1. Redesigning the Captive Polar Bear (Ursus maritimus)
Exhibit to Prevent Stereotypical Behavior and Promote
Positive Visitor Experience
Cindy Hoang
Applied Animal Behavior in Captive Populations
NSCI 579 – 001
December 4, 2012
Semester Project Proposal

2. Hoang 2
Table of Contents
Terminology, Guidelines, and Regulations…………………………………….
3
Project Overview……………………………………………………………….
4
Stereotypical Behavior………………………………………………………….
5
Enrichment……………………………………………………………………...
6
AZA Recommendations and Requirements……………………………………
9
Creating an Enrichment Plan…………………………………………………...
10
Ethogram Summary…………………………………………………………….
11
Polar bear Exhibit Redesign Layout…………………………………………...
15
Conclusion………………………………………………………………………
16
References………………………………………………………………………
17

3. Hoang 3
Terminology, Guidelines, and Regulations
Conservation: careful preservation and protection of something (merriam-webster, 2012).
Endangered: threatened with extinction (merriam-webster, 2012).
Enrichment: animal husbandry principle which is used to improve the quality of captive care by
providing sensory stimulation via environmental, feeding, visual, olfactory, auditory, etc.
(Sherperdson, 1998; Wells, 2009; Swaisgood and Shepherson, 2005; Fischbacher and Schmid,
1999; Newberry, 1995).
Enclosure/Habitat: area in view of the public, which the animal is enclosed (AZA, 2009).
Housing Den: area out of public viewing, where the animals will be housed, fed, and veterinary
care, etc. (AZA, 2009).
Maternity Den: used only by the females during maternal care.
Off-Exhibit Area: any area within the exhibit, which the public is not permitted access.
Stereotypical Behavior: repetitive behavior induced by frustration, repeated attempts to cope, or
possible brain dysfunction (Mason et al., 2007).
Guidelines and Regulations:
Association of Zoos and Aquariums (AZA, 2009)
USDA Animal Welfare Act and Animal Welfare Regulations (AWR, 2005)
Marine Mammal Protection Act (MMPA, 2007)
Manitoba Polar bear Protection Act (PBPA, 2002)
Endangered Species Act (ESA, 1973)

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Project Overview
Project Site The Denver Zoo – Denver, CO
Site Description The organization wants to secure a better world for animals through human
understanding. They want to transform into a conservation center for all
animals. They envision a world where people can appreciate, respect, and
conserve animals and their habitats. All animals, big and small, from all
over the world are valued and careful management of the environment is
very important.
Identified
Problems and
Potential Changes
During my visit to The Denver Zoo, the Director of Public Programs
identified the stereotypical behavior of pacing in the Polar bear and
suggested a potential solution of enclosure rotations. Envisioning the future
of the Polar bear enclosure, the Director imagined a more
interactive/personal experience for the visitors and decreasing the pacing
behavior. In addition, the awareness of conservation and education of the
species need to be implemented.
Project Description
and Objectives
The Polar bear exhibit redesign will be presented using the AZA guidelines
and published peer-reviewed articles. In order to create the new layout of
the exhibit, an ethogram was made at the present-day enclosure. The new
design is necessary to increase the welfare of the subject and promote
positive visitor experience; this will be addressed by:
 Preventing the stereotypical behavior of pacing by increasing the usage
of enrichment
 Providing a more stimulating and appealing enclosure for both the
animal and the visitors
 Providing an educational experience to visitors without stressing the
animal

5. Hoang 5
Stereotypical Behavior
Stereotypical behaviors, commonly observed in captive animals, is a concern for many
groups and organizations interested in animal welfare including individuals with personal
awareness of the issue. The observation of stereotypical behavior may be used to identify the
well-being of the animal; in the presence of the repetitive behavior, it raises awareness of
potential frustration and lack of sensory stimulation (Swaisgood and Shepherdson, 2005). The
most studied species to contribute to stereotypy research are felids followed by the ursids and
hominids (Swaisgood and Shepherdson, 2005). The three families are one of the top zoo animals
that display the behavior (Swaisgood and Shepherdson, 2005). It is important to be aware of the
different forms of stereotypy such as pacing, oral, regurgitation, and repetitive movement
(Swaisgood and Shepherdson, 2005). Out of the stereotypical behaviors, pacing, which is defined
as “more than three traverses of a definite path, such as the back wall of the exhibit or the edge
of the pool,” was found to be the most common (Swaisgood and Shepherdson, 2005).
In a comparison of 28 zoological parks with brown bears (Ursus arctos), a close relative
to the polar bear, brown bears displayed stereotypical behaviors of pacing, circling or walking in
a figure eight, head-tossing, and swaying (Montaudouin and Le Pape, 2005). The stereotypical
behavior was performed more frequently in adults than the younger individuals; adults paced,
while the young bears head-tossed. In addition to comparing the individuals, Montaudouin and
Le Pape (2005) also compared the surrounding factors such as the characteristics of the
enclosures, housing management, and social relationships. Taking all of the external factors into
consideration, it was found that:
 Circling behavior was significantly lower when the area surrounding the
enclosure/exhibit was visible by the bears.
 Lower levels of stereotypy was found when there was either a medium or large pool (one
or more bears can move but cannot swim OR bears can swim)
 Higher levels of stereotypy were found in bears that were locked inside during the night
for feeding which resulted in the behavior during the afternoon.
 Those fed in the morning or afternoon showed significantly lower levels than those fed at
night.
After looking over the comparison performed by Montadouin and Le Pape (2005), it is
recommended that changing the housing and management strategies can reduce the stereotypical
behavior.
 A surrounding view is more favorable.
 A large or medium pool is recommended.
 Allow the bears to have free access to the indoor enclosure during the day and not lock
them up at night.
 In addition to changing the feeding time to mornings, by scattering small pieces of food
around the enclosure will promote more curiosity and foraging.

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Enrichment
Another approach in addressing stereotypical behavior is providing enrichment; this
method is practiced more frequently in the zoo community today. Enrichment is a husbandry
activity used to provide sensory and mental stimulation that can prevent and reduce the
occurrence of stereotypical behaviors (Swaisgood and Sherpardson, 2005). Mellen and Sevenich
Machphee (2001) believe the goals of enrichment should be to:
1. Enrich the captive environment that will enhance the psychological and physiological
well-being of animals under care; therefore, enrichment enhances animal welfare.
2. Identify and reduce the potential sources of chronic stress and/or enhance an animal’s
ability to cope successfully with acute stress.
3. Reduce and eliminate the abnormal behaviors and provide opportunities for appropriate
behaviors and activity patterns.
Enrichment can be provided for the animal in different ways and can fall into two categories:
feeding and non-feeding (Swaisgood and Shepherdson, 2005).
FEEDING NON-FEEDING
 Increase the foraging/search time by scatter
or hiding food
 Increase the capture time by implementing
live prey
 Increase extraction time such as a puzzle
feeder
 Change the variability of feeding times to
prevent predictability
 Increase the number of feeding/day
 Adding non-permanent novel objects, such
as inedible objects for manipulation/play
 Adding scents/scented materials or
auditory
 Husbandry behavior performed during
training to challenge cognitive skills
 Rotating enclosures between two or more
enclosures
 Constructing a new enclosure – habitat
redesign
 Physical structure of the environment
Within the two categories, there are subdivisions that need to be discussed in further detail. In
order to provide relevant enrichment for the subject species (Polar bear), it is necessary to
compare the effectiveness of the different types of enrichment.
FEEDING
Using multiple feedings, hiding food, using devices that can be manipulated (puzzle
feeders), or offering food at different times has been found to stimulate the bears and decrease
stereotypical behavior (Fischbacher and Schmid, 1999). When comparing the different types of
feeding enrichment, 70 – 80% of low value foods were scattered in the enclosures in the
morning, and the rest of the food was given in the housing dens at night (Fischbacher and
Schmid, 1999). They compared various feeding devices such as:
 Food holes – concrete tubes in the ground where food was hidden
 Branch racks – metal construction where fresh-cut branches can be fixed
 Narrow holes – filed with raisins at one end and fixed to the ground at the other end

7.  Honey trees – a dead climbing tree with a cup-like hollow at a 3.5 m height where syrup
Hoang 7
can be pumped
Fischbacher and Schmid (1999) found that the feeding enrichment significantly increased the
foraging behavior but only during the initial release in the mornings and stopped before noon or
early afternoon. This may be because the food was only scattered in the mornings prior to the
release and not throughout the day. It can be concluded, although food enrichment decreases
stereotypy, it has no long-term or delayed effect on the behaviors during the day (Fischbacher
and Schmid, 1999). An issue using food-related objects for environmental enrichment is that the
effects last only as long as the food lasts (Altman 1999). In captivity, food is predictable and
always available, resulting in decreased search time and handling (Newberry, 1995). Some other
methods that may reduce food-related stereotypes include smaller, more frequent meals,
scattering food in unpredictable locations, increasing skill and time to get food (maybe providing
live prey), and potentially increase the fiber to increase the feeling of fullness (Newberry, 1995).
EFFECTS OF INEDIBLE, MANNIPULABLE OBJECTS
The short amount of time the bears spent engaging in food enriching behaviors motivated
the approach in using inedible objects to decrease stereotypical behavior. Altman (1999)
compared the usage of inedible objects in captive bears. The polar bears in the study were given
two large (61 cm long x 122 cm diameter), hollow, industrial strength white plastic drums with
handles (Bonar Plastic AquaCulture Floats). One of the drums was airtight and could float, while
the other had small holes allowing the other drum to fill with water. Altman (1999) found the use
of the inedible objects decreased pacing, excessive inactivity, or both. The interaction of the
polar bears with the objects are listed below:
 Climbed out of the pool and jumped on the floating drum
 Flipping the drum into the air with their paws
 Floating on their backs with their paws wrapped around the drum
 Pushing the drum ahead of them with their snouts or pulling with their teeth
 Pulling the drum underwater to let it fill with water and pushing it back up to the surface
Altman (1999) did not observe a decline of interaction and habituation after a month. Additional
ideas for enrichment “toys” include (AZA, 2009; Canino and Powell, 2010):
 Plastic floats
 55 Gallon barrels
 Boomer balls
 Plastic weeble
 Cut up rubber and canvas hose
 Traffic Cones
 Heavy duty plastic outdoor play such
as sleds, picnic tables, climbing
structures
 Beer kegs and plastic water cooler
jugs
PHYSICAL STRUCTURE OF THE ENVIRONMENT
Aside from inedible objects, the physical structure of the environment can affect the
animal’s behavior. It is recommended to add complexity to the environment by adding some
elevation or levels to allow different functional areas (Newberry, 1995). Having access to
different areas of the enclosures such as their indoor and outdoor living space may enhance more

8. exploration (Newberry, 1995). Providing the animal with covered shelter, ledges, and climbing
structures can give the animal more security and awareness of its surroundings (Newberry,
1995).
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SENSORY STIMULATION – SMELL AND AUDITORY
Wells (2009) discussed the potential effects sensory stimulation can have on captive
animals and the benefits. In recent studies, triggering one or more of the animal’s senses has
been used as environmental enrichment (Wells, 2009). Studies performed in humans and
auditory stimulation is well known and reported. Keeping auditory stimulation into
consideration, Wells (2009) applies it to animals in captivity. Auditory stimulation can be
classical or country music, playing prey sounds, or sounds of the rainforest. Visitor perception of
what sounds should be played has influenced the enrichment. Studies found lowland gorillas
preferred classical music, whereas the visitors preferred sounds of the rainforest (Wells, 2009).
Another study found predatory species responded with higher levels of activity when they heard
prey sounds from a moving object that would release treats, which contributed to appropriate
species behavior (Wells, 2009). For some species, adding auditory stimulation to cover a noisy
environment, may actually do worse since the animals have no option in removing the sound
(Newberry, 1995).
On a similar note, the olfactory stimulation or the smelling sensation can have positive
and negative impacts. Negative olfactory stimulation come from the use of disinfectants,
cleaning supplies, too much animal waste, and predator smells. Elimination from species is used
as an informational tool for social status, and although regular cleaning is necessary, it is
recommended to clean half of an animal’s enclosure at a time (Wells, 2009). Positive stimulation
can come from essential oils, plant odors, pheromones, and prey scents. The safety and toxicity
of essential oils and plants have to be considered before placing them into a habitat (Wells,
2009). For some species of animals, visual stimulation may play an important role in enrichment.
WHEN ENRICHMENT BECOMES HAZARDOUS
Although enrichment plans are meant to improve the well-being of the animal, there have
been cases where the items have been unsafe. It is highly important to consider the enrichment
safety issues and potential hazards (Hare et al., 2008). Consideration of the presentation of
enrichment is important (Hare et al., 2008):
 Body part entrapment due to too small or too large of holes or hanging materials
 The materials of the enrichment
 Overnight and unsupervised enrichment
 Items can get stuck in the animal’s teeth or mouth and prevent feeding
 Ingestion of non-food items can cause health concerns such as irritation and blockage
 Disease-causing, toxic, and irritating materials and food items – ex. Salmon poisoning in
the polar bears

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AZA Recommendations and Requirements
In order to ensure the highest quality care and improvement of well-being for the polar
bears, the Polar bear Care Manual from the Association of Zoos and Aquarium (2009) will also
be referenced. In order to ensure well-being of the polar bear, the AZA (2009) recommends:
Temperature  Hills, trees, shrubs, branches, rocks, and stumps provide shade
throughout the day
 Free-access to air conditioned spaces, chilled water, or ice piles
 Sprinklers, misters, and wind generating fans
 Heat stress is greater risk than the cold
Habitat  Resting platforms, water features, and nesting sites
 Naturalistic landscape and functional
 Open/panoramic views, and pits with materials
 Soft substrate instead of hard
 Easily modified if necessary
Furniture  Moveable boulders, trees, logs
 Climbing structures and platforms to observe distances
Nesting Materials  1350 ft2 soil, straw, woodchips, or other soft substrates for
coverage
Space  5400 ft2 dry land and additional 1650 ft2 per additional bear
 Pool must be at least ~5-9 ft deep and 96-760 ft2 surface area
 Pools must be irregularly shaped with shallow and deep ends
 Pools suggested to have cool saltwater with live fish, smooth walls
and ledges, an island, polar themed floats, waterfalls or streams,
changing currents, and wave machine
 Freshwater streams in addition to the pool
Off-exhibit housing  Each bear must have its own area for sleeping have shift facilities
 Must be at least 807 ft2 and additional 269 ft2 for each additional
bear.
Maternity Dens  Quiet area away from the exhibit
 At least 2.5 m x 2.5 m x 2.5 m
 Not allowed access to males
Barriers  Barrier walls must be at least 5 m high/deep
 Glass barriers must be at least 2 inches thick
 Have elevated areas to avoid the pit-like effect and bears should be
allowed to see beyond their enclosures
 The public should be kept at least 6 m away vertically/horizontally
unless separated by a glass barrier (2 inches thick)

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Creating an Enrichment Plan
Because there are different ways enrichment may be provided, it is recommended to
create an enrichment plan for each animal/group; what may work for one animal may not work
for another (Mellen and Sevenich Macphee, 2001). Careful
consideration of the different types of enrichment and the
presentation will play a large role in the success of the habitat
redesign project.
Prior to introducing the enrichment, Mellen and
Sevenich Macphee (2001) have created a “framework,” which is
used to create a self-sustaining enrichment program. The
components of the framework include 1) goal setting 2)
planning 3) implementing 4) documenting 5) evaluation and 6)
re-adjusting (Mellen and Sevenich Macphee, 2001). It is
recommended to use this framework when creating an
enrichment plan:
1. Goal setting – what do we want this enrichment to
achieve?
2. Planning – given the potential enrichment ideas, how do
we decide which ones should be implemented? How do
we review/approve the enrichments? How will animal
care staff make sure the enrichment is routinely
provided?
3. Implementing – who will implement the enrichment?
4. Documentation – what happened? Did the enrichment
work? All the observations need to be recorded.
5. Evaluation – after a period of time, the outcome of the
enrichment must be analyzed. Did we like what
happened? Did the enrichment achieve the goals we set?
6. Re-adjusting – adjust the plan if necessary and start the
process over.
It is recommended that managers and keepers are to outline a
plan to promote the behaviors and activity patterns that address
the animal’s natural history within the organizations resources
(Mellen and Sevenich Macphee, 2001).
For the habitat redesign, an assessment of the current polar bear
enclosure at The Denver Zoo was performed.
Before an implementation of
a habitat redesign can take
place, it is important to
consider all factors relevant
to the design such as visitor
perception, zoo keeper
accessibility, feeding
schedules, management, the
types of enrichment, and
individual preference of the
animal. Although visitor
perception does not directly
play a role in the well-being
of the animal, it is important
to raise awareness and
educate the public of
endangered species for
organizations working
towards conservation.

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Ethogram Summary
Weather Conditions: Rain/Snow at 55°F – cold weather conditions with intermittent snow intervals,
not windy, potentially small sized hail
Species Studied:
 Polar bear (PB) (Ursus maritimus)
 Age and Sex Unknown
 Two bears were observed in two separate
enclosures
 Polar bear A (PBA) is in enclosure 1
 Polar bear B (PBB) is in enclosure 2
 Both of the subjects were exhibited
separately during time of observation
 Feeding times unknown
Enclosure 1: Outdoor
 There is a large pool which takes up what
appears to be 80-90% of the enclosure
 There is a walking strip with ~5 ft width
from the pool to the wall which wraps
around the pool
 At the right side of the pool is a waterfall
which is 8-10 ft tall which flows into the
pool
 At the far left side is a larger space that is
~10 ft from the pool to the wall
 The enclosure is covered by ~ 10-15 ft of
“rock” material around the enclosure and
in front of the enclosure is a viewing
glass which runs along the entire front of
the exhibit (the entire length of the
exhibit was not measured)

12. Enclosure 2: (Outdoor)
 In comparison to the first enclosure, this is ~2-
3x the size of the first one, by width and length
Hoang 12
(Image on the Left)
 In the enclosure is the “Polar bear
Playground,” which is featured as their
enrichment for the bears to encourage natural
behaviors.
 It is placed ~ 10 ft from the fencing
 The playground consists of fish tubes, rope,
floats and bouys, grooming brush, burrow,
digging/foraging area, and browse receptacles.
 Fish tubes: used to hold fish and other treats to encourage sense of smell
 Rope: allows keepers to add or remove objects
 Floats and Bouys: for pushing, pulling, and bouncing behaviors
 Grooming Brush: for bears to rub and scratch
 Burrow: to explore, escape, or take a nap
 Digging/foraging area: hole in the floor for bears to explore and find hidden treasures
 Browse Receptacles: used for scratching and chewing on
(Image on the Right)
 This is the midsection of the habitat which
consists of a large pool which is fairly deep
and can be viewed in a “cave” underneath the
exhibit.” This provides an “underwater”
experience for the visitors.
 Towards the back of the exhibit is a large
cave/den which the bear can lay under for
shelter
(Image on the Left)
 This is the far right of the habitat and shows
the rest of the pool
 The pool uses 70-80% of the space in the
habitat
 In the pool is a floatation platform which is
potentially used to replicate “sea ice”
 In the far right corner, seems to be an access
door either to the indoor facility or to the
neighboring enclosure

13. Hoang 13
Enclosure #1
Pros:
 It allowed the visitors to come close to the
PBA with a barrier
 PBA seem comfortable and very interested
in the visitors and stayed along the viewing
glass
Cons:
 Although there was a large pool, it took up
a lot of space in the enclosure. There was
also no provided cave/den area as the other
enclosure
 The appearance of the viewing glass in
enclosure #1, which covered the entire
enclosure, was not as appealing because it
did not feel as like an “open-concept” as
the other enclosure
 Gives a small appearance and a negative
impression on animal welfare and comfort
 Does not seem to have many areas for
foraging behavior
Enclosure #2
Pros:
 It had a very large open-concept, which
gave a visitor impression of positive animal
welfare
 Provided many areas and activities of
enrichment such as the playground, pool, a
flotation “sea ice,” and a cave/den area for
shelter and rest
 Has areas available for foraging
 Provides an “underwater” experience for
the visitors when the animal is in the pool.
This is a good source of education
Cons:
 The enrichment playground was too close
to the fence line, I think the polar bear
would feel uncomfortable to use it with
people nearby
Observation summary: Both PB were not interested in the pool or exploring the area during my
time of observation. This may be due to weather, lack of visitors (no human interaction), or they
may have previously been fed prior. Although I am aware of the adaptations of these animals in
inclement cold weathers, I am unsure if it is favorable for displays of active behavior. I
overheard a comment from a visitor when observing PBA in the enclosure #1 (with the viewing
glass). She stated, “Oh look, he’s laying down. I hope you’re happy in there.” I took this
response to the animal as a state of concern and worry.
In addition to observing their behaviors, I analyzed the structure of the enclosure. I
thought it was strange for both enclosures to differ in size and presentation. One enclosure seems
more pleasing to the visitors than the other. Personally for myself, I felt the enclosure with the
open concept was much more appealing than the enclosure that was surrounded by rock and a
viewing glass. Especially since PBA kept sniffing and positioning his head in an upward
behavior.

14. Personal Comments:
 Because I am not observing the whole day or even 3-4 hours, PBB may be using the
Hoang 14
playground, just not at the time of my observation.
 I think PBB will feel more comfortable with the playground if it wasn’t so close to the
fencing. It is the closest site of “enrichment” compared to the other areas.
 If there were a combination/compilation of the two enclosures, it would provide a better
experience for both the animals and the visitors.
 If the open-concept of the fencing in combination with a smaller viewing glass in one
enclosure, would provide a more positive experience. It would benefit for those who want to
get really close to the animals (if the animal chooses) and the animal would look more
natural and comfortable.

15. Hoang 15
Polar bear Exhibit Redesign Layout
Figure 1

16. Hoang 16
(Cont.)
The Polar bear Exhibit Re-design was created using the studies and comparisons
enrichment tools and the occurrence of stereotypical behaviors. Shown in Figure 1, the exhibit is
designed with an outdoor/indoor perspective for the visitors and with an open concept for the
polar bears. Surrounding each enclosure are either rail barriers or viewing windows. This allows
the polar bear to see the surroundings without being completely sheltered from its environment.
It is also recommended for the land to have a softer surface than the traditional “grotto” and
“rock-like” structure. The land should also be built on a slant/level instead of a flat surface, this
is recommended to prevent the “pit-like” effect in addition to a climbing structure that allows the
polar bear to view its surroundings at different levels. In addition, the enclosure should provide a
naturalist, yet functional living space.
In accordance with AZA (2009), the visitors should be at least 6m away either vertically
or horizontally, unless separated by a two-inch thick viewing window. Between the two
enclosures is an elevated indoor walking bridge which contains a viewing window for an aerial
view. Since the polar bear prefers a softer walking surface, placing a concrete or hard like
surface near the doors may prevent pacing near the doors. In addition, if the polar bear chooses,
the doors should be open for indoor/outdoor access.
The size of the pool is also important in the layout of the enclosure. Both pools have
various levels of shallow and deep water and should be large enough to swim in. In addition, one
enclosure has a waterfall and the other will have an island. A representative from The Denver
Zoo also liked the idea of having a “swimming experience with the polar bears,” which is also
incorporated into the layout. The indoor swimming for the visitors is a wading pool that is
directly next to the bear pool which is separated by a two inch thick viewing window. This may
also be a form of visual stimulation for some of the animals that like the human interactions.
When looking at Figure 1, the enclosure to the right consists of a waterfall, pool, and a
freshwater stream. For foraging and feeding enrichment, there will be live fish in the stream that
will be released randomly throughout the day. Since previous studies have found feeding
enrichment only lasts as long as the food lasts, it will not be the only source of enrichment and
feeding is recommended to be done in the mornings to prevent stereotypical behavior in the
afternoon. Other forms of enrichment have been discussed throughout the proposal and it is
recommended to have various inedible objects for manipulat ion that can be rotated daily and
safety hazards should be taken into consideration. Adding different scents into the enclosure such
as prey scents or food items can encourage foraging behavior and exploration.
In order to provide a positive visitor experience, the indoor portion of the exhibit will
contain the indoor wading pool, an Imax/Dome, and several informational slideshows throughout
the exhibit. Providing an Imax/Dome inside the exhibit can be used for visitor education and
awareness regarding conservation, global warming, and what they can do to help the cause. This
may also increase the viewing time of the polar bears and create a stronger connection to the
species. The first step to conservation is providing education and awareness.

17. Hoang 17
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Website References:
http://www.merriam-webster.com/