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A Review of the Use of GIS in the Field of Wildlife Management

Mike Stoever Geographic Information Systems (GIS)

Johns Hopkins University 12/05/2016

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ABSTRACT In the field of wildlife management, ecological principles are employed to protect wild

floral and faunal species in ways that are equally beneficial to both the habitats upon which they

rely and the human populations that surround them. In such a spatially focused discipline, GIS is

a vital tool for wildlife managers. It allows them to gain a deeper understanding of what drives

the movements of targeted species, enabling the implementation of more efficient, site- and

species-specific strategies and actions. This paper details the application of GIS technology

across the discipline through a review of the current literature and practical examples from the

field. These examples include how GIS is used to model wildlife corridors; how GIS is being

used to preserve biodiversity and protect endangered species and their habitats; the ways that the

U.S. Fish and Wildlife Service uses GIS; and how GIS is used by the Minnesota Department of

Natural Resources to manage and monitor wildlife. In each example, it was found that GIS

played an essential role in providing a clear understanding of the spatial relationships between

target species and their habitats, informing management plans through overlaying spatial

distributions of target species and the various components (soil type, vegetative type,

precipitation, etc.) of their habitats and protected areas, a technique known as gap analysis.

Additionally, it was shown that the effectiveness of GIS in wildlife management is highly

dependent upon 1) the quality and quantity of the spatial and attribute data comprising the

system and 2) a firm understanding of the information being presented along with an assurance

that it is being displayed at the proper scale. Given confidence in these two dependencies, GIS is

an indispensable tool in the field of wildlife management.

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TABLE OF CONTENTS Abstract…………………………………………………………………………………………… 2 Introduction……………………………………………………………………………………….. 4 1 Background Information on Wildlife Management………………………………………………. 5 Discussion of How GIS is Used in Wildlife Management………………………………………...7 Summary…………………………………………………………………………………………..17 References…………………………………………………………………………………………22

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INTRODUCTION

Like its sibling discipline conservation biology, the field of wildlife management blends

both pure ecology and more practical, spatially focused components of species and habitat

conservation (Goodfellow, 2014). As such, the use of geographic information systems (GIS) is

integral to the field through the myriad geospatial data and related analysis tools that they

provide. Goodfellow (2014) perhaps put it best when he stated that “the distribution of plant and

animal species across the globe recognizes no national or political boundaries, so the need for

detailed mapping and analysis of geographic features, species distribution and natural resources

was a primary need of this new discipline from its inception.” This is especially true today, as

floral and faunal species across the globe are facing extensive habitat and biodiversity losses in

the face of such threats as global climate change and increased urbanization of previously

undeveloped lands.

GIS technology provides an essential tool for addressing the complexities inherent in

natural and social systems, where uncertainty can often reign supreme (Artelle et al., 2013). The

technology can play a vital role in addressing one of the most common challenges in wildlife

management: answering the questions of when, where, and why species move (Artelle et al.,

2013). By incorporating species movements into a GIS, wildlife managers can gain a deeper

understanding of what drives the movements of targeted species, enabling them to implement

more efficient, site- and species-specific strategies and actions.

The use of GIS also assists wildlife managers in another basic, yet vital, way. Prior to

1950, all maps detailing the distribution of vegetation were drawn by hand (O’Neil et al., 2016).

These maps were then used to delineate habitat ranges for wildlife. The advent of aerial

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photography and satellite technology in the 1970s and the widespread adoption of personal

computers in the 1980s led to a revolution in mapping and habitat analysis, enabling wildlife

managers to more accurately analyze habitat across larger spatial extents (O’Neil et al., 2016).

Vegetation maps were then converted to digital files and habitat analyses became highly

automated, and the analytical tools and processes afforded by GIS quickly became heavily relied

upon (O’Neil et al., 2016). Today, as O’Neil et al. (2016) note, “GIS is an indispensable tool for

analyzing historical, current, and potential future habitat conditions for wildlife and for assessing

the spatial relationships among landscape features”.

BACKGROUND INFORMATION ON WILDLIFE MANAGEMENT

While there are seemingly limitless definitions one can use to describe wildlife

management, three common ideas are found in nearly every one. These are: 1) efforts that are

directed toward wild animal populations; 2) the relationship of those wild animal populations

and their terrestrial and aquatic habitats; and 3) anthropogenic manipulations or alterations of

those habitats or populations in order to accomplish a specified human goal (Yarrow, 2009).

Initially viewed as a way to ensure adequate fish and game supply for recreational uses, the field

of wildlife management has shifted over time to focus on applied ecology that is mutually

beneficial to both habitat and human and wildlife populations (Yarrow, 2009). While

governmental or academic institutions are the primary employers of practitioners in the field, any

individual who is actively working to alter the habitats of resident animal populations to achieve

a multispecies benefit can be considered a wildlife manager.

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Wildlife management strategies can either be passive (e.g., minimizing external

influences and letting natural processes take place) or active (e.g., controlled game hunts aimed

at decreasing predator populations of a specific prey species). The specific approach chosen

depends upon the desired outcome and the wildlife species in question. As the variety of wildlife

species includes game and nongame species, threatened and endangered species, and nuisance or

non-native invasive species, these approaches can be myriad. This results in a delicate balance,

as a successful wildlife management plan must abide by the following six rules as outlined by

MT FWS (2016):

• all management plans be based on solid, accurate information;

• the management of humans and their impacts on wildlife habitat be included in the

plan;

• plans must provide a multi-species benefit, including to both flora and fauna;

• wildlife numbers be kept at a level high enough to ensure that the carrying capacity

can continue to be met, yet low enough to avoid nuisance or negative impacts to other

species, including humans;

• habitat needs for wildlife species and humans be balanced; and

• conservation of resources must be balanced with preservation of resources.

The importance of the field of wildlife management goes beyond the protection of

wildlife species and their associated habitats. Most wildlife species, through their sensitivity to

changes in their surroundings, act as ecological indicators for human populations (MT FWP,

2016). Essentially, if animals are found to be disappearing due to pollution, drought, or another

environmental factor, it is likely that if left unchecked that environmental factor will also lead to

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negative impacts to nearby human settlements. Thus, the ability to accurately map a species’

habitat needs and movements is of paramount importance to the field.

DISCUSSION OF HOW GIS IS USED IN WILDLIFE MANAGEMENT

As noted previously, GIS is used extensively in the field of wildlife management. It

provides a solution to one of the most common challenges in species conservation and

management: how to record data on species movements and translate that information into

concrete management objectives (Allen and Singh, 2016). A greater understanding of movement

ecology, such as that which GIS provides, can provide the basis for more spatially and

temporally flexible management strategies whose efficacy is improved (Allen and Singh, 2016).

Further, GIS allows wildlife managers easy access to a wide variety of habitat related factors,

such as soil type, vegetation, and water availability, all of which assist in the modeling of

wildlife species movements and needs. The following examples and case studies highlight the

variety of ways that GIS is used in the field, including the methods used; the stated purposes and

objectives for each application; and whether or not the desired outcomes were achieved.

How GIS is Being Used to Model Wildlife Corridors

As Goodfellow (2014) noted, “wildlife does not recognize the boundaries created by

human activity”. Thus, the creation of one such boundary, highways, has led to increased habitat

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fragmentation of many wildlife species. These highways are responsible for a significant number

of deaths of large, roaming animals (such as black bears) that must traverse these obstacles in

order pass through the extent of their ranges (Goodfellow, 2014). In an attempt to provide safe

passage to affected species, wildlife managers design and install wildlife corridors (often in the

form of highway overpasses or underpasses) that are either continuous or provide stepping-

stones from one patch of habitat to another. The design of these corridors is intended to keep

migratory species and human populations from coming into (often negative) contact with one

another, reducing both mortality of wildlife and human species and construction costs associated

with highway design projects.

In order to locate the best possible position for a wildlife corridor, wildlife managers

often utilize GIS when researching the ranging and migration patterns of focal species before

suggesting any placements (see Figure 1). An example of one such study comes courtesy of

Clevenger et al. (2002) who worked to find the best placement for black bear wildlife corridors

in the areas of Banff National Park in Alberta, Canada, where the Trans-Canada Highway passes

through. Suitability maps detailing which areas were preferred by black bears for habitat were

developed using GIS software, and several sources of data on bear movements were compiled

and used to create and compare predictive models (Goodfellow, 2014). These models were then

used to predict the most likely linkage points to be used by bears, minimizing both construction

costs and black bear mortality resulting from traffic collisions (Goodfellow, 2014).

ESRI (2010) provides another example of how GIS can be used to design wildlife

corridors. The CorridorDesigner suite of tools, designed for ArcGIS by Professors Paul Beier

and Dan Majka at Northern Arizona University, provide wildlife managers “a user-friendly,

three-step process that applies least cost modeling for multiple focal species” (ESRI, 2010). The

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Figure 1: Maps detailing the calculated cost-distance habitat linkages for black bear (a), bobcat (b), and fisher (c) in the eastern Adirondacks. These maps were then merged to create the functional habitat linkage (d). Source: Graves and Wang, 2012.

core input of CorridorDesigner is habitat suitability modeling, which relate suitability to raster-

based layers such as land use/cover, elevation, topography, and human disturbance (ESRI, 2010).

This data is combined with a habitat suitability threshold to model a single species corridor, a

process easily replicated for any additional species under consideration (ESRI, 2010). These

single species models can then be joined to show a preliminary linkage design to use as a “best

choice” baseline for the wildlife corridor. Another set of tools within the suite can then be used

to evaluate all of the modeled corridors and compare them to more realistic alternatives, using

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such calculations as patch-to-patch distances and bottleneck analysis (ESRI, 2010). Ultimately,

CorridorDesigner provides data that can be used by wildlife managers and urban planners to

make educated decisions about the placement of wildlife corridors within the restrictions placed

upon them by the real world.

A final example of the use of GIS in creating wildlife corridors comes from Walker and

Craighead (2001), who analyzed the movement patterns of three of the umbrella species in the

Northern Rockies—grizzly bear, elk, and cougar—among the three large core protected areas

found within. Using GIS, habitat suitability models for each of the species were created which

were then combined with road density information to create regional (kilometer) scale cost

surfaces of species movement (Walker and Craighead, 2001). These models included the

following assumptions: that good corridors are comprised primarily of preferred habitat types;

that humans pose problems for successful transit; that current human developments are

permanent; and the least-cost path provided the greatest probability of survival for an animal

when traversing the entire distance of its range (Walker and Craighead, 2001). The model also

included three GIS inputs essential to determining the best potential corridor routes: 1) habitat

quality; 2) length of forest and shrub/grassland interface; and 3) road density (Walker and

Craighead, 2001). The initial approximations of the models allowed the researchers to identify

probable movement routes for each of the three species, as well as critical barriers, bottlenecks,

and filters where projected corridor routes intersected with high risk habitat (Walker and

Craighead, 2001). These results were then shared with local land management agencies so that

the results could be incorporated into current and future planning activities in the region.

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How GIS is Being Used to Preserve Biodiversity and

Protect Endangered Species and their Habitats

Referred to as “the application of choice” by wildlife managers focused on conservation

biology, GIS plays a pivotal role in measuring and monitoring biodiversity; analyzing the spatial

distribution of threatened and endangered species; and identifying and monitoring patterns and

priorities to be incorporated into management plans (Krigas et al., 2012; Goodfellow, 2012). Any

assessment of biodiversity must necessarily include a wide variety of spatial and attribute data,

something GIS technology excels at accommodating high volumes of (Salem, 2003). In a GIS,

these data can be united as geodatabases comprised of multiple polygon and raster layers

depicting the attributes of various collection sites for target species. Such attributes include

“precipitation, land cover, terrain, topography, soil typography, temperature, and climate”

(Goodfellow, 2014). After analysis, the GIS can then be used to produce summarized fact sheets

reflecting the ecological preferences of a target species such as the one depicted in Figure 2

(Goodfellow, 2014).

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Figure 2: Example of a target species fact sheet prepared with the use of GIS. Source: Krigas et al., 2014.

Wildlife managers focused on biodiversity often employ a technique pioneered by the

U.S. Geological Survey (USGS) known as gap analysis, which focuses on the conservation status

of common floral and faunal species. Gap analyses are not only an important tool for wildlife

managers and conservation biologists but are also used by decision makers, planners, private

interests, and others to assess biodiversity and habitat loss; monitor the affects of climate change;

inform the siting of renewable energy projects; and assist in the management of protected areas

(USGS, 2012). The genesis for this analytic approach came from a desire to visually analyze the

interconnectedness of three spatial components—land cover, predicted distributions of vertebrate

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species, and the location and conservation status of predicted areas (USGS, 2015). Each of these

three components are entered into a GIS as individual data layers (see Figure 3) which are then

analyzed to “determine how much of a vertebrate species’ or a land cover’s distribution occurs in

areas managed for the long-term maintenance of biodiversity” (USGS, 2015). The determination

is made through the overlaying of the maps depicting the location of plant and animal habitats

with the additional maps showing where the protected areas are; if predicted floral and faunal

species are found to not be in the same location as a protected area, then they are considered not

to be protected (USGS, 2015). Armed with this information, wildlife managers can then advocate

for protections on behalf of such species and their habitats. As USGS (2015) note, products from

a typical gap analysis include “digital land cover maps; digital animal distribution maps; digital

protected areas maps; identifications of ‘conservation gaps’; identifications of species-rich areas;

downloadable datasets in multiple formats; and assessments of the conservation status of

vertebrate species in the United States”.

Figure 3: The steps involved in a typical gap analysis. Source: USGS, 2015.

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USGS manages a repository for gap analysis datasets that is available to the general

public under the National Gap Analysis Program (GAP). When developing GAP, USGS had the

realization that many protected areas (such as National Parks and National Wilderness Areas)

often get set aside without a detailed understanding of their value to floral and faunal species

conservation (USGS, 2012). This results in a misallocation of protection, as “many protected

areas have little significance in terms of biodiversity, while many biodiversity-rich areas lack

protection” (USGS, 2012). By using GAP, wildlife managers can better match their biodiversity

goals to land protection programs and activities, resulting in the highest rate of biodiversity

preservation achievable (USGS, 2012; Goodfellow, 2014). GAP has been used by the states of

Nevada and Wyoming in developing their revised State Wildlife Action Plans; to model the

distribution of endangered arboreal species in Egypt; in ex situ conservation strategies aimed at

halting biodiversity loss of plant species; and by The Nature Conservancy to develop specific

biodiversity preservation and conservation plans across the globe (Salem, 2003; Krigas et al.,

2012; USGS, 2012).

A Review of how GIS in Used by the U.S. Fish and Wildlife Service

Charged with creating and implementing wildlife management plans and policies across

the country, the U.S. Fish and Wildlife Service (USFWS) relies heavily upon GIS. USFWS

views the geospatial data and services provided by technologies such as GIS as being critical

elements of their work, playing a vital role in all of their long-term plans (USFWS, 2014). The

technology is especially prevalent in four of their core program areas: Endangered Species and

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Fisheries and Habitat Conservation; Migratory Bird Conservation; the National Wildlife Refuge

System; and the Landscape Conservation Cooperatives. Along with global positioning systems

(GPS) and remote sensing, GIS is primarily used by USFWS in these program areas to visualize,

monitor, and research wildlife habitat and migration patterns. Managers and policymakers then

used this information to make such detailed decisions as whether or not species are to be listed

under the Endangered Species Act and how floral and faunal communities are responding to

toxic spills. The technology is also especially useful in supporting the diverse operational

activities of the National Wildlife Refuge System. These include asset management, law

enforcement, water resources, and fire management, along with uses in analyzing opportunities

for strategic land acquisition and realty transactions (USFWS, 2011).

USFWS also houses and supports many GIS applications whose data are made available

to the general public. These applications include the National Wetland Inventory, which details

the extent and status of the nation’s wetlands; the National Wild Fish Health Survey Database;

the Critical Habitat Portal, which provides the public detailed information on Threatened and

Endangered Species and their designated Critical Habitats across the country; and the Waterfowl

Production Area, a useful tool for Midwestern hunters that details areas of waterfowl production

in the region (USFWS, 2012). These applications assist USFWS in reaching the widest possible

audience for their georeferenced data (USFWS, 2012).

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How GIS is Used in Managing and Monitoring Wildlife in Minnesota

Similar to USFWS, the many state resource management agencies located across the

nation also rely heavily upon GIS. For example, the state of Minnesota and their Department of

Natural Resources (MN DNR) have an array of projects utilizing GIS technology in order to

effectively monitor and manage wildlife within the state. These include habitat assessment and

management; population surveys and monitoring; and facilities management (MN DNR, 2006).

The state is also home to 1,380 Wildlife Management Areas (WMAs) that cover 1.2

million acres. Begun in 1951, the goal of the WMAs has been to acquire, develop, and maintain

land that can support the multipurpose uses of wildlife habitat, public hunting, and wildlife

observation (MN DNR, 2006). A GIS was created to assist in managing this extensive system.

Boundaries were first delineated according to various descriptive information and management

goals, then entered into the system and created as a polygonal layer in the GIS. Vegetation

through the WMAs was then mapped in a manner consistent with the National Vegetation

Classification System; that is, a five level hierarchy was used that allowed for flexible specificity

amongst vegetative types (MN DNR, 2006). Finally, management and user data were entered

into the GIS representing gates, water control and nesting structures, camping areas, and roads

and trails (MN DNR, 2006). Upon completion, the WMAGIS Application was made available to

the general public. This application allows users to search for and view each of the individual

WMAs and plan trips according to their intended recreational goals (such as finding a handicap

accessible WMA where one can view deer, pheasants, and waterfowl, for example).

Additionally, it allows researchers the ability to view and monitor the variety of vegetation found

in each WMA.

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GIS is also used by MN DNR to monitor the encroachment of urbanized and agricultural

areas on the WMAs and to conduct aerial surveys. The approach of the former incorporates

census data into the above system where urban and agricultural density analyses are completed.

Regarding the aerial surveys, MN DNR captures real-time GPS waypoints and tracks directly

into a GIS, a marked improvement upon their previous technique of using a compass and paper

maps (MN DNR, 2006). MN DNR has also used GIS (specifically ArcGIS) to create a wildlife

habitat relationship model that can predict habitat distribution and land cover within a specified

range extent (MN DNR, 2006).

SUMMARY

As a technology that excels at accommodating large amounts and varieties of spatial and

attribute data, GIS is an essential tool for any wildlife management practitioner. Wildlife

managers are by their very profession focused on analyzing the current and predicted spatial

distribution of target species and the spatial relationships between those species and the

landscape features of their habitats. Information embedded in a GIS such as soil type, vegetative

cover, precipitation amounts, and temperature provide managers the ability to easily identify

gaps in spatial coverage between target species (whose distribution and habitat needs are also

included in the GIS) and proposed protection or land use plans. The most effective data for this

purpose cover large temporal extents that allow for monitoring of the exact location and extent of

change within an ecological system (Salem, 2003). As such, a GIS can be used to model

wildlife-habitat relationships and populations of target species; to conserve wildlife

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communities; and to assess risks facing target species from current and projected land use change

and anthropogenic encroachment (O’Neil et al., 2012). For further reading on how GIS is used in

each of these examples the reader is referred to the work of O’Neil et al. (2012).

This paper provided a review of how GIS is used in the field of wildlife management

through an examination of four specific approaches. First, it was discussed how wildlife

managers use GIS in the design and installation of wildlife corridors. These wildlife corridors

(which often take the form of highway overpasses or underpasses) are either continuous or

provide stepping-stones from one patch of habitat to another. They are aimed at keeping

migratory and roaming species and human populations from coming into contact with one

another, reducing wildlife mortality and highway construction costs. Examples were given of

GIS being used to optimize placement of wildlife corridors for black bears in Banff National

Park in Alberta, Canada, and for three of the umbrella species in the Northern Rockies—grizzly

bear, elk, and cougar. In each instance, habitat suitability models for the individual species were

compiled detailing species movements along with habitat needs and preferences. These models

then incorporated road density information to predict the most likely used habitat linkage points

and where potential “hotspots” existed. Further, Walker and Craighead (2001) created kilometer

scale cost surfaces of species movement that were then shared with local land management

agencies for implementation in their current and future planning activities in the region. The

CorridorDesigner suite of tools designed by Beier and Majka for ArcGIS was also discussed; this

suite of tools provides a user-friendly, three-step process similar to the ones just described. Using

the software, easily replicated single species corridors to be used as baselines are modeled. These

are then compared with more realistic alternatives that take into account all of the restrictions

placed upon managers and planners in the real world.

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Next, the concept of using GIS to preserve biodiversity and protect endangered species

and their habitats was discussed. The primary application of GIS in these studies was in the form

of gap analysis, an overlaying technique pioneered by the USGS. These analyses focus on the

conservation status of common floral and faunal species by visualizing the interconnectedness of

three spatial components—land cover, predicted distributions of vertebrate species, and the

location and conservation status of predicted areas (USGS, 2015). Each of these three

components are entered into a GIS as individual data layers which are then overlaid on top of

one another. This approach yields a view of which plant and animal habitats are located in which

protected areas and more importantly, which ones are not. Armed with this information, wildlife

managers can tailor their plans accordingly and advocate on behalf of such species and their

habitats. GAP, the National Gap Analysis Program managed by the USGS, was also discussed.

GAP is a repository for gap analysis datasets that is available to the general public. During its

development, USGS realized that many areas were being given protection without regard for

their level of biodiversity, resulting in a misallocation of protection. By using GAP, wildlife

managers can better match their biodiversity goals to land protection programs and activities,

resulting in the highest rate of biodiversity preservation achievable (USGS, 2012; Goodfellow,

2014).

A review of the use of GIS by USFWS followed. USFWS relies heavily upon the

geospatial data and services provided by technologies such as GIS and views them as critical

elements of their work (USFWS, 2014). The use of GIS is especially prevalent in four of their

core program areas: Endangered Species and Fisheries and Habitat Conservation; Migratory Bird

Conservation; the National Wildlife Refuge System; and the Landscape Conservation

Cooperatives. It is primarily used in these program areas to visualize, monitor, and research

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wildlife habitat and migration patterns, and has been used to make such detailed decisions as

whether or not species are to be listed under the Endangered Species Act and how floral and

faunal communities are responding to toxic spills. Further, USFWS houses and supports many

GIS applications whose data are made available to the general public. These applications, such as

the National Wetlands Inventory, provide the public with detailed information that can be used

for research or recreational purposes and assist USFWS in reaching the widest possible audience

for their georeferenced data (USFWS, 2012).

Finally, it was discussed how GIS is used in managing and monitoring wildlife in

Minnesota. MN DNR employs a variety of GIS applications including habitat assessment and

management; population surveys and monitoring; and facilities management (MN DNR, 2006).

A GIS was also created to manage the state’s 1,380 Wildlife Management Areas (WMAs), which

are used to support the multipurpose uses of wildlife habitat, public hunting, and wildlife

observation (MN DNR, 2006). WMA boundaries were delineated and input into the GIS as a

polygonal layer with WMA vegetation then added as a five level hierarchy allowing for flexible

specificity amongst vegetative types (MN DNR, 2006). After adding management and user data

such as water control structures and camping areas, the WMAGIS application was made

available to general public for use in researching academic or recreational goals. Encroachment

of urbanized and agricultural areas on the WMAs is also tracked using GIS by incorporating

census data into WMAGIS. Additionally, the state uses GIS to conduct aerial surveys, capturing

real-time GPS waypoints and tracking them directly into a GIS.

While this paper has found GIS to be an essential component of any wildlife management

plan, it must be noted that the efficacy of a GIS is highly dependent upon the quantity and

quality of its data. Kirgas et al. (2012) found that lack of data is the most commonly encountered

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obstacle to the use of GIS in conservation planning. Thus, it is imperative that any GIS user in

the field of wildlife management be confident that their dataset is of sufficient size and detail.

Additionally, O’Neil et al. (2012) cautioned GIS users to be sure that they understand the

information being presented. That is, when depicting information about a target species, the scale

or level of information needed to study the problem of interest must be fully understood and

taken into account (O’Neil et al., 2012). Displaying the right question at the wrong scale (such as

displaying habitat suitability, which requires fine scale information, at a coarse scale) misleads

map viewers and presents potential false-positive outcomes. Provided that there is confidence in

the amount and accuracy of data and how it is being displayed, GIS is an indispensable tool in

the field of wildlife management.

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