. A third suggestion was to
discourage or even disallow use of small islands by campers and boaters. The majority of loon
nests were located on islands because of the islands natural protection from predators.
Therefore, use of the islands tends to affect a large percentage of nesting loons. A fourth
suggestion made by Titus and VanDruff was to consider known nest sites when creating new
campsites. The new campsites should be placed away tram known nest sites, and existing
campsites which are close to known loon nest sites should be closed. Finally. Titus and VanDruff
firmly opposed the posting of existing nest sites to warn visitors not to enter the area.
Unfortunately, this tactic usually draws more attention to the nest and creates a greater
disturbance to the area than if the nest was left alone with its natural cover. Titus and VanDruff
noted that most nests which were disturbed in the BWCA were accidently discovered, the
remainder of the nests go undetected by recreational users. (Titus and VanDruff 1981,54)
The key points which were made in this study which will be useful when considering the
Two Ponds Wetlands Preserve site are as follows:
- It is extremely important to educate the public about the environment and the intricate
systems found in nature. Hopefully the effort to educate people will cause a
greater respect for nature, and in turn reduce the amount of damage inflicted on
the environment by humans.
- A management plan should be used to limit the number of users and types of use. The
plan should allow only uses which are compatible with the habitat and species of
the site.
- Particularly sensitive areas on the site should be identified and use should be
restricted or prohibited in these areas.
- Although animals may adapt to the presence of humans, there must be restrictions to
keep humans from encroaching too extensively on the animal's habitat.
15


Factors Influencing Habitat Selection for Birds
In an effort to suggest management techniques and trail design for the Two Ponds
Wetland Preserve with respect to avian habitat, it is necessary to understand those factors which
influence habitat selection in birds. The fact that the Two Ponds Preserve is located within an
urban setting raises some interesting questions with respect to the habitat on the site.
- How is the habitat affected by the surrounding human activity?
- Can the site be effectively managed to control the encroachment of urbanization?
- What is the critical point at which the habitat and resources of the site are no longer
suitable to support a variety of bird species?
In order to answer these and other questions, it is necessary to consider how habitat resources
affect birds. Given this information it will be possible to optimize the habitat in the Two Ponds
area so as to attract and sustain a variety of avian species.
Habitat Resources
The resources of an area are those elements which allow for a particular species to
successfully exist in that area. A resource is an item which must be used by an organism but not
necessarily consumed, and it must be potentially limiting but not necessarily always limiting
(Wiens vol. 1 1989, 323). Food is an obvious resource to be considered, but items such as nest
sites, perch sites, and adequate cover are also important resources.
Once the resources of a site have been defined, the resources must be analyzed with
respect to their abundance, availability and use (Wiens vol. 1 1989, 323). Abundance of a
resource may vary over time and space. For instance, insects are more abundant in the spring
and summer than in the fall and winter. If a particular species is dependent on insects as a food
sources, that species will need to migrate throughout the year to areas where insects are
available.
16


In general, the availability of a resource is of greater importance than the abundance of
that resource (Wiens vol. 1 1989, 323). For exampie. widely scattered seeds are less available to
a species than if the seeds are clumped together in patches. A bird foraging for seeds would
need to spend an exorbitant amount of energy to consume a sufficient amount of food if the seeds
were widely scattered. However, if the seeds were clumped in patches the bird would expend
less energy foraging, and therefore gain greater benefit from the resource.
How a resource is used is influenced by the morphology, physiology and behavior of a
species (Wiens vol. 1 1989, 324). For example, a pond is a habitat resource for many different
species of waterfowl. The reason that several different species can share a pond is due to the
different ways in which species use the resource. Mallards [Anas p/atyrhynchos) are dabbling
ducks. These ducks feed on the edges of a pond where they can dip the upper half of their body
into the water, tipping the bottom half of their body upward, and glean food from the plant life
found in shallow water. The Western Grebe (Aechmophorus ocadentatis) on the other hand is a
diving bird. These birds will feed in the deeper waters, diving to feed on the bottom of the pond.
The Belted Kingfisher [Megaceryte a/cyori) uses yet another feeding technique. These birds
perch in trees along the ponds edge and dive into the water catching small fish. Hence, these
various species can coexist in the same habitat because they each use the resources of the pond
very differently.
To reiterate a previous point, there are a number of very important resources needed to
sustain a healthy population other than food. For instance, nesting sites can become a limiting
factor for a species, particularly if the species are cavity nesters which use existing holes in trees
as nest sites. On any given site, there are only a limited number of suitable trees with cavities
available for nesting. These are usually the older trees in a stand: therefore, younger stands of
trees are generally not able to support cavity nesting species.
17


Another non-consumable resource is perch sites. Many larger birds such as hawks
frequently use perch sites to scan the surrounding fields. The perches used by hawks are
different than those required for small song birds. Therefore, a variety of perches are needed on
a site to support a wide range of species.
In summary, the resources of a site play a critical role in the type of birds which can be
expected to reside on a site. When creating a management plan, it is important to analyze the
resources available, and then determine howto protect these specific resources. In addition to
the protection of existing resources, it may be possible to enhance the resource base by
introducing appropriate vegetation or by creating more nest sites through the construction of nest
boxes. In any event, the goals of the management plan which address the type of species
desired on the site must be considered before resource alterations are made.
Habitat Structure
The habitat structure of an area refers to the way in which the resources are
geographically situated as well as the type of resources found on a site. If one pictures looking at
the earth from an airplane, it is evident that specific patterns are formed by the presence or lack of
vegetation and water. These patterns form the habitat structure of a site. It is important to
understand the influences of habitat structure because the structural aspects of habitats are
directly related to the type and number of bird species found in that habitat. Research of habitat
structures show that the more structurally diverse a habitat is. the greater the number of species
found in that habitat (Cody 1985, 32). By analyzing vegetation and water patterns it is possible to
determine which species are likely to be found in a particular area.
Another factor which comes into play with respect to habitat structure is the size of distinct
habitats. This is commonly referred to as the patch size. Patch size is most frequently used to
describe the size of wood lots or forested areas. Researchers have found that many species of
18


birds have minimum patch size requirements for their habitats. For example, in a study which
looked at shelter belts (patches of trees planted as windbreaks in open grasslands), the
American Robin ( Tundus migratorius) was found in large numbers in shelter belts one-fifth of the
size needed to support Black-billed Cuckoos ( Coccyzus erythropthaJmus) (Cody 1985, 38).
Therefore, regardless of the qualily of the habitat, the cuckoo would not be able to exist in the
shelter belt unless it was large enough to meet its spatial needs.
Many factors contribute to the creation of habitat patches. Cutting of significant numbers
of trees will alter the size and shape of a forest. Urbanization is a major factor in habitat
segmentation as more and more developments are built on open tracts of land. Most
developments, either voluntarily or due to imposed guidelines, provide for tracts of land to be
designated as open space. It is questionable whether patches of natural areas left as open space
in subdivisions are capable of supporting wildlife. These urban patches may be too small and
too far removed from larger patches of natural habitat to attract and sustain wildlife.
Faaborg points out that the same dynamics seen on actual islands surrounded by water
are found on patches of habitat which are surrounded by unsuitable habitat. When considering
water isolated islands, there is a factor called Island Biogeographic Theory (Faaborg 1988, 431).
This theory states that birds found on smaller islands are most likely to be species which are
good colonizers and adapt well to different environments (Faaborg 1988, 431). Conversely, those
species found on large islands are usually poor colonizers with very specific habitat requirements
(Faaborg 1988, 431). Relating this theory to land surrounded, habitat islands implies that small
patches of habitat will attract those species which are good colonizers and do not have very
specific habitat requirements. Species such as House Sparrows (Passerdomest/cus), European
Starlings (Stumus vu/garis) and House Finches ( Carpodacus mexicanus') would fall under the
category of non-habitat specific colonizers. Unfortunately, these species are often considered to
be pest species, and limit the amount of habitat available for more desirable and unique species.
19


The creation of many small patches of habitat through the division of land for
development purposes is generally seen as a negative activity. However, Faaborg notes that
those species which thrive in habitats found on the edge between forest and fields are doing well
in recent times because this is the type of habitat which is produced by human activities (Faaborg
1988, 429). Cody discusses how ecotones. the areas between habitat types, seem to be areas of
higher productivity (Cody 1985, 35). Therefore, the creation of these ecotones between forest
and field may actually be beneficial to some bird species. The negative side of this argument is
that those species which need interior forest habitat are greatly affected by the fragmentation of
forest habitat (Faaborg 1988, 431).
Given the basics of habitat resources and structure, the next step is to examine some of
the theories of habitat selection in birds. Cody suggests that habitat selection may be broken
down into two possible explanations, free choice and return to natal habitat (Cody 1985, 29).
Many studies have been done to track why birds return to particular habitats. In 1949, a
researcher named Svardson studied Wood Warblers and found that young male warblers were
influenced in habitat and territory choice by the older male warblers. The older warblers returned
from wintering grounds earlier than the young warblers (Cody 1985, 29). As a result, the older
birds had first choice in habitat selection, and the younger birds had to select from the remaining
habitat. The older warblers most likely used free choice in habitat selection, but the younger
warblers were influenced by the older warblers' choice in habitat.
The role of natal habitat and previous nesting experience in habitat selection was studied
by Herlugson in 1981 (Cody 1985, 29). He found that in Mountain Bluebirds (S/a/ia curruco/des),
first time breeders would tend to choose their natal type of nest box for nest construction. He also
found that females would chose the same territory and type of nest box year after year if
successful breeding occurred. However, if unsuccessful breeding occurred, the female would
switch territory and type of nest box (Cody 1985, 29). From this study it may be implied that
20


habitat stability and suitability will greatly influence the return of a bird to previously used habitat.
Taking this logic a step further, one can see the importance of managing a resource area in sucn
a way to prevent critical changes to avian habitat in an effort to insure that avian species return
year after year.
Management and Development of Nature Preserves
Nature preserves vary widely in size, composition and location. The degree and type of
management and development imposed on the site is dependant upon the unique qualities of
each individual site, and the goals of the regulating agency. A management plan must consider
the location, the amount of use expected, and the type of activity planned for a nature preserve.
For example, management of a preserve located in a remote wilderness area intended for hiking
only would differ from the management of a preserve located in the middle of a metropolitan area
intended to be used for environmental education. Although the specific management plan would
differ, there are many basic management concepts which may be used as the foundation for any
management plan.
In the case of the Two Ponds Wetland Preserve, the site is located in a metropolitan area
and will receive relatively high use. There will also be an environmental education program
implemented on the site. Keeping these site specific criteria in mind, several management and
development techniques will be discussed in the following sections which will be useful in the
creation of a management plan and development of interpretive trails for the Two Ponds site.
Resource Management Plan Development
An initial question which may be asked is why manage"? Why should natural areas be
regulated? If they are truly natural areas, they should be allowed to exist under completely natural
forces, without the intervention of man. Unfortunately, non-management of natural areas usually
21


results in the destruction of the site, particularly if the site is located in a densely populated area.
The Jefferson County Open Space Master Plan notes that acquired properties must be managed
and maintained or they may be more impacted by humans than before the acquisition (BRW 1989,
4). The Open Space Master Plan goes on to state that good stewardship of the land must be
promoted if there is to be reasonable assurance that the site will survive as a viable natural
habitat. Promotion of good stewardship and creating a sense of appreciation for nature is often
the best deterrent to destruction of natural areas.
The next question is "what is management"? Pigram describes resource management
as "the manipulation of elements of the resource base to maintain, enhance or even re-create
satisfying opportunity settings for various recreational pursuits" (Pigram 1983, 90). The main
thrust of this definition is to create an area which is valuable to the recreational user. Although the
user is an important consideration in management, the other half of the resource management
equation is the natural habitat and species located on a site. Faaborg states his definition of
resource management as "the manipulation of habitat or other natural factors and the control of
human disturbance to affect the populations of the managed species" (Faaborg 1988. 424). This
definition is weighted heavily towards consideration of on site species rather than user concerns.
Each of these definitions is adequate for addressing one side of the issue. But a thorough
management plan needs to consider both the user and the environment, and how they interact as
a whole unit.
Goldstein presents a definition of management which he labels ecosystem management.
His approach is closer to a management idea which encompasses both the user's concerns and
the environmental issues. Goldstein describes ecosystem management as an effort to focus on
the maintenance of an ecosystem's natural flows, structure, and cycles, rejecting the traditional
management methods which put strong emphasis on the protection of individual elements in
nature such as popular species or natural features (Goldstein 1992. 49). He continues by
22


explaining that when maintenance of natural processes and linkages become the management
goal, the ecosystem itself is valued as an object of respect and admiration. This creates the
sense that the ecosystem is worth preserving for its history, complexity, beauty and cultural
significance. By first creating this respect for ecological limits, it is then possible to adapt
consumptive activities which harmonize with natural processes. When this is accomplished, both
the environment and the user will benefit. (Goldstein 1992, 49)
Now that the concept of management has been addressed, it is time to consider the
components of a management plan. One of the most important considerations in developing a
management plan, particularly when the natural area is located in an urban environment, is to
involve the potential users of the site in the formulative stages of the plan. Those people living
adjacent to the site will most likely show the greatest interest in the management plan and
development process for the site. Ideally, the management objectives should reflect user
preferences if the plan is to receive support at the implementation stage (Pigram 1983. 82).
An example of community involvement in the creation of a management plan for
protected areas occurred in a community located on the Maria Islands of St. Lucia (Walters and
Renard 1992, 218). A management plan was needed for an area of mangroves. In this case, the
community was involved through several participatory planning activities summarized as follows:
- extensive use of local empirical knowledge of environmental issues such as coastal
currents, seasonal patterns, species composition and traditional uses of the site
- use of local skills and resources for research and data collection
- on-going redistribution of research results to local communities and resource users
through informal contacts with researchers
- concurrent public education campaigns with field trips, school programs and media
coverage
(Walters and Renard 1992. 218)
Such intense community involvement in the project generated a strong commitment to
conservation of the site. (Walters and Renard 1992, 219)
23


The St Lucia Island example supports the concept that the more people know about the
environment, the more they will appreciate and protect an area. The next step is to look at the
management process itself. Pigram has outlined one approach to the management process.
Pigram's ideas are presented in Figure 3.
Figure 3: Diagram of Management Process
(Source: Adapted from Outdoor Recreation Management: Theory and Application. Pigram. 1983)
This management process is well balanced since it considers the environment, the user and
constraints which are imposed on the managing agency. The first step of the process is to
establish a set of broad management objectives for the site. The broad objectives are then used
24


to determine the carrying capacity of the site and to select specific management procedures. The
next step is implementation of the plan. It is likely that modifications will need to be made to the
plan, for this reason continued evaluation of the plan by both managers and users is necessary to
insure that the most effective management strategies are being used.
There are several valuable aspects to Pigram's management process. This first is that it
involves input from managers, users and environmental concerns. Secondly, the plan uses a
feedback structure which allows for evaluation and modification through time. Pigram states that
close monitoring of the recreation site is necessary to chart the rate, direction and character of
changes occurring (Pigram 1983, 90). It is imperative that negative changes be detected early
before significant damage is experienced.
It is due to the dynamic nature of the environment that it is necessary to monitor changes
through time. Wiens discusses how populations tend to lag in response to habitat change (Wiens
vol. 2 1989.165). This is an important point to keep in mind when implementing a management
plan. A particular population may not change immediately upon implementation of a plan, in fact it
may take several years before changes in the populations are evident. A study was done in the
Guano Valley which looked at shrubsteppe habitat being subjected to range improvement
alterations. A large area of sage brush-dominated habitat was sprayed with a herbicide to kill the
shrubs. The dead shrubs were then removed and replaced with an exotic grass. This action
caused dramatic change to the habitat structure of the area, converting it from a shrub habitat to a
grassland habitat. Researchers expected that these changes would have an immediate effect
on the densities of breeding birds, but surprisingly it did not. For the first few years, those
species associated with sage brush habitat did not decrease, and species associated with
grassland habitat did not increase. It was not until two to three years after the habitat alteration
that the species populations changed in the expected manner. This is what Wiens refers to as
25


population lag. This study emphasizes the importance of continued monitoring of a site for many
years after any type of structural change is made to the site. (Wiens vol. 2 1989. 165)
In summary, there are several key features which will need to be included in a
management plan if it is to be successful. First, the plan must consider the user and the
environment as a unit which needs to work together for the benefit of both parties. Second, the
plan needs to have a feedback structure so that changes may be made as flaws in the plan are
discovered. Third, there needs to be a strong sense of community involvement in the creation
and implementation of the plan. Not only does this allow for smooth implementation of the plan,
but it also creates a large resource of individual managers for the site as community members
take a personal interest in protecting the area. Finally, there must be a monitoring system which
detects changes in the site over time. It makes sense that a plan for a dynamic environment
needs to be dynamic in nature to accommodate future change.
Trail Development
It is beyond the scope of this paper to create specific construction guidelines for the trails
of the Two Ponds site, but possible trail design will be examined and placement of the trail with
respect to avian habitat will be discussed in chapter 4. The following section presents some
general guidelines of trail development which relate to the development of interpretive trails.
Trails serve as a means to move people throughout a site. For this reason, well
designed trails may be used as an instrument to protect the environment by channelizing people
away from sensitive areas. However. Huddleston suggests that movement of people may be
channelized only to a limited degree (Huddleston 1980, 22). If the trail does not lead where
people want to go, they will establish their own route to arrive at a particular point. This is why it
is so important to thoroughly analyze a site, noting sensitive areas, points of interest and areas of
26


danger before creating a layout for a trail system. If trails are designed to coincide with the natural
features of the site, the risk of unplanned trails created by users will be minimized.
Many different techniques may be used to guide movement through an area. The most
common means of guiding movement is through the use of prepared surfaces such as concrete
or asphalt. Artificial barriers such as screen walls or crude fences may also be appropriate for
designating trails (Huddleston 1980, 22). Natural barriers such as rocks or logs work nicely for
trail definition because they blend well with the surrounding environment, and because they are
usually readily available on the site. Finally, directional signs and markers may be used to guide
the users. However, signs may be costly and are subject to vandalism (Huddleston 1980, 22).
The National Audubon Society offers another possible technique for designating trails and
protecting sensitive areas. The technique is referred to as situational control, and involves the
planting of brambles or barberry along a trail to keep users from wandering into environmentally
sensitive areas (Ashbaugh and Kordish 1971,28). There is a two-fold benefit to the use of
situational control. Not only does it direct the path of users, but it also provides excellent habitat
for small birds and other small mammals. (Ashbaugh and Kordish 1971.28)
The National Audubon Society has developed four points for which trail design and
construction should be based. They are as follows:
- the interpretive opportunities of the site
- the type of program intended for the site the characteristics of the land
- the needs and anticipated number of visitors to the site
(Ashbaugh and Kordish 1971.22)
If the site is analyzed with respect to each of these four points, and the information collected is
then used in the implementation of the trail system, there is reasonable assurance that the trail
design will benefit the user as well as protect the environment. The most important point to
consider in an effort to create an appropriate trail system is to examine the type of program or
27


activity intended for the site. Since the primary intent of the Two Ponds site is to create an
environmental education program, the following discussion of trail design techniques will
emphasize trail design criteria which would be useful in creating trails for these types of
programs.
The general design for formal teaching trails should consist of short, winding trails. The
most effective teaching trails are usually between one-eighth and one-quarter of a mile in length
and can be walked in one to one and one half hours by a teacher or naturalist leading a school
class. Short trails are very effective for teaching because they reduce fatigue and help to sustain
interest in the lesson being taught. Shorter trails are also advantageous for meeting time
restrictions imposed for school field trips. (Ashbaugh and Kordish 1971,21)
The most effective trail layout for teaching is a loop shape with the beginning and end of
the trail occurring at approximately the same point. Visitor flow on these trails should be in one
direction so as to avoid retracing steps and to prevent interference when several groups are
sharing the trail. Interconnecting trails are also a good design method because they allow for
choice of trial use and variations in the length of the lesson being taught. (Ashbaugh and Kordish
1971.22)
Finally, a look at trail design which optimizes bird viewing. The best trails for birding are
trails which have controlled access. This allows a means by which to regulate disturbance of
prime avian habitat, giving the visitor a greater chance to see birds along the trail. The trail
should pass through a variety of habitats which are likely to support a variety of birds. The edge
or interface between habitats generally contain the most productive areas for birding. Hence, it is
advantageous to place trails where these areas may be readily observed. (Fogg 1990,161)
28


Concepts of Interpretive Programs
Freeman Tiiden is considered to be the Father of Interpretation" (Jubenviile et.al. 1987,
166). He worked a great deal with forming many of the basic concepts associated with
interpretive programs and environmental education. Tiiden wrote that the chief aim of
interpretation is not instruction, but provocation (Jubenviile et.al. 1987,167). He based his
concepts on the idea that interpretation of the environment was a means to excite curiosity and to
open a person's mind. The hope is that through learning about nature a greater appreciation for
the environment will immerge. The National Park Service Administrative Manual contains the
following statement:
Through interpretation, understanding,
Through understanding, appreciation,
Through appreciation, protection.
(Wallin 1976, 332)
These three statements very succinctly present the backbone of the interpretation concept.
Just as there are several ways to create a management plan for an area, there are also
many different ways to approach the development of an interpretation program. In his book Park
Planning Guidelines. George Fogg has outlined what he sees as the objectives of an interpretive
program. These objectives combine both the needs of the visitor and protection of the
environment. Fogg's objectives of interpretive programs are as follows:
- to help the visitor enjoy the park through better understanding and appreciation of
purposes and resources
- to promote intelligent use of the park resources and facilities through educational
programs and activities
- to help visitors develop a sense of responsibility concerning conservation and use of
natural resources
- to instill a sense of appreciation for natural and man-made resources of the park in
order to reduce willful destruction and vandalism of park property
- to help increase knowledge and understanding of mans role in the natural environment
29


- to help visitors understand, enjoy, appreciate, and develop respect tor his environment
- to develop a knowledge and understanding of ecology
- to help visitor develop an interest in past history
(Fogg 1990,25)
The next step is to create the interpretive program for a particular site. Jubenville. Twight and
Becker offer the following steps for interpretive program planning:
- inventory what resources are available on the site
- select the pertinent environmental themes to be presented
- establish specific programs and activities to fully capture themes, and develop
necessary infrastructure to carry-out the programs
- hire personnel to conduct the programs
- train the personnel on howto present programs
- monitor the presentations
(Jubenville et.al. 1987,167)
Although interpretive programs are extremely useful for teaching visitors about the environment,
they should not be a replacement for traditional teaching through schools. Instead, the
interpretation center should be a supplement to support environmental concepts being taught in a
traditional setting. (Ashbaugh and Kordish 1971.29)
The primary goal of the interpretive program is to allow people to learn from nature.
Interpretive programs are particularly important in urban areas where the average person's
contact with nature is minimal. The Two Ponds site is a perfect opportunity to incorporate an
interpretive program. Using the general guidelines presented in this section, suggestions for the
Two Ponds interpretive program will be given in Chapter 4.
30


CHAPTER 3
STUDY SITE: THE TWO PONDS WETLAND PRESERVE
Location of Site
The study site is located in Jefferson County, Colorado, in the city of Arvada. The area is
part of the Denver metropolitan region. The Two Ponds Wetland Preserve is approximately 82
acres situated in the southwest corner of 80th Avenue and Kipling Street (see Figure 4). The fact
that the Two Ponds Wetland Preserve is located within a metropolitan area of approximately 1.6
million people makes it a unique commodity and valuable asset to the surrounding area.
(USFWS 1992.1)
Qirreni Land Use and Ownership.oliha Site
The Two Ponds Wetland Preserve contains a very small amount of residential and
commercial development. This development consists of a few homes and a veterinary clinic
located on the northern boundary of the site (see Figure 5). There is a minimal amount of grazing
by a few horses which occurs on the grasslands to the west of the Farmer's Highline Canal. The
site is transected by three water delivery canals, the Croke Canal, the Farmer's Highline Canal,
and the Church Ditch. These canals supply water to surrounding municipal and agricultural users
(USFWS 1992.12). Local residents utilize the Croke and Farmer's Highline canals as walking
and jogging paths, and occasionally the Two Ponds site is used for educational activities by local
schools. All activities combined, the site serves less than 100 people per year under the existing
ownership (USFWS 1992,12). These activities cause minimal impact to the area due to the low
number of people using the site. The USFWS projects that non-management of the Two Ponds
31


Figure 4: Vicinity Map for Two Ponds
Wetland Preserve
0 12 3
1 ___1____i i
Scale: 1"= 1.75 miles


(Souroa: Adapted tom "Dacttxjn Docurrvart: Two Pond* Wetand Prataiva*. USFWS. 1992.)


80th Avenue
Preserve Boundary ' ' Irrigated Grassland
Residential / Commercial Use ! Cattail Wetland
o Trees o Open Water Wetland (Pond)
T Willows Lawn and Odd Areas
sk Grassland
Figure 5: Existing Land Use and Vegetation
(Source Adapted from Tiecaston Document Two Pond* w

area would result in a substantial amount of residential and commercial development. Under
current zoning, up to 160 homes could be built on 70 acres of the site. (USFWS 1992, 2)
Figure 6 shows the existing landownership of the Two Pond Wetland Preserve. The
USFWS is actively seeking acquisition of all eight parcels of land. At this time, the USFWS has
already secured fee title to tracts one and two. According to Harvey Wittmier, Acquisitions
Biologist for the USFWS, tract three will be purchased as soon as money is appropriated by the
USFWS, and tracts four and six will be donated to the USFWS in the near future. Wittmier
described tract five as being close to an agreement for purchase. Tracts seven and eight are of
most concern according to Wittmier. He felt that without these tracts of land, the viability of the
Two Ponds site as a natural refuge would decrease immensely. These two tracts contain the
majority of the natural habitat needed to support the wildlife on the site. Negotiations between
Lutheran Medical Center and the USFWS are currently in progress concerning the purchase of
tracts seven and eight. The USFWS considers fee title ownership as the most practical way to
stop development, protect the habitat, and manage the site as an environmental education center.
(USFWS 1992.1)
34


Esfly Road FVW
Ji
80th Avenue
Trad Ownership Acreage
1 USFWS 12.6
2 USFWS 9.6
3 1 si Bank of W. Arvada & Arlene Howard 49
4 City of Arvada 7.1
5 Robert Cohen 5.9
6 Oberon Heights Water & Sanitation Distnct 1.2
7 Lutheran Medicai Center 35.0
8 Lutheran Medical Center 5.7
0 400 feet
1 ___I____I____I____I
Scale: V^AOO1
Preserve Boundary
Tract Number
Figure 6: Existing Landownership
(Source: Adapted from 'Deration Document: Two Pond* W stand Present'. USFWS. 1992.)
Pond


Proposed Land Use of Site
The USFWS has classified the Two Ponds Wetland Preserve as an area of high priority
for acquisition for the following reasons:
- On a national level, the USFWS has started a program to increase urban habitat
conservation and environmental education.
- Natural areas such as Two Ponds are becoming increasingly rare in the Denver-
Boulder metropolitan area.
- The close proximity of the site to local schools makes it a major benefit to
environmental education programs conducted by the schools.
- The site is an excellent representation of wildlife and wildlife habitats found elsewhere
on the Front Range.
(USFWS 1992.1)
The environmental assessment produced by the USFWS outlines four alternatives for the Two
Ponds Wetland Preserve. In brief, the alternatives were as follows:
1. No action alternative
2. Acquisition of the entire 80 acre site by using fee title and other acquisition methods
3. Acquisition of 13 acres of the site using fee title
4. Acquisition of all or part of the 80 acres by other organizations
(USFWS 1992,1)
The preferred alternative by the USFWS is alternative number two, acquisition of the entire 80
acres using fee title and other acquisition methods. Acquisition of the entire site would allow it to
be included as a unit of the National Wildlife Refuge System. The purpose of such a refuge, as
stated by the USFWS. would be to protect existing wildlife values, migratory waterfowl, passerine
birds and mammals found on the site. The area would also provide for environmental education
programs with an emphasis on the inherent values of wetlands and wildlife in an urban area, as
well as provide interpretive facilities and opportunities related to wildlife viewing and enjoyment
for the visitor. (USFWS 1992, 2)
36


Alternative number two. referred to by the USFWS as the Site Management Plan, is
presented graphically in Figure 7. The ponds closest to 80th Avenue would support the majority
of the educational and public use activities. A small, indoor classroom would be constructed and
utilized by school groups to study such topics as wetland functions and values, basic elements of
wildlife, or functions and systems in ecology. The USFWS plans to develop approximately 1.5
miles of trails on the site. The trails would be two self-guided, interpretive trail loops. One of the
trail loops would connect with the Croke Canal where the Arvada Parks and Recreation
Department has planned to construct a trail. There would also be an elevated boardwalk
constructed which would jut into a portion of the wetlands area. This amenity would enhance the
educational and interpretive opportunities of the visitors by allowing them to take a closer look at
the wetland systems. The USFWS would keep the area southwest of the Farmer's Highline Canal
closed to the public and maintain the area as natural grassland and open space. (USFWS 1992,
2-4)
Matt Gay. Public Use Department for USFWS, explained that the interpretive program will
be based on environmental lesson plans which will be available for use by teachers leading field
trips on the site. The lesson plans will serve as a guide for the teachers as they lead their class
through the preserve. Gay said that part of the Two Ponds interpretive program would be to hold
environmental workshops for the teachers which would like to use the site for environmental
education lessons. The workshops would instruct the participants about basic concepts and
systems of nature, and explain how to use the lesson plans prepared by the USFWS. This is a
creative and innovative approach to interpretive programming. The involvement of teachers in the
interpretive process is a great idea because it educates a very influential segment of sociely
about the environment. If teachers are environmentally knowledgeable, there is a greater chance
that they will pass basic concepts about nature on to their students. This wiil help to move
communities one step closer to being knowledgeable and respectful of the world around them.
37


Kipling Street
80th Avenue
Primary Environmental Education Area
----------Possible Interpretive Trails
1 1 Wildlife Sanctuary
Indoor Classrooms. Restrooms and Parking
Figure 7: Site Management Plan Alternative No. 2
(Source: Adapted from 'Decision Document Two Ponds Wefland Preserve", USFWS. 1992.)
Pond


CHAPTER A
ANALYSIS OF TWO PONDS WETLAND PRESERVE
Habitat Resources of Site
The variety of natural resources located on the Two Ponds site make it a very valuable
parcel of land. The resources are valuable both to humans and animals. The primary benefit the
site provides for humans is the resource of open space. Increased urbanization has made open
spaces a rare commodity within metropolitan areas. The Two Ponds Wetland Preserve serves
as an instrument to satisfy mans innate need to be a part of nature by providing urban dwellers in
the surrounding metro area with a place to experience nature. The other primary resource which
is of benefit to humans is the sites potential as an environmental education center. As a
supplement to traditional education programs, the site provides the opportunity for hands-on
learning by students.
The natural resources of the site may be broken down into three major categories,
upland, wetlands, and open water. The upland portions of the site cover approximately 63.5
acres, the wetlands approximately 15.6 acres, and the open water covers about 3.0 acres
(USFWS 1992. 9). Figure 5 indicates the general location of the upland, wetland and open water
resources.
According to an inventory conducted by the USFWS, the following is a breakdown of the
natural resources found within each of the three resource categories of upland, wetlands and
open water. The vegetation found in the upland portions of the site is dominated by brome grass
intermixed with alfalfa. On the hilltops and knolls, there are several mid-grass prairie species
such as needle and thread grass. Yucca and rabbitbrush are also found in these dryer grassland
areas. The USFWS contracted the Colorado State Forest Service to do a tree inventory on the
39


site. Approximately 25 different tree species were identified, and a total of 360 trees were
counted. (USFWS 1992, C1 -2)
The wetland habitat on the Two Ponds site contain large tracts of cattails. Along the
edges of the cattails there are sand bar willow, Russian olive and cottonwood trees. Each of
these species are identifiers for wetland habitats. The maintenance of the wetland areas is of
prime importance due to the wide variety of species, both plant and animal, that these portions of
the site support. More research needs to be done to explore the water table for the site, and to
determine if the wetland areas are dependant upon water which seeps from the canals. If this is
the case, lining of the canals by the ditch companies would be detrimental to the existence of the
wetland habitat on the site.
The open water on the site consists of three main ponds located on the eastern side of
the site, and one small pond found in the northwest quarter of the site (refer back to Figure 5).
Submerged aquatic vegetation is present throughout the ponds, and ornamental trees such as
weeping willow and poplar have been planted along the edges of the larger ponds (USFWS
1992,10). The ponds on the site are a unique resource which allow for many varieties of
waterfowl to use the site as a feeding ground.
It is due to this mix of natural resources that the site is able to support such a wide variety
of wildlife. The wildlife on the site ranges from mammals to reptiles and amphibians to birds.
There have been sitings of red fox, muskrat, beaver, raccoon, vole, coyote and deer. The ponds
support painted turtles, snapping turtles, bull frogs and leopard frogs (USFWS 1992, D3). Birds
represent the largest number of different animal species found on the site. The site's varied
resources provide optimal habitat for the numerous avian species residing in the area. Now to
look at how specific resources meet the needs of the birds utilizing the site.
40


As was discussed in Chapter 2 under Habitat Resources, a resource is not always that
which is consumed by the user. Aside from food sources, there are spatial, nesting and perch
site considerations when analyzing an area for suitability for avian species.
First, a look at the obvious resource of food. The Two Ponds site has an abundant and
readily available food supply for several different species of birds. The open fields provide
excellent habitat for small mammals such as voles and mice which serve as the main food supply
for the many hawks that frequent the site. Seeds and berries are abundant in the brushy habitats
and serve to support small passerine birds. The ponds provide the necessary food resources to
support a variety of waterfowl. Submerged vegetative matter as well as insects, small fish and
amphibians serve as food for ducks, herons and kingfishers. There is also an abundance of food
for waterfowl located in the canals. However, the canal habitat as a food source is not a
guaranteed resource. There is a possibility that the ditch companies will dredge the canals as a
maintenance technique. This would eliminate much of the vegetation and aquatic life which
serves as a food source for many avian species. The USFWS has stated in their Decision
Document for the Two Ponds area that they will make an effort to work with the ditch companies
in order to minimize disruption and loss of valuable habitat. (USFWS 1992, 4)
The next resource to be considered is that of spatial needs. The size of the site,
approximately 80 acres, provides ample space for the coexistence of many species. Specific
territories are generally only developed by those species which are nesting on the site.
According to the USFWS Decision Document for the Two Ponds site, only 11 of the 63 species
identified on the site have been confirmed as nesting on the site (USFWS 1992, D2-3). Hence, a
majority of the species use the site as a feeding ground or resting point while migrating through
the area. Species which use the site primarily as a feeding ground will be spatially limited by the
abundance and availability of their particular food source.
41


The nesting resources of the site vary widely. Of the 11 species which have been
confirmed as nesting on the site, the nest types range from those which buiid cup nests, those
which use tree cavities, those which nest in cattails and pond edges, and those which nest in mud
banks. There are a sufficient number of trees to supply nesting site for species which build cup
type nests. This includes both smaller trees, used by European Starlings (Sturnus vulgaris)\ax
nesting, and larger trees, used by Swainson's Hawks (Buteo swamsoni) for nesting. The cattails
and pond habitat provide nest sites for Red-winged Blackbirds {Age/aius phoeniceus) and
Mallards (Anasp/atyrhynchos). Many of the older cottonwood trees have cavities suitable for
nesting by the Downy Woodpecker (Dendrocopospubescens) and the Common Flicker
( Co/aptes auratus). The banks of the canals are perfect nesting areas for the Belted Kingfisher
(Megaceryle a/cyori) which burrows a hole in the ground to create a nest.
The final resource to be considered with respect to avian species is the availability of
perch sites. Perch sites are used in a variety of ways by different species. Song birds use the
branches of smaller trees and bushes as perches to vocalize their characteristic melodies.
Songs are used to attract mates as well as define territories. The branches of the larger trees are
used by hawks and other large birds to scan areas for prey. The Two Ponds site has an ample
supply of trees located along the Church Ditch which are adjacent to the largest expanse of
grassland. This is a prime location for hawks to perch and hunt for small mammals living in the
grasslands.
Overall, the Two Ponds site has a sufficient resource base to serve both humans and
animals. The key is to manage the site so than both parties may use the site without causing
adverse affects to the other. This topic will be discussed in the section on Suggestions for
Management of the Site. The next section will analyze the structure of the habitat found on the
Two Ponds site.
42


Habitat Structure of Site
On a macroscale, the basic structure of the Two Ponds site is that of an island. It is an
island of natural habitat surrounded by a sea of urban development. Figure 8 is an aerial view
taken from the northeast corner of the site looking southwest. The isolation of the site by
residential construction is very apparent in this photograph. Because of the sites isolation from
other natural habitats, the factors of Island Blogeographic Theory discussed in Chapter 2 under
Habitat Structure apply to the Two Ponds area. Many species of birds found on the site fit the
description of being good colonizers and not very habitat specific. This includes species such as
Starlings (Stumus vulgaris). Robins ( Turdus migratorius). House Finches ( Carpodacus
m&dcanus). Pigeons ( Co/umba iivia) and a variety of sparrows.
However, the Two Ponds site is also used by species which are much more habitat
specific. The variety of habitats found on the site are apparent when the site is examined at a
microscale. Figure 9 presents a breakdown of nine specific habitats which are present on the
site. The specific habitat categories include open water, open country and grassland, marsh,
grove, brushy open country, forest edge and forest, and thicket. The patchiness of the different
habitats is apparent in the graphic depiction in Figure 9. This patchiness creates an abundance
of ecotones, the transition zone between habitat types. This is an advantage to the site since
ecotones have been shown to contain a greater number and higher diversity of avian species.
The problem with the intense patchiness of the site is that the patches may be too small to
support some species. For instance, even though the tree stands on the site have been classified
as forest habitat, they are not large enough to support interior forest species such as the Veery
( Catharus fuscescens), Swainson's Thrush ( Catharus ustu/atus) and the Gray-cheeked Thrush
( Catharus minimus). The trees stands are more correctly described as forest edge habitat.
43


View of Two Ponds Wetland Preserve looking southwest from the northeast comer of site.
Preserve Boundary
Figure 8: Aerial View of Two Ponds Wetland Preserve
(Photograph courtesy of M C. Redmond. 1992.)


Kipling Street
s.
$
LU
£=
CZH
mg
Open Water
Open Country / Grassland
Marsh
Grove
Brushy Open Country
Forest Edge / Forest
Thicket
0 400 leet
1 ___I____I____I____I
Scale: 1" = 400*

Figure 9: Habitat Structure of Two Ponds Wetland Preserve
(Base map from "Decision Document: Two Ponds Wetland Preserve", USFWS. 1992.)
Pond


In Figure 10. the 63 avian sDecies identified on the site have been grouped by the
habitats in which they are most likely to be found. Although there is a sufficient amount of overlap
between the habitat type needed by each species, three general categories of habitat may be
derived from the information in Figure 10. The first group contains those birds found mainly in
forest, forest edge, grove, thicket and brushy open country habitats. The next group of species
reside primarily in open country and grasslands. The third set of birds occupy marsh and open
water habitats. Of the three general classifications, only those species characteristic of marsh
and open water are not associated with residential and urban habitats. Therefore, these species
are the most dependent on the sites marsh and open water resources.
In general the site contains a good mix of habitat resources and suitable habitat structure
to support a viable avian population. Suggestions on how to manage the site to maintain and
enhance the avian habitat are discussed in the next section.
46


Forest Brushy Open Open Grass- Open Residential/
Forest Edge Thicket Grove_______________________Country Country land Marsh Water Urban
White-breasted Nuthatch
Bohemian Waxwing Grosbeak
Downy Woodpecker
Black-capped Chickadee
Yellow-rumped Warbler
Broad-tailed Hummingbrd
Blue Jay
Chipping Sparrow
Darit-eyedJunco
Whitecrowned Sparrow
Song Sparrow
Yellow Warbler
lazi* Bunting
Amencan Goldfinch
Pheasant
Black-billed Magpi
Common Grackle
Common Nighthawk
House Wren
Common Flicker
Great Homed Owl
Mourning Dove
Northern Oriole
Sharp-shinned Hawk
Red-tailed Hawk
Amencan Robin
Amencan Crow
Turkey Vulture
Brown-headed Cowbird
Western Kingbird
Domestic Pigeon
Figure 10: Grouping of Avian Species by Habitat Type
(Habit* information from An Audubon Handbook: Western Birds. Farrand, 1988.)


Western Meadowlark
Remiginous Hawk
Swainson's Hawk
Rougtrieqged Hawk
American Kestrel
House Rncti
European Starting
House/English Sparrow
Brewers Blackbird
Ring-billed Gun
Forest
Forest Brushy Open Open Grass- Open Residential/
Fdqe Pricket Grove Spuntrv Country 'and Marsn Water Hrban
free Swallow
Cuff Swallow
Bam Swallow
reflow-headed Blackbird
Redwmgod Blackbird
kddeer
Canada Goose
American Widgeon
Piedbillod Grebe
Western Grebe
Redhead Duck
Wood Duck
Bluewinged Teal
Sandpiper
Belted Kingfisher
Common Snipe
Great Blue Heron
Black-crowned Night Heron
Mallard
Bufflohead
Common Goldeneye
Ringnecked Duck


Suggestions for Management of the Site
The purpose of this paper is not to provide the specifics of the management plan to be
implemented by the USFWS. Rather this paper suggests a basic outline of key items which
should be included in the final management plan, and to present some specific management
tactics which relate to avian habitat on the Two Ponds Wetland Preserve.
The overall tone of the management plan should project a sense of cooperation between
the users and the environment. This means that concern for the environment is just as important
as the concern for user satisfaction. This is an important concept since the objectives for the site,
as stated by the USFWS, are to manage the site as a wildlife refuge as well as manage an
environmental education center. To meet these two objectives, the site has been divided, limiting
human activity to the area east of the Croke Canal and maintaining the land west of the Crake
Canal as wildlife sanctuary (refer back to Figure 7).
In order to meet the needs of the users, there must be continued involvement of the
community in the management process. This may be achieved through public meetings,
distribution of material explaining the management objectives for the site, and hikes lead on the
site to familiarize the community with the resources available to them. All of these methods of
public involvement will allow for opportunities to educate the public about the site, as well as
allow the public to ask questions and offer input for the proposed program.
In an effort to protect the environment, there must be a significant amount of research
done on the site before implementation of the environmental education program. A thorough
analysis of the site's resources must be executed so that an initial state assessment may be
made. This base information will serve as a comparison for future assessment, and allow for a
means by which to monitor both positive and negative changes occurring on the site.
Once an initial inventory is complete and the activity level of the proposed environmental
education program is determined, the carrying capacity of the site should be assessed. This
49


value should then be used when managing the intensity of use on the site. Theoretically, the
carrying capacity should be the upper limit of the number ot users which the site can
accommodate without experiencing damage to habitat. In addition to environmental concerns,
the carrying capacity should also consider user satisfaction in determining the greatest number of
visitors the site can handle at any given time without creating an overcrowded feeling.
The carrying capacity gives a guideline by which to measure acceptable use. However,
many times the carrying capacity for a site is exceeded. In fact, as an area becomes more
popular it is most likely that the carrying capacity will be exceeded on a regular basis, it is at this
point that either the management plan must be altered to regulate higher use, or the site must be
enhanced so that it may accommodate increased use. The best solution would be to incorporate
both management changes and site enhancement in an effort to protect against damage to the
environment due to increased use.
Site enhancement techniques might consist of planting heartier species of ground cover
in areas where high use creates parcels of bare ground, subjecting the area to increased erosion.
However, care must be taken in the selection of introduced vegetation. The plants must be
compatible, preferably native species, with the existing vegetation on the site.
Management changes might include increased signage to protect sensitive areas, or
enhancing the environmental education program to include a stronger emphasis on the
importance of treading lightly in natural areas. Use of trails could be alternated to allow for a
resting and re-growth period for the vegetation experiencing damage along the trails. Another
technique to control use on the site might be to require that school groups schedule a specific
time to use the site. This would allow the managing agency to regulate the number of groups
using the trails at any given time, giving reasonable assurance that the carrying capacity of the site
is not being exceeded. Not only will scheduling of groups protect the environment, but it will also
increase user satisfaction by keeping the site from being overcrowded. Too many groups using
l


the site at one time creates a larger disturbance which in turn greatly reduces potential to view
wildlife.
The plan must also take into consideration that not only will the natural environment of the
site change, but the educational program created for the site will also change. Hopefully, the
environmental education program will grow over the years as more teachers and students
become involved in learning about the environment. However, as discussed earlier, growth will
need to be kept in check by making changes in the management plan or by enhancing the site to
accommodate increased use.
Overcrowding is particularly detrimental to bird watching opportunities. Because of the
highly mobile nature of birds, even low levels of disturbance will make it difficult to observe and
identify some species. One solution could be to teach the users to identify birds not only by site,
but also by sound. This training could be incorporated into the lesson plans provided to teachers
planning to use the site for environmental lessons. A cassette tape with a recording of the calls
and songs of the most common birds found on the site could be used as part of the
environmental classes taught in the schools. Then when the students arrived at the site, they may
be able to identify some of the birds by their songs. Using this approach will also aid in making
the students more aware of the many other sounds of nature, broadening their use of the senses
to experience the site.
With respect to the management of natural resources related to avian species, the most
important point is to minimize destruction of the unique resources found on the site. These
resources include the old trees which provide sites for cavity nesters as well as perches for large
birds, and the open water and marsh areas which provide habitat for waterfowl. Without these
habitats the variety of avian species on the site would be greatly reduced.
As mentioned previously, the management plan for the site must incorporate a
monitoring system so that both positive and negative changes may be detected. All parts of
51


nature are dynamic and change over time. In the case of the Two Ponds site, the proposed
environmental education program introduces a non-natural factor in the equation of dynamic
change. The plan must contain a feedback mechanism so that it can be adjusted to meet future
needs of the user and the environment. For this reason, the managing agency must remain open
to suggestions on howto improve the use and management of the site.
When changes in habitat are detected, it is important to assess which species will be
affected by the changes. Figure 10 will be a useful tool in assessing which avian species will be
affected by specific habitat changes. Conversely, monitoring changes in avian populations will
allow for changes in habitat to be noticed. For instance, if there is a significant decrease in the
number of Red-winged Blackbirds (Age/a/usphoen/ceus) on the site, it may be an indication that
there has been a change in the wetland and marsh habitat. An investigation of why changes are
occurring should then be done to determine if it is a result of natural fluctuations or if the changes
are a result of overuse by humans. At this point, an informed decision may be made on how to
mitigate further damage to the specific habitat.
Finally, an innovative suggestion for the management plan would be to apply Geographic
Information System (GIS) techniques to aid in the management of the site. The site is not
excessive in size, and a base map could be created in GIS relatively easily. The layers of the GIS
program could include a base map, a contour map. vegetative information, trail corridors,
hydrologic information, specific habitat designation, and specific nest sites for birds just to name a
few. The GIS program could then be used to track changes in the site over time as new data is
input into the database year after year. For instance, it would be possible to detect population
fluctuations in birds by tracking the location and number of nesting sites from year to year. From
this information it may become apparent that heavy use of a particular area is causing a decrease
in nesting success. The management of that particular area may then be altered to mitigate
further disturbance. The potential advantages of computer mapping through GIS are numerous.
52


Hopefully, this technique will be implemented in the future to aid in the management of the Two
Ponds Wetland Preserve.
Suggestions for Trail Design and Placement on the Site
The specific construction guidelines for the trails on the Two Ponds site will be
determined by the USFWS. not by this paper. This section suggests design and placement of the
trails given their proposed use for environmental education purposes as well as specific
suggestions for trail placement which will enhance bird viewing opportunities.
The majority of use on the trails will be by school groups lead by their teachers. The
design of the trails should reflect the needs of this target group. The trails should be easy to walk,
no steep grades, and wide enough to keep the group together and within hearing range of the
instructor. Narrow trails only allow for single-file formation, making it difficult for the last person in
the line to hear the instructor. The trail length should be such that it takes and instructor with a
group about 1 to 1.5 hours to walk the trail. As shown on Figure 7. the USFWS plans to use
looped trails on the site. Looped trails are good for interpretive programs because they allow the
group to start and end at approximately the same point, and they also make it easier to keep
traffic flowing in one direction.
One of the primary goals of an interpretive program is to educate and inspire curiosity
about the environment. To accomplish this, the interpretive program should provide a variety of
information which covers a diverse range of topics. For this reason, the trails on the site should
pass through as many different habitat types as possible to provide a wide range of experiences.
Trail placement in the area east of the Croke Canal will allow the trails to pass by almost all of the
habitats found an the site; open water, wetland, grassland, open country, brushy open country,
forest edge, and grove. This is one of the many reasons why this portion of the site is ideal for the
trail system. Another reason lies in the fact that this is the most secure portion of the site with
53


regard to USFWS ownership of land. Tracts one and two have already been purchased by the
USFWS. and tract three will be purcnasea as soon as money is allocated for land acquisition on
the Two Ponds site (refer back to Figure 6). Additionally, this portion of the site is separated from
the remainder of the Two Ponds Preserve by the Croke Canal. The canal barrier will aid in
keeping visitors away form the remainder of the site which will be designated as a wildlife
sanctuary, (see Figure 11)
The suggested trail placement for the Two Ponds site is shown in Figure 11. The trails
should be loops which start at the proposed indoor classroom area. The suggested trail plan
consists of three different trail loops. The trail on the east side of the site, trail number one. will
pass through forest edge, open water, wetland, brushy open country, grassland and open country
habitats. This segment of trail should include a side trail which juts into the wetland habitat to give
the users a closer look at the wetlands, while at the same time controlling activity in this sensitive
area. At the end of this small segment of trail which projects into the wetland habitat, there should
be an observation platform. The platform would serve as an area to turn around, as well as allow
for visitors to stop and view the wildlife of the wetlands close-up. The southern most point of the
trail should have a segment of trail which connects the loop to the Croke Canal trail. This will
allow for access to the second loop by traveling on the Croke Canal. Otherwise the visitor must
return to the starting point to reach the second trail.
Trail number two is designed specifically for observation of waterfowl and other birds
found close to the third pond. This pond is located at an elevation which is about 15 feet higher
than the other two ponds. Therefore there is a slight grade as one approaches the pond. This
causes the pond to be out of view until walking up a small embankment. This is an ideal place to
position a bird blind because the hiker is able to approach the area without being noticed by
waterfowl on the pond, reducing the chance that the birds will flush from the approach of humans
(see Figure 11). From this point the trail turns northwest, away from the pond and the bird blind.
54


EsOy Road FVW
80th Avenue
*
O
Primary Environmental Education Area
Suggested Placement of Interpretive Trails
Wildlife Sanctuary
Indoor Classrooms. Restrooms and Parking
Bird Blind
Observation Platform
Trail Number
Figure 11: Suggested Traii Placement for two Ponds Wetland Preserve
(Base map from "Decision Document: Two Ponds Welland Preserve". USFWS. 1992.)


in an effort to further reduce disturbance of waterfowl on the pond. The trail loops through
grassland habitat and then returns to the point of beginning. As with traii number one, there is a
connector segment of trail leading to the Croke Canal trail.
Trail number three is the largest loop and incorporates both trails one and two. More
than anything, this trail would serve as a connector trail between the two smaller loop trails. The
suggested trail placement would allow for groups to chose from a wide range of trail length. This
adds variety in the lessons which may be taught on the site. For example, a group af second
graders may just use trail number one. keeping the hike and the lesson short. On the other hand,
a group of seventh graders may use a combination of trails number one and three so that the
lesson may be more intense and cover a greater amount of material. This trail layout gives the
teacher a great deal of freedom in creating their lessons for use on the Two Ponds site.
One enhancement to avian habitat which could be used on the site is the placement of
nest boxes along trails. There are both positive and negative factors associated with the use of
nest boxes along trails. On the positive side, the nest boxes would serve as a teaching
mechanism. The visitors would be able to observe nest building and clutch rearing activities.
Also, the correct type of nest box would aid in attracting species which otherwise would not be
found nesting on the site. On the negative side, nest boxes are expensive to establish and
maintain. Very often nest boxes become occupied by common birds such as Starlings (Sturrws
vulgaris) and House Sparrows (Passer damesticus) instead of the species which they are
intended to attract. The USFWS will need to determine what the goals are in the area of nesting
birds. If the desire is to increase the number of birds nesting on the site, then nest boxes are one
way in which to reach that goal. However, if the goal is to maintain a habitat that is used primarily
as a feeding or resting ground for birds, nest boxes would probably be an unnecessary expense.
Once the trails are in place, effects on habitat adjacent to the trails should be monitored
closely to detect any damage which may occur. This information should then be used in the
56


feedback loop of the management plan to insure that changes will be made in trail use to mitigate
further damage.
Trails are one of the most important tools for an interpretive program. Where the trails
lead people will affect the quality of the hiker's experience. Hopefully, the final trail design and
placement for the Two Ponds site will incorporate some of the specific suggestions presented
which are directed towards the successful viewing of birds.
57


CHAPTER 5
CONCLUSIONS
The Two Ponds Wetland Preserve is a unique site located within a metropolitan area.
The site provides an opportunity for urban dwellers to experience natural systems in an open
space which is very close to their homes. Open spaces within metropolitan areas are important
tools in the effort to educate people about the environment, which in turn will promote an
appreciation for the environment. Hopefully, the appreciation people develop for the environment
will result in a greater sense of respect and protection of natural systems. These factors make the
Two Ponds site a critical area for preservation.
The USFWS has accepted the challenge of trying to preserve this site by initiating the
creation of a management plan and interpretive program for the site. This paper has addressed
the many steps that need to be taken in order to produce a management plan and trail system
which benefits the environment of the site and the users of the site. In particular, this paper
addressed how the avian habitat and bird species of the site should be considered in the
development of the area.
By analyzing the Two Ponds habitat resources and structure, it was found that the site has
an abundance of resources which can support both common bird species and bird species not
typically found in the surrounding area. The site's ability to attract uncommon species make it
necessary to create a management plan and trail system which considers these special features
of the site which attract uncommon species. These special features include the ponds, the
wetland habitat and the old growth trees.
There were several suggestions made for the proposed management plan. In general
the plan should consider both the environment and the user's satisfaction level. The public, in
58


particular the surrounding community, should be involved in the development process of the
management plan. This will allow for smoother approval of the plan when it is presented for
public comments. The management plan should have a feedback mechanism to allow for input
from citizens using the site and managers of the site. This allows for changes to be made in the
plan as problems are discovered.
Continued monitoring of habitat and populations over time will be necessary to detect
changes on the site. If habitat critical to avian species undergoes a change, the species
particular to that habitat should be watched closely for negative response to the change. If there
is a damaging effect on the species population, changes should be made in the management
plan to mitigate further damage.
The placement of trails should be considered carefully. The area to be used for the trails
is a relatively small portion of the site. For this reason, placement the trails is critical if the
experience of the visitors is to be optimized. The trails should pass through as many different
habitat types as possible to allow for a wide variety of experiences. Two features which would
enhance the observation of birds are a bird blind and nest boxes along the trails. Trails should
lead away from sensitive habitat, and should lead to areas of interest such as a bird blind.
The key purposes of the Two Ponds project is to preserve a wilderness area and create
a program through which people may learn about the environment. This paper presented some
of the general concepts in management and trail development of natural areas. Hopefully, the
specific research done on the avian habitat of the Two Ponds site will aid in the creation of an
environmental education program and trail system which will give adequate attention to the birds
on the site, and the enjoyment that may be found by learning about and observing birds.
59


REFERENCE LIST
Ashbaugh, Bryon L. and Raymond J. Kordish. 1971. Trail Planning and Layout.
New York. NY: National Audubon Society, Inc.
BRW, Inc. assisted by Urban Edges. 1989. Jefferson County Open Space Master Plan. Golden.
CO: Jefferson County Open Space Program.
Cody, Martin L ed. 1985. Habitat Selection in Birds. Orlando, FL: Academic Press. Inc.
Comely, John, Migratory Waterfowl. Matt Gay, Public Use, Wayne King. Regional Refuge
Biologist, and Harvey Wittmier, Aquisition Biologist. 1993. Interview by author. 19 March,
Denver. U.S. Fish and Wildlife Service, Denver, CO.
Eidsvik, Harold K. 1992. Strengthening Protected Areas Through Philosophy, Science and
Management: A Global Perspective. In Science and the Management of Protected
Areas, ed. J.H. Martin Willison, Soren Boundrup-Nielsen, Clifford Drysdale, Tom B.
Herman. Neil W.P. Munro and Tom L. Pollock. 9-18. New York, NY: Elsevier Science
Publishers B.V.
Faaborg. John. 1988. Ornithology. An Ecological Approach. Englewood Cliffs, NJ: Prentice
Hall.
Farrand, John Jr. 1988. An Audubon Handbook: Western Birds. New York, NY: McGraw-Hill
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