Review of the Effects of Enclosure Complexity and Design on the Behaviour and Physiology of Zoo Animals

Future Aviary Design: The Science of Circular Flight Aviaries for Avian Welfare

Birds are kept in captive settings globally, and many of these birds are not flight-restrained. It is generally considered more ethical to house birds in aviaries than to practice flight restraint through wing clipping or pinioning, which means that aviaries are needed to prevent birds from escaping. Traditionally, rectangular aviaries are commonly used; these aviaries may not be well designed for bird flight, especially for large-bodied species. In this paper, we draw attention to the circular flight aviary, a design which has the potential to encourage extended flight in captive birds without the need for excessively large exhibit design. Several circular flight aviaries are already used in select zoos globally, but there is at present, limited empirical evidence on the welfare benefits for birds. We evaluate the tools that are required to assess the effects of circular flight aviary design on bird welfare, with a focus on aspects of exercise physiology that are sometimes overlooked in traditional welfare assessments. The circular design may also be used to overcome challenges associated with breeding birds in complex social structures, such as those which benefit from being housed in large flocks yet are intolerant of other individuals when nesting. Circular flight aviaries, if developed with a view to generating an evidence base, have the potential to improve bird welfare, at a time when bird flight is becoming more restricted globally due to disease implications.

Effect of Feeding Environmental Enrichment on Lesser Anteaters' Behavior, Space Use and Food Selectivity

Studying behavioral response to management and housing conditions provides specific evidence to enhance animal welfare. Feeding environmental enrichment (FEE) is a powerful strategy to meet welfare challenges. Lesser anteaters' (Tamandua tetradactyla; n = 7) response to FEE was assessed by analyzing behavior and space use through focal sampling every 5 minutes/24 hours using cameras. Study 1 (S1): space use of enclosure zones (shelter = SZ, climbing structures = CSZ and ground = GZ) was characterized without FEE during 5 days using the modified Spread of Participation index (SPI). Study 2 (S2) used an ABA experimental design during 18 days (A=pre- and post-enrichment and B = enrichment). The FEE was applied in CSZ, the least utilized zone revealed in S1. S1: The lesser anteaters utilized the zones differently (modified SPI = 0.74 ± 0.02), and stayed mostly in the GZ. S2: An increment in feeding during FEE was detected, but it did not modify total activity, most natural behavior, repetitive locomotion or space use. The electivity index indicated that the routine diet was over-utilized and enrichment items were under-utilized. The provision of enrichment items created new foraging opportunities, improving the behavioral domain of animal welfare.

Life beyond a jar: Effects of tank size and furnishings on the behaviour and welfare of Siamese fighting fish (Betta splendens)

Globally, Siamese fighting fish (Betta splendens) continue to be sold and kept in small, barren jars or tanks, with little concern for their welfare. This study aimed to examine the impact of housing size and furnishings (i.e. live plants, refuges) on the behaviour of Siamese fighting fish, to understand optimal tank conditions. Thirteen male Siamese fighting fish were rotated between five different housing conditions: 'jar' (1.5 L); 'small' (3.3 L); 'medium' (5.6 L); 'large' (19.3 L); and 'large-barren' (19.3 L). All tanks had gravel and furnishings, except the large-barren tank which was devoid of these. Overall, tank size influenced behaviour. Fish were significantly more active and spent significantly less time resting and performing 'abnormal' behaviours (hovering and stereotypic swimming), in the large tank compared to the smaller tanks. Tank furnishings also influenced behaviour. Fishes in the large-barren tank performed more 'abnormal' behaviours (hovering, stereotypic swimming, interaction with the walls), compared to the large tank which had furnishings. These results suggest that the small, barren jars and tanks that Siamese fighting fish are often housed in are detrimental to their welfare, and larger, furnished tanks are more optimal. Behavioural variations were observed between the fish in this study, highlighting individual fish personality. We recommend a minimum tank size of 5.6 L for the display and sale of Siamese fighting fish, and tanks larger than this for keeping Siamese fighting fish at home. All tanks should contain gravel, live plants and refuges.

Tarantula welfare may be improved with greater environmental complexity: A preliminary behavioral study with Brazilian black tarantulas (Grammastola pulchra)

Increased environmental complexity has positive effects on the welfare status of vertebrates living in human care; however, this line of research has received little focus in invertebrates. Here we conducted a preliminary investigation of Brazilian black tarantula (Grammastola pulchra) behavior in relation to environmental complexity. Using a counterbalanced design, we housed tarantulas in both Standard and Complex environments. Complex housing was differentiated from Standard by being approximately six times larger and containing six times as many structural elements. We evaluated (1) how does tarantula behavior differ between these two housing conditions, (2) does housing affect tarantula behavior in a novel environment test, and (3) do tarantulas prefer one housing condition over the other? Activity budgets were approximately equivalent between the two housing conditions with inactivity accounting for nearly all observed behavior. Home ranges and core areas were 77% and 113% larger in the Complex housing condition. When in a novel environment, tarantulas had 150% greater odds of being active after living in the Complex condition. Interestingly, the tarantulas showed no clear preference for either environment in the preference test. Our preliminary results suggest tarantula welfare may be improved with greater environmental complexity as demonstrated through more neophilic response to novelty and greater home range and core area size when living in Complex housing. However, it is worth noting that broad patterns of behavior were similar, no clear preference in housing was identified, and our study sample size was limited. Further research is needed to better understand the behavior and welfare of tarantulas, but this study demonstrates how established methodologies used in the study of vertebrates can be readily applied to invertebrates.

Cinereous Vulture (Aegypius monachus) Welfare Monitoring in a Breeding Center during the Breeding Season

One of the conservation measures of the globally near-threatened cinereous vulture is restoring populations via translocations, with some vultures originating from breeding centers. These centers need to have reproductive success, and securing good welfare levels should be a priority due to the negative implications a compromised welfare has on reproduction. Thus, assessing welfare in breeding centers is essential. Remote methods should be preferred, such as behavior analysis and use of space using camera systems. The study's first objective was to develop an activity budget that could be used as a baseline for detecting behavior irregularities. The second was to determine if behavior analysis and use of space could detect potential welfare issues in a breeding center. The study developed an activity budget that could be used as a standard for behavior analysis for the captive population. Behavior irregularities were detected, and the potential need to improve the enclosure and its surroundings were noticed. Altogether, the proposed methodology and results will contribute to the detection of possible welfare issues in breeding centers and, consequently, improve reproductive success and species' conservation.

Artificial Intelligence for Climate Change Biology: From Data Collection to Predictions

In the era of big data, ecological research is experiencing a transformative shift, yet big-data advancements in thermal ecology and the study of animal responses to climate conditions remain limited. This review discusses how big data analytics and artificial intelligence (AI) can significantly enhance our understanding of microclimates and animal behaviors under changing climatic conditions. We explore AI's potential to refine microclimate models and analyze data from advanced sensors and camera technologies, which capture detailed, high-resolution information. This integration can allow researchers to dissect complex ecological and physiological processes with unprecedented precision. We describe how AI can enhance microclimate modeling through improved bias correction and downscaling techniques, providing more accurate estimates of the conditions that animals face under various climate scenarios. Additionally, we explore AI's capabilities in tracking animal responses to these conditions, particularly through innovative classification models that utilize sensors such as accelerometers and acoustic loggers. For example, the widespread usage of camera traps can benefit from AI-driven image classification models to accurately identify thermoregulatory responses, such as shade usage and panting. AI is therefore instrumental in monitoring how animals interact with their environments, offering vital insights into their adaptive behaviors. Finally, we discuss how these advanced data-driven approaches can inform and enhance conservation strategies. In particular, detailed mapping of microhabitats essential for species survival under adverse conditions can guide the design of climate-resilient conservation and restoration programs that prioritize habitat features crucial for biodiversity resilience. In conclusion, the convergence of AI, big data, and ecological science heralds a new era of precision conservation, essential for addressing the global environmental challenges of the 21st century.

Impacts of visitors on female pheasants in pheasantry, Haripur, Pakistan

Background

The interaction between visitors and captive birds is complex, with a potential impact on bird's behavior and welfare. Understanding this interaction is essential for effective conservation and management.

Methods

We conducted a study at the University of Haripur's pheasantry in Khyber Pakhtunkhwa, Pakistan to investigate the effects of visitor numbers, duration of visitor presence, and climatic factors on the behavior of female pheasants. We observed the state and events of feeding, hiding, and moving behaviors of 16 randomly selected individuals from five species.

Results

The mixed-effects modeling results show that visitors (VT), visitors' presence duration (VPD), and temperature (TP), significantly influence feeding events (p < 0.001), feeding duration (p < 0.001), hiding events (p < 0.001) and hiding duration of female pheasants (p < 0.001). The moving events of pheasants were also significantly affected by both VT and VPD (VT: p = 0.002, VPD: p < 0.001). Moreover, under high visitor conditions, the impact of VPD on the behavior of female pheasants was more pronounced (p < 0.001). Additionally, our result reveals that different species of pheasants exhibit varying sensitivities to human factors and climatic factors. For instance, the two species of female pheasants with the highest feeding and hiding events were the Green pheasant (Phasianus versicolor) and the Ring-necked pheasant (Phasianus colchicus). While hiding duration of female Green pheasants, female Golden pheasants (Chrysolophus pictus), and female Silver pheasants (Lophura nycthemera) was longer than those of others. The mean number of moving events was highest in females of Ring-necked, followed by Golden pheasants. The female Indian peafowl (Pavo cristatus) and female Silver pheasants were the birds with the longest moving duration.

Conclusion

Our findings highlight the necessity for customized management strategies, to lessen the effects of human disturbances in pheasantries. For a thorough understanding of these interactions, more studies involving larger sample sizes and a wider variety of species are advised.

Moving Toward Evidence-Based Care: Measuring Preferences in Zoo-Housed Aquatic Turtles Using 24-h Remote Monitoring

Providing evidence-based care to animals is a common goal in zoos and aquariums. However, there are many understudied species with a lack of information available, which may result in suboptimal care for individuals of these species. Using preference tests to ask individual animals what they want can be an effective means to enhance their care, and subsequently, their welfare. Using 24-h remote monitoring, we assessed substrate, enclosure feature, and lighting preferences of five aquatic turtles (two wood turtles, one Blanding's turtle, and two spotted turtles) that share an indoor enclosure at Lincoln Park Zoo. In addition, we compared enclosure feature and lighting preferences between winter and summer to determine whether the turtles had changing seasonal preferences despite being housed indoors. We found that the wood turtles and Blanding's turtle had substrate preferences, whereas the spotted turtles did not. In addition, we found that the turtles' enclosure feature preferences were consistent between winter and summer, but the amount of time spent on land, logs, and in water varied by individual. Finally, we found that the turtles utilized areas with ambient lighting more than areas with a heat lamp or UV lamp; this was consistent between winter and summer. The turtle preferences observed in this study can contribute to the development of care strategies that support their welfare and, in turn, may inspire similar preference studies at other institutions as we collectively advance toward providing animals of all taxonomic groups with evidence-based care.

Leveraging camera traps and artificial intelligence to explore thermoregulation behaviour

Behavioural thermoregulation has critical ecological and physiological consequences that profoundly influence individual fitness and species distributions, particularly in the context of climate change. However, field monitoring of this behaviour remains labour-intensive and time-consuming. With the rise of camera-based surveys and artificial intelligence (AI) approaches in computer vision, we should try to build better tools for characterizing animals' behavioural thermoregulation. In this study, we developed a deep learning framework to automate the detection and classification of thermoregulation behaviour. We used lizards, the Rough-tail rock agama (Laudakia vulgaris), as a model animal for thermoregulation. We colour-marked the lizards and curated a diverse dataset of images captured by trail cameras under semi-natural conditions. Subsequently, we trained an object-detection model to identify lizards and image classification models to determine their microclimate usage (activity in sun or shade), which may indicate thermoregulation preferences. We then evaluated the performance of each model and analysed how the classification of thermoregulating lizards performed under different solar conditions (sun or shade), times of day and marking colours. Our framework's models achieved high scores in several performance metrics. The behavioural thermoregulation classification model performed significantly better on sun-basking lizards, achieving the highest classification accuracy with white-marked lizards. Moreover, the hours of activity and the microclimate choices (sun vs shade-seeking behaviour) of lizards, generated by our framework, are closely aligned with manually annotated data. Our study underscores the potential of AI in effectively tracking behavioural thermoregulation, offering a promising new direction for camera trap studies. This approach can potentially reduce the labour and time associated with ecological data collection and analysis and help gain a deeper understanding of species' thermal preferences and risks of climate change on species behaviour.

Effects of Enclosure Complexity and Design on Behaviour and Physiology in Captive Animals

Individual animals in managed populations are subject to controlled social and physical environmental conditions that impact their behaviour patterns, choice of social associates, ability to experience positive welfare states, and ultimately their overall health status and quality of life [...].

Quantifying animals' perception of environmental predictability using anticipatory behavior

Animals under human care often experience predictable daily husbandry events, which can promote the development of anticipatory behavior. Previous research suggests even short delays in the arrival of a predictable, desired outcome can lead to negative welfare outcomes for animals. As such, providing reliable information to animals regarding the onset of important events may be a simple but useful method to support positive welfare. Here we evaluated the quantitative characteristics of anticipatory behavior of a California sea lion at the San Francisco Zoo in three situations (1) when the animal had accurate information about the occurrence of the event (temporally predictable training sessions), (2) when the information was semi-reliable (unscheduled training session), and (3) when a reliable signal was offered before unscheduled sessions. Results showed that providing a reliable cue resulted in a stronger temporal correlation of anticipation before the beginning of the unscheduled session, similar to the temporally predictable training session. However, providing a reliable cue did not reduce the intensity of the anticipatory behavior. We propose to take into account two aspects of the quantitative characteristics of anticipatory behavior: correlation with time until a desired event (correlation) and intensity, where the correlation indicates the ability of an individual animal to predict the occurrence of an event, and the intensity indicates the degree of sensitivity of the animal to reward. We discuss the implications for animal welfare and husbandry.

Keeping reptiles as pets in Brazil: keepers' motivations and husbandry practices

BACKGROUND

Reptiles are considered one of the most popular pets in the world and are often associated with an incorrect belief that they are simple, highly adaptable, and easy to keep animals when compared with other pets, such as dogs and cats. However, keeping reptiles as pets can pose several challenges in meeting their needs in a domestic setting, requiring specific conditions and effort to maintain their health, well-being, and survival.

METHODS

During 2015, using online semi-structured questionnaires applied to 719 Brazilian pet reptile keepers who participated in online groups of reptile breeders on the social network Facebook, this study aimed to identify Brazilian keepers' motivations for maintaining reptiles as pets, investigate their monthly expenses, and the husbandry practices for the maintenance, such as housing and feeding conditions, handling of the animal, health issues, and treatment provided.

RESULTS

We found multiple motivations for keeping reptiles as pets (mostly snakes, lizards, and chelonians), the main motivation being emotional reasons, followed by entertainment and convenience reasons. The great majority of keepers (69%) declared to spend less than or up to US$30 per month in maintaining their reptiles. Most reptiles were kept alone in terrarium/aquarium enclosures, with basic environmental complexity in terms of physical elements. Lizards and chelonians were fed with a few insect species, cultivated fruits and vegetables, while snakes were fed mainly with domestic rodents, rabbits, or birds. Keepers declared frequent cleaning of the enclosure, but inappropriately handled their animals directly with their hands, which might result in potential threats to human and reptile health and safety. Several diseases or injuries were mentioned and 55.6% of the keepers declared taking the reptile to the vet for treatment.

CONCLUSIONS

Overall, our findings revealed several challenges that reptiles face when kept in domestic environments, including issues related to housing, nutrition, and healthcare. Even though keepers demonstrated positive feelings toward their pets, suggesting a positive relationship and a willingness to provide them with proper care, it seems that without the proper knowledge and awareness, reptiles may unintentionally be kept with poor husbandry. Addressing these challenges on husbandry practices is essential for improving reptiles' welfare and promoting a responsible pet ownership.

Effects of food-based enrichment on enclosure use and behavioral patterns in captive mammalian predators: a case study from an Austrian wildlife park

Background

Combining naturalistic enclosure design and animal welfare with visitor interests and education can be challenging for zoos and wildlife parks. To accomplish both purposes, different types of enrichment (food-based or non-food-based items, such as environmental, sensory, cognitive, social) can be used. The aim of the present study is to investigate the effect of food-based and olfactory enrichments on enclosure use, behavior, and visibility of captive brown bears (Ursus arctos), pine martens (Martes martes), domestic ferrets (Mustela putorius furo), and golden jackals (Canis aureus).

Methods

We used observational approaches to measure enclosure use, behavior, and visibility during three different experimental phases: (1) pre-enrichment (baseline, no experience with the enrichment yet), (2) during enrichment (enrichment was provided at low frequented locations in the enclosures that are easily visible to visitors), and (3) post-enrichment (enrichment was removed from the enclosures).

Results

We found that enrichment led to a uniform use of the enclosure and enhanced visibility in brown bears, increased activity budgets in pine martens, and observed high object interaction in both species. No effects of enrichment were detected in domestic ferrets. Golden jackals did not leave their burrows during daytime during the entire observation period; thus, observations were not possible at all. Our results suggest different effects of food-based enrichment, e.g., enclosure use, temporal activity patterns, and animal visibility. However, further studies should control for the specific role of the factors involved. Our study represents one of the first explorations of food-based enrichment in rather understudied species.