Island Life: Use of Activity Budgets and Visibility to Evaluate a Multi-Species Within-Zoo Exhibit Move

Simple Summary Modern zoos aim to provide the best facilities possible for their animals, staff and visitors. Here, we present findings from a study focusing on the behaviour and visibility of four species pre- and post-translocation to a new environment, Islands, within Chester Zoo, UK: the Sumatran orangutan (Pongo abelii), crested macaque (Macaca nigra), Malayan tapir (Tapirus indicus) and the Malayan sun bear (Helarctos malayanus). We used full activity budgets to demonstrate that the move to new, custom-built facilities influenced the behaviour of all four species. Following relocation, both non-human primate species were found to spend more time interacting socially with group members and abnormal behaviours remained low for all four species. Malayan tapirs and crested macaques chose to spend more time in areas out of public view post-move, whilst Malayan sun bears were more visible to visitors in their new environment. We demonstrate the value of giving animals choice and control over how they interact with their surroundings, the importance in investment in behavioural monitoring throughout translocation events and add to the knowledge-base of this understudied area. Abstract Modern zoos strive to construct habitats which both enable and encourage animals to engage in species-specific behaviour, without compromising their visibility to visitors. Here, we present the findings of a within-zoo move to a custom-built exhibit (Islands at Chester Zoo, UK) with respect to the behaviour of four mammal species; the Sumatran orangutan (Pongo abelii), crested macaque (Macaca nigra), Malayan tapir (Tapirus indicus) and the Malayan sun bear (Helarctos malayanus). We used full activity budgets along with Compositional Data Analysis (CoDA) to gain insight into how the move to a more naturalistic exhibit influenced behaviour. Engagement in abnormal behaviour remained low during the study period for all four species, suggesting no adverse responses to the change in environment. Following the move, both the non-human primate species spent more time engaged in positive social interactions with conspecifics, highlighting the importance of social support during enclosure moves. Time spent visible to the public was largely unaffected by the enclosure move for the Sumatran orangutan, whilst the movement to a new environment increased visibility for the Malayan sun bear and decreased visibility for the crested macaque and Malayan tapir. We demonstrate the value of monitoring behaviour throughout the translocation of zoo-housed species and outline the positive behavioral impacts of providing individuals with naturalistic, species-appropriate environments.


Introduction
Successful exhibit design can enable modern zoos to achieve many of their strategicand conservation-related objectives by providing species-appropriate habitats for their Table 1. Study species, subjects and data collection periods. Females represented by ♀, males represented by ♂.

Exhibit Information
All areas and volumes provided are approximations, based on exhibit drawings (Appendix B).

Sumatran Orangutan Exhibit Information
During the pre-move condition, this species was held in Realm of the Red Ape-a custom-built orangutan facility constructed in 2007 (Appendix B, Figure A1). Individuals had access to three indoor areas, each with an area of 145 m 2 and a cubic volume of 1435 m 3 . Indoor areas focused on providing vertical, three-dimensional space to facilitate arboreal activity. Additionally, individuals had access to two open-air outdoor exhibits (1385 m 2 and 1170 m 2 ). Species-appropriate features included mesh ropes, hammocks and wooden poles to encourage arboreal locomotion. During the post-move condition, this species was housed within Monsoon Forest, an area including a biodome within Islands. Here, individuals had access to two indoor enclosures (totalling 303.5 m 2 area, 1816 m 3 volume), one open air outdoor enclosure (1096 m 2 area) and one netted outdoor exhibit (300 m 2 area, 2450 m 3 volume) (Appendix B, Figure A2). A further indoor area (200 m 2 area, 910 m 3 volume) and one further open-air exhibit (2000 m 2 area) were made available to this species after the post-move data collection ended. Species-specific enclosure features included fiber-glass sway poles, larger artificial tree climbing structures, custom mesh hammocks to increase nesting and resting opportunities, varying height levels throughout indoor environments and heavy planting [29][30][31].

Crested Macaque Exhibit Information
Throughout the pre-move data collection period, this species was housed in the Monkey House exhibit. Individuals had access to one indoor (120 m 2 area) and one outdoor open-air 'island' area totalling 1496 m 2 (Appendix B, Figure A3). Visitors had nearly 360 • viewing opportunity for this species, particularly in the indoor area. The Monkey House exhibit included bark substrate flooring inside to prolong feeding behaviour and wooden poles connected with ropes and straps to encourage climbing. In the post-move data collection phase, this species was held in another part of Monsoon Forest, with access to one indoor enclosure (149 m 2 area, 6258 m 3 volume) and one open-air outdoor exhibit (2050 m 2 ) (Appendix B, Figure A4). Species-specific features included multiple wooden poles connected with strapping, dynamic multi-level indoor space supplemented with climbable artificial rocks on the walls [32,33] and off-show areas where individuals could choose to be away from the view of visitors.

Malayan Sun Bear Exhibit Information
Malayan sun bears were held in the Spirit of the Jaguar exhibit during the pre-move data collection phase. The savannah style of this exhibit comprised one indoor (800 m 2 ) and one outdoor facility (1130 m 2 ), with off-show den area access (two dens of 9 m 2 each) (Appendix B, Figure A5). Wooden structures were included within the exhibit to facilitate climbing behaviour. The custom-built facility for Malayan sun bears in Islands included access to one indoor on-show area (98 m 2 ), four indoor off-show den areas (8 m 2 each totalling 32 m 2 ), one off-show cubbing den (8 m 2 ) and two on-show open air outdoor areas (1420 m 2 and 870 m 2 ) (Appendix B, Figure A6). Species-appropriate facilities include wooden poles of various heights to encourage climbing [34], a cubbing den, a dry 'river-bed' area with rocks providing a different substrate [35] and heavily planted zones to provide natural refuge sites from visitors.

Malayan Tapir Exhibit Information
Malayan tapirs were held in the Cattle House exhibit at Chester Zoo during the premove data collection condition. This area comprised indoor stall housing (178 m 2 area) with an outdoor paddock (930 m 2 ) (Appendix B, Figure A7). Individuals were provided with a shallow water area for bathing, but this pool was not deep enough for individuals to be fully submerged. Visitors had a 360 • viewing opportunity for this species in the Cattle House. During the post-move condition, individuals had access to two indoor areas (one off-show: 110 m 2 , one on-show: 144 m 2 ) and two outdoor open-air paddocks (655 m 2 and 311 m 2 , including a 37 m 2 pool area) (Appendix B, Figure A8). Species-appropriate facilities included two large pools for swimming, deep enough to allow full submersion, bark substrate flooring and live trees and shrubs in the outdoor paddocks to increase the complexity of the environment [36,37]. Individuals were able to move away from public viewing areas within this exhibit, with off-show pens and a dividing wall which allowed refuge from visitors.

Data Collection and Preparation
The data were collected by four observers for use in different sub-projects (one researcher per species). As such, data collection methods (including ethograms and sampling methods) varied by species: Sumatran orangutan and Malayan sun bear data were collected using continuous focal sampling, Malayan tapir data using group instantaneous scan sampling at 1 min intervals, and crested macaque data using focal individual instantaneous sampling at 30 s intervals [38]. All data were collected via live in-person observations during staff working hours between 08:30 and 17:00 using species-specific ethograms (Appendix A, Tables A1-A4).
All observations were conducted at public viewing areas, with the researcher following subjects using these viewpoints throughout the observation session or until subjects entered an 'off-show' area which was out of sight. Risk assessment protocols were in place with contingencies outlined if the observer noticed that subjects were directly responding to observer presence, e.g., change clothing or abandon observation session. These contingencies were not utilized for any species within the study.
To prepare these data for analysis and to enable comparison between species, all data were coerced into a consistent sampling format: focal individual instantaneous sampling at 1 min intervals. For example, the behavioural state was extracted every minute from continu-Play Excitable, non-aggressive, playful behaviour: includes running, pursuit, mock-fighting, bucking and leaping. Can be alone or with another individual.

Rest
Individual is observed sitting, lying, or standing without movement.

Negative social interaction with conspecific
Aggressive and/or threatening behaviour between individuals. Includes slapping, hitting, displacement, charging and antagonistic facial expressions.

Positive social interaction with conspecific
Affiliative behaviour between individuals: Includes allogrooming, maternal behaviour, contact-sitting, nuzzling, mating and affiliative facial expressions.

Vigilance
Individual is observing/scanning and aware of surroundings; eyes and/or head in movement.

Not visible
Individual is not visible from observer's viewing position.
These standardised data were organized into 3 conditions: 'pre-move' (collected over a 3-7.5 month range) when individuals were housed within the core zoo, immediately prior to their move; 'early-post' (the 28 days after transfer to new environments); and 'post-move' (collected over a 0.5-4.25 month range) after the initial 28-day period, when individuals were in their new environments. The 'early-post' condition was included so that any behavioural changes that occurred during an initial habituation/exploration period would be distinguishable from a longer-term response seen in the 'post-move' condition (see prediction P3 above). As the timeline for data collection varied between species, 28 days was chosen as the cut-off between the 'early-post' and 'post-move' condition to allow for a consistent evaluation of the immediate effect of translocation across all species. Additionally, data were plotted and inspected over time, revealing a more consistent behavioural response after the 28-day period, suggesting that individuals had settled into their new environment after this time. This yielded a total of 36,085 sampling points (representing 601 h and 25 min sampling time) over 290 observation days and 1255 observation sessions (Table 3 and Figure 1). Due to the purely observational nature of the research performed, no ethical approval for research was required. However, study methods and protocols were approved by Chester Zoo's internal scientific review process.

Data Analysis
To investigate how the enclosure move influenced species' behaviour, we examined the data across the three enclosure-move conditions in two different ways: (1) by comparing visible activity budgets (Activity budget approach: predictions P1 and P3) and (2) by comparing the proportion of the observation time spent out of sight of the observer/public (Choice and control approach: prediction P2). The four species were examined separately throughout the analysis, and all of our response variables were expressed as proportions of the total observation time. All data analysis was conducted in R (version 4.1.0) [39] To investigate whether the enclosure move influenced species' activity budgets, we

Data Analysis
To investigate how the enclosure move influenced species' behaviour, we examined the data across the three enclosure-move conditions in two different ways: (1) by comparing visible activity budgets (Activity budget approach: predictions P1 and P3) and (2) by comparing the proportion of the observation time spent out of sight of the observer/public (Choice and control approach: prediction P2). The four species were examined separately throughout the analysis, and all of our response variables were expressed as proportions of the total observation time. All data analysis was conducted in R (version 4.1.0) [39]).

Activity Budget Approach (Models 1 to 4)
To investigate whether the enclosure move influenced species' activity budgets, we fitted four linear mixed models (LMMs) with gaussian error distributions and identity links using the package 'glmmTMB' [40]. For our response variables, we calculated the proportions of time allocated to each behaviour described in Table 2, excluding not visible. For each individual, within each observation session (our sampling block/observational unit), we divided the number of instantaneous sample points recorded for each behaviour by the total number of sample points recorded. When an individual's behaviour was recorded as other or not visible, these observations were discarded and subtracted from the total number of sample points.
Because activity budget data, by their nature, sum to 1 (or 100% if using percentages), the proportions of time spent in each activity are not independent. However, these types of data are habitually analysed as if each behavioural component were independent and unconstrained, e.g., by modelling the proportion of time spent performing each behaviour one-by-one, which can bias interpretation. When the response variable comprises more than two categories, this approach is inappropriate and can lead to spurious interpretation. Therefore, the activity budget data were analysed simultaneously using compositional models (Compositional Data Analysis (CoDA)). We transformed the proportional response variables using a centred log-ratio (CLR), which is the log of the ratio between the observed proportions of time spent performing each behaviour and their geometric mean per observation period. This removes the range restriction and allows for meaningful inference of the results of subsequent mixed models. Because the CLR transformation cannot handle zeros in the dataset, we first rescaled our proportions using the following formula, recommended for use when response variables are beta distributed [41]: where x is the observed proportion and length(x) our sample size. We used the CLR-transformed proportions as compositional responses in our four byspecies LMMs. To account for our first hypothesis (P1) that enclosure moves would influence activity budgets, we included as fixed effects behaviour (factor with up to 14 levels) and its two-way interaction with the enclosure-move condition (factor with 2-3 levels).

Choice and Control Approach (Models 5 to 8)
To investigate whether the enclosure move influenced the proportion of time that species spent out of sight of the public/observer, we fitted two Beta general linear models (GLMs) and two Beta generalized linear mixed models (GLMMs) with logit links using the package 'glmmTMB' [40]. The Beta distribution is typically used to model continuous proportion data, and the logit link function ensures positive fitted values that range from 0 to 1 [42]. For our response variables, we calculated the proportions of time that each species spent out of sight. For each individual, within each observation session (our sampling block/observational unit), we divided the number of instantaneous sample points recorded as not visible by the total number of sample points recorded. Because these response variables comprised only two categories (out of sight vs. visible), Beta regression was used rather than CoDA: Beta regression models proportions at the original scale, which makes statistical inference simpler [43]. Prior to analysis, we rescaled our proportions using the formula detailed in Section 2.4.1, recommended for use when response variables are Beta distributed [41].
We used the not visible proportions as responses in four, by-species Beta regression models. We included as fixed effects the enclosure-move condition (factor with 2-3 levels), which accounted for our second hypothesis (P2) that enclosure moves would influence the proportion of time that species spent out of sight of the public/observer.

Model Control Variables
All models included the same control variables: sex (factor with two levels: female, male) and age (continuous with range 281-10,749 days since birth). Age was scaled and centred prior to analysis. To incorporate the dependency among observations of the same individuals, and among observation sessions, the Sumatran orangutan and crested macaque models included crossed random intercepts for individual and observation sessions. Because the inclusion of random effects terms with fewer than 5 levels can destabilise mixed models, the Malayan tapir and Malayan sun bear models (three and four) only included the random intercept for the observation session, and for models seven and eight, no random effects were included. We weighted the four models with the total number of instantaneous sample points per species to account for the likely relationship between response accuracy and sample size.

Model Assumptions and Additional Information
We used a full model approach throughout, and model fit and assumptions were verified by plotting residuals versus fitted values with the package 'DHARMa' [44]. We determined the significance of the fixed effects using likelihood ratio tests. We fitted full and restricted models (models in which the parameter of interest, the fixed effect, are withheld, i.e., fixed to 0) and based test statistics on comparisons of the full model with the restricted models. The significance of the likelihood ratio test statistic was calculated using a chi-squared distribution with the appropriate degrees of freedom. Where appropriate, post-hoc tests were carried out using Tukey's HSD (honestly significant difference) tests, with the package 'emmeans' [45]. All statistical tests were two-tailed with α set to 0.05.

Effect of the Enclosure Move on the Visibility (Choice and Control Approach)
Overall, the null model significantly differed from the full model for crested macaques (χ2 = 30.202, df = 4, p < 0.001, Model 6), Malayan sun bears (χ2 = 20.923, df = 3, p < 0.001, Model 7) and Malayan tapirs (χ2 = 89.09, df = 4, p < 0.001, Model 8), indicating that the move to a new environment influenced the visibility of these species in public viewing areas. However, the null model did not significantly differ from the full model for Sumatran orangutans (χ2 = 1.581, df = 4, p = 0.812, Model 5), suggesting that visibility was not influenced by a move to a new environment for this species.

Model 5: Effect of the Enclosure Move on the Sumatran Orangutan Visibility
Sumatran orangutans spent similar proportions of time out of sight of observers/public before, immediately after (28 days) and following the enclosure move ( Figure 6; Appendix C Table A10).

Effect of the Enclosure Move on the Visibility (Choice and Control Approach)
Overall, the null model significantly differed from the full model for crested macaques (χ2 = 30.202, df = 4, p < 0.001, Model 6), Malayan sun bears (χ2 = 20.923, df = 3, p < 0.001, Model 7) and Malayan tapirs (χ2 = 89.09, df = 4, p < 0.001, Model 8), indicating that the move to a new environment influenced the visibility of these species in public viewing areas. However, the null model did not significantly differ from the full model for Sumatran orangutans (χ2 = 1.581, df = 4, p = 0.812, Model 5), suggesting that visibility was not influenced by a move to a new environment for this species.

Model 5: Effect of the Enclosure Move on the Sumatran Orangutan Visibility
Sumatran orangutans spent similar proportions of time out of sight of observers/public before, immediately after (28 days) and following the enclosure move ( Figure 6; Appendix C Table A10).

Model 6: Effect of the Enclosure Move on the Crested Macaque Visibility
Crested macaques spent significantly more time out of sight of observers/public immediately after (28 days) and following the enclosure move ( Figure 6; Appendix C Table  A11) than pre-move.  Table A12).

Model 8: Effect of the Enclosure Move on the Malayan Tapir Visibility
Malayan tapirs spent more time out of sight of observers/public following the move (in the 28 days post-move and thereafter) than before the enclosure move (Figure 7; Appendix C Table A13).

Model 6: Effect of the Enclosure Move on the Crested Macaque Visibility
Crested macaques spent significantly more time out of sight of observers/public immediately after (28 days) and following the enclosure move ( Figure 6; Appendix C Table A11) than pre-move.

Model 7: Effect of the Enclosure Move on the Malayan Sun Bear Visibility
Malayan sun bears spent less time out of sight of observers/public in the 28 days post-move than before the enclosure move ( Figure 7; Appendix C Table A12).

Model 8: Effect of the Enclosure Move on the Malayan Tapir Visibility
Malayan tapirs spent more time out of sight of observers/public following the move (in the 28 days post-move and thereafter) than before the enclosure move ( Figure 7; Appendix C Table A13).

Discussion
Activity budget comparison during a management or environmental change is often used to assess whether an intervention has influenced animal behaviour [3,23,26,46]. Here, we presented activity budgets for four species during three periods of data collection: pre-move, early-post and where available, post-move. In line with our first prediction (P1), the move to a new environment significantly affected the activity budget of all species. Furthermore, the visibility of three of the four species to members of the public was also influenced from pre-move to post-move as predicted (P2). Additionally, in support of prediction 3 (P3), we found evidence that activity budgets differed significantly between the early-post and post-move conditions, indicating that there was a period of habituation to the new environment. We show here the value of presenting and considering full activity budgets when evaluating the influence of an environmental change, as it allows an examination of the relative change in the proportions of expressed behaviour.

Activity Budget Approach
Our study revealed consistent behavioural responses across study species. For example, abnormal behaviour remained low, absent or declined in all four species. The absence of abnormal, repetitive behaviours is generally used as an indicator of positive welfare

Discussion
Activity budget comparison during a management or environmental change is often used to assess whether an intervention has influenced animal behaviour [3,23,26,46]. Here, we presented activity budgets for four species during three periods of data collection: pre-move, early-post and where available, post-move. In line with our first prediction (P1), the move to a new environment significantly affected the activity budget of all species. Furthermore, the visibility of three of the four species to members of the public was also influenced from pre-move to post-move as predicted (P2). Additionally, in support of prediction 3 (P3), we found evidence that activity budgets differed significantly between the early-post and post-move conditions, indicating that there was a period of habituation to the new environment. We show here the value of presenting and considering full activity budgets when evaluating the influence of an environmental change, as it allows an examination of the relative change in the proportions of expressed behaviour.

Activity Budget Approach
Our study revealed consistent behavioural responses across study species. For example, abnormal behaviour remained low, absent or declined in all four species. The absence of abnormal, repetitive behaviours is generally used as an indicator of positive welfare [47]. However, because some of these behaviours can be "learned" in potentially sub-optimal previous enclosures (and so may not reflect current welfare experience), the use of abnormal behaviour as a measure of enclosure suitability should be interpreted with caution [48,49]. Additionally, an absence of abnormal behaviour does not necessarily mean that the animal's welfare is optimal [2]. Despite this, zoos often strive to reduce or eliminate abnormal behaviours by encouraging the expression of species-typical behaviour through good husbandry practices [50,51], naturalistic feeding regimes [26,52] and/or enhancing enclosure environments [52].
Our results also indicated a consistent increase in the expression of positive social behaviour with conspecifics for both primate species from pre-to post-move. Positive social interactions such as allogrooming and play are vital for social cohesion and the maintenance of group structure in many primates [53,54], with investment in this behaviour often prioritized after periods of disturbance [55]. Allogrooming can function as a form of stress prevention (social buffering) in crested macaques, with reductions in self-directed behaviour and aggressive tendencies observed after grooming sessions [56]. Similarly, observing allogrooming may also promote the expression of other positive social behaviours (e.g., Macaca sylvanus [53]), highlighting the importance of these behaviours at the individual and group levels. Despite this, research into the effects of translocation on pro-social behaviour is limited. However our findings are in line with those reported by Schaffner and Smith [56], that Wied's marmosets (Callithrix kuhlii) tend to seek a partner's proximity more after an enclosure move than before. From pre-to post-translocation, grooming rates fell among tufted capuchin monkeys (Cebus apella), but the mean number of grooming partners increased [57]. Our work adds to the body of literature highlighting the importance of maintaining species-appropriate social groups during translocation events, as they have the potential to play a key role in both individual and group level welfare.

Sumatran Orangutan Activity Budget
Individuals were observed engaging in less feeding and more locomotor behaviour following the exhibit move. The decrease in time spent feeding from the pre-to post-move condition could be attributed to individuals investing more time in maintaining group social relationships over time [58], whilst the increase in locomotion early-post-move is likely an exploratory response to the novel environment. Social interaction with humans decreased from pre-move levels of 10.2% (±2.0) of the activity budget to 0.1% (±0.1) postand early-post move. Visitors can be a source of stressful excitement for zoo-housed primates [59], with reported increases in activity correlating with visitor number [60]. When we examined which category of humans the orangutans interacted with (keepers vs. visitors), we found that the reduction in time spent interacting with humans was largely driven by a reduction in time spent interacting with visitors (6.5% pre-move to 0.0% post-move). Notably, two hand-reared female orangutans were responsible for the majority of the visitor interactions, highlighting the importance of early-life-history context in assessing welfare. Visitors tend to perceive interactions with orangutans as positive experiences (K.Finch, pers comms); however, it is important to provide animals with the opportunity to avoid such interactions, and thoughtful enclosure design can enable this [61]. Additionally, individuals still had opportunities and areas to engage with visitors in their new environment, indicating that during both the early-post and post-move conditions, individuals were choosing to engage in other behaviours elsewhere. Orangutans often use and manipulate objects as tools [62]. This species-specific behaviour, defined here as 'object use', increased following the move to the new enclosure; from 3.4% of the activity budget pre-move to 7.3% post move. Novel planting and vegetation were available in the new environment, and these were often used to reach other resources within the area. Encouraging the expression of species-appropriate behaviour in zoo-housed individuals is essential in the optimization of animal well-being [63], and thus categorization of these behaviours is important in the evaluation of the welfare state.

Crested Macaque Activity Budget
Crested macaques spent less time feeding and locomoting, but more time engaged in positive social behaviour and autogrooming following the enclosure move. Self-directed behaviours in primates such as scratching, self-grooming and face touching are associated with physiological and psychological arousal (often stress) [64][65][66]; however, such gestures may also serve a communicative function [67]. Group members may gain insight into an individual's motivational state by observing their self-directed behaviours, such as self-grooming, allowing them to better mediate their social interactions [68]. However, the increase in self-grooming was accompanied by an increase in positive social interaction with conspecifics, suggesting that affiliative social bonds between individuals may mediate some of the stressful effects associated with a period of uncertainty [69]. Upon comparison to pre-move values, it was observed that positive social behaviour increased during the early-post-move condition whilst autogrooming increased during the post-move condition. The difference in the latency of responses could be due to the adoption of both shortand long-term coping strategies to the move to a new environment by this highly social species. Macaques also spent less time resting immediately following the enclosure move (during the early-post-move condition), but the percentage of time spent resting returned to pre-move levels after the initial four weeks had passed. A shift towards more active behaviours during the early-post-move phase could be attributed to a process of habituation to the novel environment, with similar patterns observed in both zoo-housed [70] and wild primates [71]. Our results show that species natural history should be taken into consideration when evaluating the influence of an exhibit move on behaviour. For highly social species such as the crested macaque, the social dynamic and group composition may be more influential to overall activity budget than environment complexity or naturalism.

Malayan Sun Bear Activity Budget
Law & Reid [62] highlight the importance of appropriate enclosure design for zoohoused bear species, outlining that good husbandry practice, including a variety of targeted enrichment techniques, should work in harmony with well-designed architecture to optimize bear welfare.
Malayan sun bears were generally less active following the enclosure move in this study. Individuals spent less time foraging and locomoting and more time engaged in resting behaviour between the pre-move and post-move condition. Additionally, individuals reduced their time exhibiting abnormal behaviours by 5.5% from pre-to post-move. Malayan sun bears housed in enriched outdoor environments showed a similar pattern of behaviour [72], with increased resting and reduced stereotypy compared to bears kept in more barren environments. Bears are known to exhibit a range of abnormal repetitive behaviours in zoos [62], with management practices, such as feed regimes, and previous experience, i.e., mother or hand-reared, found to be directly linked to stereotypy occurrence [73]. Both individuals in this study were bought into captivity as a consequence of the illegal wildlife trade (T Rowlands, pers comms); therefore, this could have some influence on the behavioural repertoire observed during the study. Exhibit size and complexity have also been associated with behavioural and physiological benefits in polar bears (Ursus maritimus), showing that larger land areas and the ability for individuals to view out of their exhibit resulted in lower stereotypy engagement [74]. The outdoor environment in the new Islands exhibit is larger for this species than the previous facility, and this combined with species-appropriate features such as wooden climbing poles and varying environmental substrates (Appendix B, Figure A6) could have influenced the behavioural changes observed from pre-to post-move. However, it must be taken into consideration that our sun bear data only cover the pre-and early-post-move conditions; as such, these behavioural responses could be a short-term response to a new environment. For example, explorative behaviour increased by 6.6% during the early-post-move condition, suggesting that individuals spent time familiarizing themselves with the novel environment.

Malayan Tapir Activity Budget
Active behaviour increased following the enclosure move for Malayan tapirs. Recent work on zoo-housed Malayan tapirs is limited; however, activity budgets for zoo-housed South American tapirs (Tapirus terrestris) mainly comprise rest, feeding, foraging and locomotion [75]. We found that tapirs spent more time feeding and foraging following the enclosure move. This is largely consistent with the findings of Arumugam et al. [76], who highlighted that enclosure type had a significant influence on feeding behaviour for this species, with increased feeding observed in naturalistic vs. artificial environments. This suggests a measure of success for the Islands expansion as the tapir enclosure was designed to be more naturalistic and environmentally complex than their previous enclosure, with the specific aim of facilitating the expression of natural active behaviours. Prior to the enclosure move, the tapirs spent the majority of their time resting (62.7% (±3.9) of their activity budget). Following the enclosure move, this reduced by 39.4% to 23.3% (±2.9). However, this decrease should be interpreted with caution as the tapirs were also considerably less visible post-move, and it is plausible that resting time remained consistent but unrecorded. Changes in activity levels have also been reported in several other species after a move to a new environment [10,[77][78][79][80][81], and it is possible that any decrease in time spent resting could be attributed to exposure to a novel area, i.e., time spent exploring increases at the expense of rest. However, by separating our analyses into three blocks (one of which should encompass this habituation/exploration period; early-post-move), we can be largely confident that the post-move behaviour changes represent a longer-term response. For example, although an increase in non-repetitive locomotor behaviour may be attributable to an individual exploring their new habitat [77], care should be taken to record if this behaviour becomes excessive or follows a specific route (route-tracing), as this could be indicative of locomotor stereotypy [82,83]. When we examined which behaviours comprised 'Locomotion', we found that swimming increased from 0.05% of the activity budget to 4.7% following the move to the Islands enclosure. Tapirs are one of few semi-aquatic hoofed animals, thus access to an appropriate water source is suggested to be essential for their welfare [84]. The pool in the pre-move enclosure was not deep enough for individuals to fully submerge and swim, and this was key in the design of the new enclosure. As such, the Islands enclosure contained two larger pools (Appendix B, Figure A8). The expression of swimming behaviour for this species provides a clear example of the benefits and importance of considering species' natural behaviour during the enclosure design process.

Choice and Control Approach
Modern animal welfare assessment highlights the importance of allowing individuals to exercise a level of choice and control over their environment [20]; for zoo animals, this includes the amount of time that individuals spend in public view. Our study revealed that for three of the four species studied, the move to a new environment influenced the time that individuals spent visible to the public. Malayan sun bears spent more time in public viewing areas immediately following the move (early-post-move condition). Conversely, crested macaques and Malayan tapirs spent less time visible to the public following the enclosure move. Both species had little choice in their pre-move environments regarding being visible to the public. However, once given the facilities in their new environment to be out of public view, our data showed that the crested macaques and Malayan tapirs utilised these areas. The transition to a new environment did not influence the amount of time spent in public viewing areas for Sumatran orangutans.
Research into human-animal relationships (HARs) has increased in the last decade with a variety of positive, neutral and negative welfare outcomes reported from HARs in zoo-settings [85][86][87][88][89][90][91][92]. Visitors play an important role in this dynamic, with many expressing their enjoyment at observing natural behaviour and learning about zoo-housed species, yet visitors often state they want to do so in close proximity to the animals themselves [52]. This presents an interesting conflict of interest for zoo managers, as there is increasing evidence outlining the behavioural and welfare benefits of giving animals a level of agency within their environment and daily lives [93]. Ritzler et al. [94] outlined that when provided with environmental choice, individuals increased locomotor and other active behaviours compared to when they were restricted. Furthermore, Ross [95] reported that access to off-exhibit holding space decreased stereotypy and increased social play in a pair of captive polar bears (Ursus maritimus). When investigating the relationship between animal behaviour and visitor perception at a Chinese zoo, animal presence elicited a similar visitor response at both naturalistic and barren exhibits. However, visitor interest persisted at the naturalistic exhibit even when animals were not visible [96]. Given that enclosures with a naturalistic design are suggested to provide a more suitable environment for zoohoused species [97], institutions may be able to ensure optimal animal welfare by allowing them to exert a level of choice and control over their environment, whilst maintaining visitor satisfaction.
A potential limitation of this research was controlling for other factors which may affect behaviour such as weather [98], seasonality [99][100][101], observer influence [102,103] and visitor presence [96,104,105]. Any future research should consider collecting these variables. Remote behavioural monitoring through networked cameras has been shown to provide a non-invasive, observer-free insight into behaviour through periods of change for zoo-housed species [106] and so should be considered if possible. However, the interaction between these variables must also be examined when considering the influence they may have on behaviour. Goodenough et al.
[107] outlined that both time and weather can lead to the overestimation of visitor effects, a finding which needs to be considered for when future work is conducted in this area.

Conclusions
In line with our first prediction (P1), the move to a new environment significantly altered engagement in pre-determined behavioural categories for all four species studied. Using compositional data analysis, we were able to investigate the relative change in the proportion of certain behaviours over time following the move to a more naturalistic environment. In line with our second prediction (P2), we revealed that time spent in areas visible to the public changed for three of the four species following translocation. Finally, we highlight the importance of including a habituation period when conducting behavioural observations during the evaluation of these management events. In line with our final prediction (P3), engagement in certain behavioural categories did change across all species between the early-post and post-move condition, indicating individuals had a period of time in which they transitioned and adapted to their new areas. By gaining insight into the proportion of time spent in specific behaviour categories using activity budgets and compositional data analysis, we can infer that the new environments provided in the Islands expansion are successful in facilitating species-appropriate behaviours whilst still providing viewing opportunities for visitors.  Institutional Review Board Statement: Ethical review and approval were waived for this study due to purely observational and non-invasive nature of behavioral data collection. The project was internally approved by senior animal and science directorate staff at Chester Zoo through their internal review process.

Informed Consent Statement: Not applicable.
Data Availability Statement: Data available upon request.

Acknowledgments:
The authors would like to extend their thanks to Andrew Moss, Tim Rowlands, Chloe Cain, Ian Hickey, James Powell and Freddy Child for their valuable contributions and support throughout this study. The authors would also like to thank three anonymous reviewers for their useful feedback. Additionally, this study would not have been possible without the support from Chester Zoo's animal keeping staff, in particular the Primate, Carnivore and Giraffe teams.

Conflicts of Interest:
The authors declare no conflict of interest.

Sexual
Includes heterosexual mounting and copulation, the presentation of the anogenital region to another individual or the inspection of the anogenital area to solicit mating.

Positive social interaction with conspecifics
Solitary play Excitable behaviour which has no specific outcome or objective, includes swinging on ropes and interacting with enclosure resources in a playful manner.

Play
Tool use Utilisation of objects within the environment to achieve a specific task.
Object manipulation

Visitor interaction
Sitting by or looking through visitor windows, includes reacting to visitors by banging the glass using fists or objects within the enclosure.

Social interaction with keeper/visitors
Vocalising Exhibiting one or a combination of calls which could include a kiss squeak, long call, whimper or rolling call.  An individual clasps the haunches of a partner with both hands and grasps its legs with feet as in a mount.

Social positive
Huddle Groups of ≥ three individuals embracing.
Social positive

Lipsmacking
The lips are pursed, and the lower jaw is moved up and down rapidly and rhythmically. The jaw may be thrust upward. The mouth may be slightly open with the tongue moving back and forth. The lips often produce an audible sound. Alternatively, the mouth may be closed, and sometimes the teeth knock together. Eyelids are generally half-lowered. The scalp may be retracted and the ears flattened. The display is used during affiliative interaction. It may also end a conflict and acts as an appeasement or reassurance signal.

Social positive
Mating An individual climbs ventrodorsally upon a standing partner and inserts his erect penis in the female's genitals. The mounter may or may not grip the legs of the partner.

Social positive
Play An individual contacts another in the context of play. This may include touching, slapping, bumping, jostling, pushing, grasping, catching, chasing, pulling, nibbling, dragging, lifting, climbing or leaping over the partner, along with other patterns possibly occurring outside the context of play (e.g., mount, mouth approach). These patterns are accompanied by silent bared-teeth facial expressions. Play behavior is distinguished from conflict by a lack of loud vocalizations. Table A2. Cont.

Behaviour Definition Combined Behaviour Category
Resting Individual is observed sitting, lying, or standing without movement. Individuals are not interacting with others, but may be in physical contact with them.

Silent bared-teeth
The upper lip or both lips are vertically retracted, exposing the teeth and sometimes the gums.
The corners of the mouth may be drawn back. The jaw may be either closed or opened to various degrees. The scalp is often raised and the ears flattened. This is an affiliative display; it is commonly observed during affiliative interactions and social play.

Social positive
Window licking An individual is observed licking the glass-viewing panels. Abnormal              Appendix C