The effect of hiding enrichment on stress levels and behaviour of domestic cats (Felis sylvestris catus) in a shelter setting and the implications for adoption …

Abstract

This study investigates the effect of hiding enrichment on stress and behaviour of kennelled cats. Forty-three cats were studied either with a BC SPCA Hide & Perch™ box as enrichment, or with an open bed as control. Observations consisted of Stress Score, approach test and scan sample, recorded daily over the five days following a cat's entrance into the adoption centre, and again on the 14th day if the cat was still present. Days until adoption was noted for cats adopted during the study period. A survey was given to adopters of study cats in an attempt to determine the motivations underlying their choice of cat.
A significant reduction in stress was noted between all study days in the enriched group. Stress levels in this group declined further between the fifth and the 14th day, while those of the control group increased. Cats in the enriched group were significantly more likely to approach and displayed relaxed behaviours much more frequently. No significant difference was found between the two groups in days until adoption, percentage adopted, or in the reasons provided by the new owners in the adoption survey; however temperament was found to be the highest ranked reason for choosing a cat from either group.
Results of this study suggest that the welfare of kennelled cats is greatly improved if they are provided with the opportunity to perform effective hiding behaviour, and that the ability to perform such a behaviour does not decrease the likelihood of those cats being adopted.

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© 2007 Universities Federation for Animal Welfare
The Old School, Brewhouse Hill, Wheathampstead,
Hertfordshire AL4 8AN, UK
Animal Welfare 2007, 16: 375-383
ISSN 0962-7286
The effect of hiding enrichment on stress levels and behaviour of domestic
cats (Felis sylvestris catus) in a shelter setting and the implications for
adoption potential
K Kry*† and R Casey‡
†38 Spokane Street SW, Calgary, Alberta, T2W 0M5, Canada
‡Department of Clinical Veterinary Science, University of Bristol, Langford, Bristol BS40 5DU, UK
* Contact for correspondence and requests for reprints: klkry@yahoo.ca
Abstract
This study investigates the effect of hiding enrichment on stress and behaviour of kennelled cats. Forty-three cats were studied either
with a BC SPCA Hide & Perch
™
box as enrichment, or with an open bed as control. Observations consisted of Stress Score, approach
test and scan sample, recorded daily over the five days following a cat’s entrance into the adoption centre, and again on the 14th
day if the cat was still present. Days until adoption was noted for cats adopted during the study period. A survey was given to adopters
of study cats in an attempt to determine the motivations underlying their choice of cat.
A significant reduction in stress was noted between all study days in the enriched group. Stress levels in this group declined further
between the fifth and the 14th day, while those of the control group increased. Cats in the enriched group were significantly more
likely to approach and displayed relaxed behaviours much more frequently. No significant difference was found between the two
groups in days until adoption, percentage adopted, or in the reasons provided by the new owners in the adoption survey; however
temperament was found to be the highest ranked reason for choosing a cat from either group.
Results of this study suggest that the welfare of kennelled cats is greatly improved if they are provided with the opportunity to perform
effective hiding behaviour, and that the ability to perform such a behaviour does not decrease the likelihood of those cats being
adopted.
Keywords:adoption, animal welfare, behaviour, cat, hiding enrichment, stress
Introduction
In the past, most research in the field of animal welfare
focused on those animals used for production or maintained
in a zoo setting. In recent years however, increasing
attention has been given to welfare issues of domestic
animals kept as companions. The cat (Felis sylvestris catus)
has recently become the most popular pet, with 8 million
owned in the UK alone (Rochlitz 2000) and attention to
welfare issues of this species is emerging. Among the
general population, the largest welfare issue for companion
animals is believed to involve some sort of intentional abuse
(Watt & Waran 1993). Although heinous, this type of crime
does not affect a large proportion of the animal population
and therefore may not be truly considered as the largest
issue (Podberscek 1997). One of the larger issues concerns
the quality of life of those cats without a home (Rukavina
2001). Whether a cat is a stray or, for one reason or another,
it becomes unwanted by its owner, its destination is
typically some form of kennel or shelter system. Although
the number of healthy cats euthanised in these systems is an
ethical rather than a welfare issue, the lives of those animals
while they are within the system is very much a welfare
issue. It is the responsibility of the people involved in the
management of such facilities to ensure the favourable
welfare of the animals while present.
Stress is a normal aspect of life and is experienced by all
living animals (Dawkins 1998). Problems arise when the
amount of stress experienced by an animal exceeds a certain
level and becomes distress. At this point, the coping mech-
anisms of the animal are no longer adequate (Moberg 2000)
and there are serious implications for the animal’s welfare.
Biological functions may be impaired, such as decreased
fertility and immunosuppression (Archer 1979).
Psychological impacts may also be noted, often manifested
in abnormal behaviours such as stereotypies or self-mutila-
tion (Wechsler 1995; Toates 2000). It is for this reason that
stressors, especially those created by human intervention,
should be minimised.
Entrance into a shelter system may be an extremely stressful
experience for a cat and may lead to levels of distress.
Previously, the cat would have lived in a home situation or
as a stray or feral, spending its life freely outdoors.
Whatever the cat’s origin, it is likely that the shelter system
presents several aspects of novelty. A new environment that
contains new people, new animals, and new smells
contributes to the novelty of the situation. A cat may feel
Universities Federation for Animal Welfare Science in the Service of Animal Welfare

376 Kry and Casey
mere curiosity when exposed to a novel stimulus provided
it is otherwise comfortable and some degree of familiarity
exists (Holmes 1993). When exposed to an entirely novel
situation, however, on average, cats will experience stress to
some degree (Levine 1985). In addition to the stress
resulting from novelty, stress is also created through the act
of being confined, and the inability to perform many natural
behaviours (Landsberg 1996). Although some kennels have
an excellent standard for cage size, it is unlikely that even
these large enclosures are comparable to the size of home
range, be it a house or outdoor territory, previously enjoyed
by the cat (Heidenberger 1997). Procedures such as de-
worming and de-fleaing, as well as more invasive proce-
dures such as neutering, are often routine in shelter systems.
Although these processes are designed to aid the cat, they
are also quite likely to result in stress. Shelters often meet
exceptional standards for care of an animal’s physical
health, however, the assurance of positive psychological
health may be minimal.
It is unlikely that the need for shelters will be completely
eliminated at any point in the near future. Millions of cats
worldwide will continue to be exposed each year to the
inevitable stressors associated with shelters. It is, therefore,
crucial that the focus be on minimising this stress through
enrichment and providing the cats with a situation that
better helps them cope with their new environment.
Forms of enrichment which have been investigated in the
past and which are used in shelters include both social and
inanimate enrichment. Although there is individual
variation in cats as to preference for any type of enrichment,
many generalisations can be made. Upon initial entrance,
enrichment should focus on allowing effective coping
behaviours for acute stress, such as provision of perching
areas (Rochlitz 1999). Proper use of a synthetic formula of
feline facial pheromone has been found to be effective in
reducing anxiety (Griffith et al 2000). The husbandry
routine of the shelter also has an impact on the cat’s ability
to adapt. By performing tasks such as cleaning and feeding
at similar times of day the cat may come to expect when
certain events will happen. Predictability has been shown to
be of great importance in reducing stress levels of many
animals (Carlstead et al 1993b). The structure of the kennel
itself is of importance and details ranging from material
used for its construction (Smith et al 1994) to interaction
with elements outside the kennel (Newberry 1995) can
influence welfare. Factors such as reduced transit time to
the shelter and time between entrance to the shelter and allo-
cation to a kennel have also been shown to influence time
required by a cat to adapt to the shelter (McCune 1994).
Social contact with either people or conspecifics influences
the welfare of the cat (eg Kessler & Turner 1999a). If the cat
is properly socialised, interaction with others can greatly
improve its welfare. However if the cat is not socialised,
then contact results only in further stress production.
Generally, frustration resulting from boredom and limita-
tions on the opportunity to engage in natural behaviours
leads to the development of chronic stress (McCune 1994;
Toates 2000). Enrichment devices that attempt to alleviate
this type of stress include toys and feeding enrichment such
as puzzle feeders (McCune 1995). The novelty of such
stimuli is extremely important to their effectiveness, and
therefore these devices must be continually changed.
The ability to hide is a necessity for cats when exposed to a
stressor (eg McCune 1994; Smith et al 1994; Rochlitz
2000). However, when a shelter considers enrichment for a
cat, this method may often be overlooked. The argument
commonly presented is that if a cat takes advantage of the
opportunity to hide, its visibility to the public is limited. As
it is less likely to be seen by the public, it is less likely to be
adopted. Therefore, even if the animal’s short-term welfare
may improve through the provision of such enrichment, it is
theorised that the effect on adoption potential more than
counteracts this benefit. This, however, may be a miscon-
ception. When a cat is better able to cope with a stressful
situation it is usually more adaptable, extroverted and
friendly (Loveridge et al 1995), making it an even more
likely candidate for adoption (Turner 2000).
To date, no research has been found for which the primary
goal was to determine the effects of hiding enrichment on
stress in shelter cats, or whether this enrichment affects the
adoption potential of the animal. Secondary observations
have noted that an attempt to hide resulted in reduced stress
levels (Carlstead et al 1993b) and that cats showed a prefer-
ence for hiding enrichment (Smith et al 1994). Preliminary
observations suggest that cats provided with a hiding box
have reduced stress, adapt more readily to a shelter, perform
more natural behaviours, and appear more ‘friendly’ (Soules
2002). However, none of these studies determined if proper
hiding enrichment would decrease stress beyond that of
conventional housing designs.
The purpose of this study was to determine the effect of
hiding enrichment on stress levels of cats at initial exposure
to a shelter system. The impact of hiding enrichment on the
likelihood of adoption of these cats was also investigated.
Materials and methods
Animals and environment
Forty-three domestic short-hair cats were studied at
Kirkintilloch Cats Protection Adoption Centre. Upon arrival
at the shelter, the cats were allocated to either the enriched
group or the control group. Randomisation was achieved by
allocating alternate cats entering the shelter into the two
treatment groups. Twenty-two cats were allocated to the
enriched group, consisting of 14 females and eight males,
ranging from six months to 18 years of age (median age six
years). The other 21 cats were allocated to the control
group, consisting of 13 females and eight males, ranging in
age from one to 15 years (median age seven years).
Enriched and control kennels were located randomly
throughout the adoption centre. Cats generally arrived at the
adoption centre between 1400 and 1700h. Day one of data
collection was the day following the cat’s arrival, as a
minimum of two hours adjustment is required for accurate
© 2007 Universities Federation for Animal Welfare

Hiding enrichment and stress in the domestic cat 377
Cat Stress Scores to be achieved (Kessler & Turner 1997).
All cats in this study were housed singly in pens that
consisted of an indoor area containing a water dish, a food
dish and a toy, and an outdoor area, containing a shelf and
litter tray. The outer portion was accessible through a cat
door in the back wall of each indoor section. The front doors
of the kennels were made of transparent plexi-glass, such
that views of the inside of the adoption centre as well as
visual contact with cats housed across the hallway, were
possible. As the walls of each pen were solid the cats were
unable to view their neighbour, although auditory and
olfactory communication were possible. A single tier
system existed, such that all kennels were located at the
same height. Indoor portions of kennels of enriched cats
contained a BC SPCA Hide & Perch™ box (a two-tiered
cardboard box with a lower hiding space ([53 × 30 × 22 cm;
length × breadth × height] with two access openings, and an
open upper sitting area [53 × 30 × 9 cm;
length × breadth × height] [supplied by the BC SPCA, BC,
Canada]) as well as a heating pad and duvet. Indoor sections
of kennels of control cats contained a ‘bed’ (an open plastic
basket, measuring 60 × 40 × 10-18 cm;
length × breadth × height) with a heating pad and duvet.
Data were collected for each cat between 1530 and 1630h,
except where otherwise noted, on days one through five as
well as day 14 for any cat that remained in the kennel at that
time. The same observer collected all data, which consisted
of a Cat Stress Score, scan sample and approach test.
Adoption data were also collected for any study cat homed
during the course of this study.
Cat Stress Score
Cats were assigned daily Stress Scores according to the Cat
Stress Score system developed by Kessler and Turner
(1997). This scoring system ranks the level of stress
perceived in the cat based on observations of its posture and
behaviour as described in the ethogram devised by the UK
Cat Behaviour Working Group (1995). The scores range
from one (no stress) to seven (extreme stress). Cats were
assigned an initial score, with a second score given on
reassessment following 15 minutes of no interaction. The
two scores were then averaged to assign the cat its daily
Stress Score. The change in score between day one and each
of the other observation days was determined for the
purposes of analysis.
Approach test
Two approach tests were used on each cat, separated by
15 minutes of no interaction. In the first approach test, the
observer stood 10 cm in front of the closed doors of the
kennel. The initial reaction of the cat was noted as approach,
retreat, or no reaction. The latency of the cat to approach the
front of the kennel was also recorded, up to a maximum
time of 60 seconds. If the cat was located at the front of the
kennel at the start of the test, the observer stood at the
opposite side and latency to approach was determined as the
time taken by the cat to approach that opposite side of the
kennel. Cats that did not approach were assigned maximum
time scores of 60 seconds. The same data were recorded for
the second approach test, which was conducted in a similar
fashion to the first approach test, except in this test the doors
of the kennel were opened. To maintain consistency in the
tests, no noises or actions were made by the observer during
either of the approach tests. Change in latency to approach
between days one and five was determined for analysis as
an increase, decrease, or no change.
Scan sample
Scan samples were taken twice daily for each cat. The first
reading occurred between 1300 and 1400h, while the public
was allowed access to the cats. The second recording was
taken between 1530 and 1630h, after the shelter was closed
to the public. General observation was made of the cat’s
location in the kennel; either in or on the BC SPCA Hide &
Perch™box/bed, behind the BC SPCA Hide & Perch™
box/bed, or elsewhere in the kennel. Activity was also noted
as restful sleep, alert rest (differing from restful sleep by
constant attentiveness to external stimuli), sitting, or active
(all other activities involving movement). Location and
activity results were totaled over all study days for the
purposes of analysis.
Adoption
A record was kept of the number of days the cat was present
in the adoption centre before being adopted, for those cats
that were adopted by the end of the observation period. A
survey was given to adopters in order to assess the impor-
tance of various factors in deciding which cat to adopt.
Factors included age and sex of the cat, appearance of the
cat and kennel, and temperament of the cat. Each item of the
survey consisted of a number scale of one to five, with one
being strongly disagree, three being neutral, and five being
strongly agree. A space was also provided for the adopter to
list additional factors that were considered important in
choosing their specific cat. Adoption data were collected for
an additional two-week period following the end of other
observations. This time scale was decided upon by
averaging the days until adoption of cats adopted earlier in
the experiment. Any cats not adopted by the end of this
additional period were given a maximum score of 60 days
for analysis purposes.
Statistical analysis
Due to the non-normal distribution of the data, non-para-
metric statistics were used to analyse continuous data.
Mann-Whitney Utests were used to analyse the change in
Cat Stress Score, latency to approach, and adoption data.
Chi-square tests were used to analyse approach reaction,
change in latency to approach, and scan samples, due to the
categorical nature of the data. Data from all cats of one
group were combined as previous studies have found that
there was no statistically significant difference in results
obtained from cats of different sex, age, or breed (Kessler &
Turner 1997). Data were analysed using Minitab
version 13.32.
Animal Welfare 2007, 16: 375-383

378 Kry and Casey
Results
Cat Stress Score
Differences were noted between the two treatment groups in
the median Stress Score found on each observation day
(Figure 1). As there was already a significant difference
noted on day one of data collection, analysis of the Stress
Score noted on individual days gives unclear results with
regards to the effect of the enrichment on stress. This effect
is better determined through an analysis of the change in
Stress Score over the study days, thus negating the initial
difference between treatment groups. Between day one and
each subsequent observation day, a significant change in
Stress Score was noted for the enriched group compared to
the control group (Figure 2). Stress Score changes between
day one and two were found to have a significant difference
(w= 459.0, P= 0.0003). The median change in Stress Score
for the enriched group was -0.75, and 0.25 for the control
group, indicating an average increase in stress in the cats of
the control group, while that of the enriched group had
decreased. The median change in Stress Score for the
enriched group between days one and three was -1.00, and for
the control group was -0.25 which was also significant
(w= 582.5, P = 0.0009). A significant difference between
the groups was found between days one and four (w=
502.5, P= 0.0009). The median change in Stress Score for
the enriched group was -1.37 and for the control group was
-0.50. Between days one and five, a significant difference in
Stress Score change was also noted (w= 574.0, P= 0.0005).
The median change in Stress Score for the enriched group
was -1.75 and for the control group, the median difference
was -0.75. Two weeks after the cats first arrived in the
shelter, a significant difference was still noted for change in
Stress Score between the two groups (w= 110.0, P=
0.0059). The median change in Stress Score for enriched
cats was -2.25, and for control cats was -0.375.
Approach tests
Approach test 1: kennel door closed
Initial reaction:
A significant difference was noted between the reaction of
the enriched and the control cats throughout all observation
days (χ2= 9.686, df = 2, P= 0.008). Enriched cats
approached more often, with a total of 18 percent of
reactions being approach. They also retreated less often,
with only one percent of reactions noted as retreat. The
control cats, however, were less likely to approach and more
likely to retreat, with only 10 percent approaching, and
eight percent retreating.
Latency to approach:
No significant difference in latency to approach was noted
between the two groups on any of the observation days.
This is due perhaps to the high proportion of cats that did
not approach and were therefore assigned maximum time
scores of 60 seconds resulting in skewed data. Cats of either
group that did approach showed a continued decrease in
latency throughout the days with a slightly larger decrease
noted for the enriched cats (latency median for enriched
group = 37.5 seconds on day one, 5.0 seconds on day five;
latency median for control group = 17.5 seconds on day
one, 12.5 seconds on day five). However, this change was
not found to be significantly different (χ2= 1.22, df = 2,
P= 0.543)
Approach test 2: kennel door open
Initial reaction:
Throughout all observation days, the enriched group
approached 32 percent of the time, and retreated nine
percent of the time, while 59 percent of the time showing no
reaction. Cats in the control group approached 25 percent of
the time and retreated 14 percent of the time, while
61 percent of the time showing no reaction. These differ-
ences, however, were not found to be significant (χ2 = 2.213,
df = 2, P= 0.331).
Latency to approach:
No significant difference in latency to approach was noted
between the groups on any of the observation days,
although a much higher proportion of cats were observed to
approach at some time when compared to approach test 1.
For cats that did approach, those in the enriched group
showed a decrease over days while those in the control
group remained constant (latency median for enriched
group = 21.0 seconds on day one, 2.0 seconds on day five;
control group = 5.0 seconds on day one, 5.0 seconds on day
five). Again, this difference in change was not significant
(χ2= 5.411, df = 2, P = 0.067).
Scan samples
Activity
A significant difference was noted between the activities of
the two groups totaled over all observation days (χ2= 8.152,
df = 3, P= 0.043). The cats in the enriched group were
sleeping restfully more often than those in the control
group. Sleep consisted of 20 percent of all observed activi-
ties in the enriched group, as compared to the control total
of 11 percent. Control cats were resting alert and sitting
more often than the enriched cats. Seventy percent of activ-
ities of the control cats were alert rest, and 14 percent
sitting, while these totals were 65 percent and nine percent,
respectively in the enriched group. Active behaviours were
identical in both groups, comprising six percent of all
behaviours observed for each group (Figure 3).
Location
A significant difference was noted in the location of the cats
in the two groups during the scan samples indicating a pref-
erence for the BC SPCA Hide & Perch™box over the
control bed (χ2= 34.248, df = 2, P < 0.001). Cats in the
enriched group were observed either in or on their BC
SPCA Hide & Perch™ box 77 percent of the time, and
located elsewhere in the kennel 23 percent of the time. At no
time were any of the cats attempting to hide behind their BC
SPCA Hide & Perch™box. Cats in the control group used
their basket 61 percent of the time, and were located
elsewhere in the kennel 39 percent of the time. Thirty-six
© 2007 Universities Federation for Animal Welfare

Hiding enrichment and stress in the domestic cat 379
percent of these instances occurred when the cat was
attempting to hide out of view behind its basket (Figure 4).
Days until adoption
No significant difference was noted in the number of days
required for adoption of cats in the enriched group as
compared to the control group (w= 388.5, P= 0.977).
Twenty-one percent of enriched cats were adopted, with a
median of 12 days. Twenty percent of control cats were
adopted with a median of 13 days.
Adoption survey
No significant difference was found between the two groups
for ratings of the various questions on the adoption surveys.
The median score for the importance of sex or age of the cat
was 3.0 for the enriched group and 4.0 for the control group,
Animal Welfare 2007, 16: 375-383
Figure 1
Median Stress Score (± interquartile) of cats in enriched and control treatments on each observation day.
Figure 2
Median change in stress score (± interquartile) of cats enriched and control treatments between later observervation days and day one.

380 Kry and Casey
however this difference was not significant (w= 59.0,
P= 0.3545). The median score for the importance of
physical appearance of the cat was 4.0 for the enriched
group and 3.5 for the control group, and again, this differ-
ence was not significant (w= 73.0, P = 0.6234). The median
score for importance of the appearance of the kennel was
3.0 for the enriched group and 2.5 for the control; this
difference was also not significant (w= 74.0, P= 0.5484).
For both groups, the temperament of the cat was the most
important factor. This was slightly more so for the enriched
group (median score 5.0) than the control group (median
score 4.5), however the difference between the two groups
was not significant (w = 71.5, P= 0.7234).
Other influencing factors were listed for four of the adopted
cats, three from the control group and one from the enriched
group. Alternative reasons listed included suitability with
children (enriched cat), indoor nature of the cat, lack of
allergic reaction, and sympathy.
Discussion
Cat Stress Score
Results of this study support previous suggestions that
hiding enrichment is beneficial for cats entering a novel or
otherwise stressful environment (Smith et al 1994; Rochlitz
1999; Soules 2002). Enriched cats showed much lower
stress levels than control cats. The implications of the
significant decrease in Stress Score noted between the two
groups are extremely important to the welfare of cats main-
tained in any captive environment.
It may be presented that the reduced stress could be the
result of the provision of perching areas rather than, or as
well as, hiding areas. Due to limitations of resources, it was
not feasible to have a study group that was allowed access
to only a hiding area. Any hiding enrichment device placed
in a kennel would inevitably provide a perching area on top.
In order to provide a hiding area alone, the top of the enrich-
ment would need to connect to the ceiling of the enclosure,
or the area would need to be formed directly into a wall of
the kennel. However, although it has been stated that the
provision of perching areas can aid in stress reduction, such
perches are generally a great height above ground level.
This height provides the cats with a viewing location that
allows them to effectively scan their surroundings
(Rochlitz, 1999). The impact on stress levels from the slight
elevation of 22 cm provided by the perch of the BC SPCA
Hide & Perch™boxes may be considered minimal.
Kessler and Turner (1999b) suggested that a Stress Score of
lower than three is acceptable as this merely represents a
baseline level of stress present in any living animal. An
elevation above this level represents the response to an
acute stressor and is not a problem if these levels are not
sustained. That is, if either the stressor is removed or the
animal is able to cope successfully with the stress (Moberg
2000). The results from the control group show that these
animals were maintained at a relatively high stress level.
Only study day five showed a median stress score of less
than three, with the median score rising above this value
again by day 14, indicating that the stressor had not been
removed for the majority of the animals. The fact that
enriched cats had an acceptably low Stress Score, obtaining
and maintaining a score of less than three as of the third
study day, indicates that these animals were able to cope
effectively with this stress. The increase of stress in the
control group after two weeks is potentially indicative of the
development of chronic stress. This work has not assessed
chronic stress; however, the absence of this increase in the
enriched group, suggests that coping effectively with the
acute stress first encountered upon entry into the shelter,
may prevent chronic stress from occurring.
Approach test
The results of this study clearly indicate a higher incidence
of approach by a cat to a person at their kennel when the cat
is provided with hiding enrichment. Although a cat has the
ability to hide, and may utilise such facilities in order to
cope more effectively with stress, it is also more likely to
leave its enclosure and approach a person present at its
kennel. A cat that responds by approaching a potential
owner, even through a closed door, projects a more
favourable personality (Turner 2000).
Although no significant difference was found for the cats to
approach when the cage door was open, this may be due to
the fact that this second test, although performed after a
time of no interaction, was still performed following the
first test for which significant results were obtained. In
previous studies, a similar problem was noted, whereby the
interest in the observer by the cat appeared to have dimin-
ished by the second trial of the day (Hoskins 1995). It is this
decreased interest, rather than an increased fear or stress
response that resulted in the cat’s lack of reaction.
Scan sample
Carlstead et al (1993b) noted a behaviour in their study cats
which they termed ‘attempting to hide’. This consisted of
the cat attempting to conceal itself as much as was possible
with the resources available. Control cats in this experiment
were often observed performing this type of behaviour,
typically by crouching behind their beds. It is reasonable,
based on the appearance of these cats and the description
given by Carlstead et al, to presume that they too were
attempting to hide. This actually made them less visible to
the public than a cat hiding in its BC SPCA Hide & Perch™
box. In addition, this coping strategy was apparently inef-
fective at reducing the stress experienced by the animal.
Smith et al (1994) noted a higher proportion of time spent
alert by cats not yet adjusted to a new environment.
Vigilance has often been associated with anxiety-related
behaviour problems in house cats. When a cat is anxious
about the presence of other cats, either inside or outside the
house, it may often be observed sitting vigilant in an area
where it can view these ‘intruders’ (Beaver 1992). Upon
visual confirmation of the presence of another cat, the stress
level of the already anxious cat will increase further and
behaviour problems such as spraying are a common result
© 2007 Universities Federation for Animal Welfare

Hiding enrichment and stress in the domestic cat 381
(Hart & Pedersen 1991). Results from this study confirm
this alert type of behaviour in cats with a higher stress level.
The cats of the enriched group appeared generally less
anxious as they performed more true resting behaviour
and less alert resting behaviour than did the cats of the
control group.
Adoption results
Days until adoption
No significant difference was found between the two groups
for the number of cats adopted or the number of days it took
for those cats to be adopted. The claim that providing hiding
areas to cats in adoption centres reduces their visibility to
the public and will therefore reduce the likelihood of their
adoption is not valid. This claim may be made with the best
intentions for the cat, hoping that faster adoption of the
animal results in the best welfare outcome. However, from
the stress results of this study, cats forced to stay in the
adoption centre without the ability to use a BC SPCA Hide
& Perch™box have a greatly reduced welfare while their
adoption potential is not actually improved.
Adoption survey
For both the control and the enriched group, the adopters
rated the temperament of the cat as being the main factor
influencing their decision to adopt the cat they chose. This
is an important factor to consider when deciding what
enrichment to provide to animals kept in shelters. Each cat
has its own distinct personality (Feaver et al 1986; Mendl &
Harcourt 2000), however, it is generally agreed that a cat
which is less stressed is more likely to portray ‘friendly’
characteristics and generally appear more appealing to a
potential owner (Turner 2000). The results of this study
agree with this statement. The enriched cats, which had
lower stress, approached more rapidly, hid behind kennel
furniture less, and spent less time actively resting. The
general public may interpret these behaviours as the cat
possessing a less nervous temperament. Although cats
provided with hiding enrichment might be slightly less
visible to the public, the portrayal of a more favourable
personality may counteract any resulting negative impact on
adoption potential.
Further applications
There are differing opinions of the long-term effects of
confinement on stress levels in cats. Field (2002) found a
significant increase in behavioural indicators of stress in
cats present in a shelter for eight weeks as compared to the
same cats tested after only two weeks. There were indica-
tions of the development of chronic stress after an initial
acute stress response had subsided. Rochlitz et al (1998),
however, found a significant decrease in physiological and
behavioural indicators of stress after five weeks in a quaran-
tine facility. In the quarantine facility, despite the drastically
reduced overall level of enrichment, the cats were provided
with a hiding area that was not made available to the cats in
the shelter system studied by Field. Results from this study
seem to suggest that the ability to hide delays, if not elimi-
nates, the chronic stress response, however the long-term
effects were not investigated beyond a two week time span.
It would be of interest to investigate if the cause of the
discrepancy between the previously mentioned studies is
the result of better adaptation through the provision of
hiding enrichment. If this coping mechanism proved
effective at minimising both acute and chronic stress, it
would have crucial implications for the welfare of cats
maintained in a captive environment, be it a shelter, a quar-
Animal Welfare 2007, 16: 375-383
Figure 3
Proportion of total observation in which cats of the a) enriched
and b) control treatments engaged in various behaviours.
Figure 4
Proportion of total observations in which cats of the a) enriched
and b) control treatments were noted in various locations.

382 Kry and Casey
antine facility or a laboratory, and may be applicable to non-
domestic cats maintained in zoos, as suggested by Carlstead
et al (1993a).
It may also be interesting to investigate the effects of this
type of enrichment on pair- or group-housed animals. In the
pilot study for this experiment it was noted that when a pair
of cats were given a BC SPCA Hide & Perch™box, one
would often sleep in the hide portion while the other slept in
the perch. This effectively allows for increased resting areas
for the cats without occupying increased floor space, which
is generally limited in shelters. By increasing resting areas
in such a way, there may be a reduction in stress caused by
competition for resources between group-housed animals
(Heidenberger 1997). It may alternatively be the case that
with the provision of only one hiding area there could be an
increase in competition for that resource, resulting in
increased stress levels. This could only be determined
through further investigation.
Animal welfare implications
Cats are exposed to a number of stressors upon entering a
captive facility such as a shelter. The welfare of the animal
depends on its ability to cope effectively with these
stressors. The natural instinct of a cat when exposed to a
threatening situation is to retreat, however if physical
removal is not possible, then it will attempt to conceal itself
from view. By providing cats entering an adoption centre
with enrichment that allows them to perform this coping
behaviour, a drastic reduction in stress is observed. The
likelihood of the cat being adopted is no different if it is
given this enrichment, however its welfare while in the
adoption centre is greatly improved.
Acknowledgements
The authors would like to thank Cat’s Protection for the use
of their facilities at Kirkintilloch Adoption Centre and for
funding the second author. We are also grateful to the staff
at the Kirkintilloch Adoption Centre for their help and
support. Great thanks go to the BC SPCA for provision of
the BC SPCA Hide & Perch™boxes. We would also like to
thank Donna Brander for her insightful suggestions and
editing and the referee of this paper for thoughtful
comments. Thanks are given to the University of Edinburgh
for the opportunity for one of the authors to pursue an MSc
in Applied Animal Behaviour and Animal Welfare, for
which the research reported in this paper was partial fulfill-
ment of the requirements.
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