J. Zool. Bot. Gard., Volume 2, Issue 2 (June 2021) – 12 articles

The conservation status of great apes (chimpanzees Pan troglodytes, gorillas Gorilla sp., orangutans Pongo sp., and bonobos Pan paniscus) is grave and zoological institutions are vital for maintaining numbers of these species and educating the public about their importance. Technology provides tools that can assist zoos in meeting these objectives. However, the extant research on technology use in zoos is potentially constrained by small sample sizes and there is no framework detailing the methodologies necessary for the successful incorporation of technology into great ape management. Therefore, this study aimed to determine current technology use in the management of captive great apes and whether technology-directed behaviour differs between ape genera. Primary carers of great apes in zoos were surveyed using a 43-question, online questionnaire. The purpose of integrating interactive technology into captive ape management was primarily for enrichment (53% of respondents), followed by research (20% of respondents). However, only 25% of respondents had apes directly engaged with technology. There were no differences in technology-directed behaviours between ape genera. By identifying differences in practice, this research marks the initial stage in developing a best practice framework for using technology. Full article

Captive mammals respond emotionally toward cognitive challenges, but research has precluded marine mammals. A potential indicator of emotion in toothed cetaceans is a large singular bubble (‘burst’) emitted from the blowhole, previously linked to surprise and excitement. Our study analysed bursts from a published study on dolphin cognitive enrichment. Bursts were only produced by task-engaged (72%) or task-spectating (28%) dolphins (n = 6 males in total). Burst frequency increased with the proportion of task engagement and spectator frequency, but not task progress or success (providing no evidence for an instantaneous ‘Eureka moment’). Bursts were reduced in frequency over three weeks, consistent with a decrease in task-engagement. Bursts were significantly more likely to come at the start of a bout of task-engagement than in the middle or end. We suggest bursts were an emotional response signaling dolphins’ instantaneous judgement of the task, more likely related to positive affect (interest, curiosity) than negative affect (frustration). They appear unrelated to respiration. It was unclear whether bursts were produced consciously and had a social function. We call for further dedicated research on the emotional valence of cetacean bursts. This will require simultaneous behavioural and acoustic measurements under different levels of more controlled challenge. Full article

Defining the activity patterns and social relationships of animals can provide valuable information related to animal welfare. Bottlenose dolphins under professional care engage in a variety of social and solitary activities, which may be influenced by conspecifics, time of day, and maternal behaviors. This study examined the social, solitary, and maternal behaviors of eight dolphins at one zoological facility. Data about social and solitary behaviors, nursing occurrences, and mother–calf pair swimming were collected five days per week over a ten-month period. The simple ratio index was used to calculate association rates for all dyads. Affiliative behaviors were the dominant behavior class and all behavior categories and swim states showed temporal oscillations throughout the day. The high association values within the mother–calf dyads suggested these ties remain strong through the second and third years of life. Preferred associates remained the same for some individuals in both social group compositions, while they differed for others. However, no large reductions in associations were recorded, suggesting strong relationships in the subgroups continued when other individuals were present. Examining sociality and activity levels may be a useful tool in continuing to improve welfare as they may be related to social groupings and environmental factors. Full article

Stimulation of the thyroid with thyroid-stimulating hormone (TSH) is a potentially useful diagnostic of thyroid dysfunction, but little is known about the response of the thyroid to TSH stimulation in bottlenose dolphins (Tursiops truncatus). To better characterize the response of the dolphin thyroid to TSH stimulation, five adult dolphins participated in a TSH stimulation study. Dolphins voluntarily beached onto a padded mat and were given a 1.5 mg intramuscular injection of human recombinant TSH. Blood samples collected the day prior, at multiple intervals the day of, and daily for three days after the injection were analyzed via radioimmunoassay for free and total triiodothyronine (fT3 and tT3), and free and total thyroxine (fT4 and tT4). Significant increases in circulating fT3, fT4, and tT4 were observed with peaks occurring for all hormones the day after the TSH injection; maximal increases were 44%, 47%, and 23% for each hormone, respectively. Temporal patterns in the hormones potentially reflected feedback mechanisms countering the surge in fT3 following stimulation. Though recombinant human TSH was effective at stimulating hormone release, it is likely that use of dolphin or dolphin-derived TSH would enhance the clinical utility of the stimulation test, as would the development of antibodies specific to dolphin TSH. Full article

YouTube is the dominant online video-sharing platform and offers zoos an opportunity to engage a vast audience with conservation content. As there is limited research evaluating how zoos currently utilize YouTube, we cataloged and evaluated the content of 20 zoological organizations (focusing on the top 1000 most viewed videos from each channel) from 2006 to 2019. Separately, educational content in a subsample of the most viewed and recently produced videos from three zoo-YouTube channels was catalogued and evaluated for the period 2016 to 2019. We found that channels are becoming more focused on producing entertainment, rather than education-based content and not reflecting the taxonomic diversity of their animals. Videos containing conservation content may not be the most popular with the YouTube audience (making up only 3% of the most viewed videos), but there is evidence that outputs are becoming more conservation orientated, with more conservation-focused videos being produced over time. Zoos may be engaging with large audiences via YouTube, but should carefully consider how they represent different taxonomic classes and how they can create educational material in interesting and accessible forms. Full article

Zoos are one of the most visited tourist and leisure attractions. After all the important Central-European zoos closed in the spring of 2020 due to the COVID-19 pandemic, a few weeks later they started to re-open. The main goal of this article is to evaluate how the number of visits developed after the first zoo re-openings and what specific factors limited attendances the most after the reopening, using the example of Czech zoos in May and June 2020. In addition to the information available on zoos’ online communication channels, the authors’ questionnaire survey data and attendance data provided by the zoos were used. The results indicate that the attendance was reduced the most by the obligation to buy tickets online, by the closure of state borders, and by a low limit on daily maximum number of visitors allowed. Different approaches to restricting zoos’ capacity are discussed and the use of the maximum number of people by surface area of visitor routes at one time to limit attendance is recommended. In the future, this could be a key factor for sustainability of many zoos. Full article

Animal sounds are commonly used by humans to infer information about their motivations and their health, yet, acoustic data is an underutilized welfare biomarker especially for aquatic animals. Here, we describe an acoustic monitoring system that is being implemented at the U.S. Navy Marine Mammal Program where dolphins live in groups in ocean enclosures in San Diego Bay. A four-element bottom mounted hydrophone array is used to continuously record, detect and localize acoustic detections from this focal group. Software provides users an automated comparison of the current acoustic behavior to group historical data which can be used to identify periods of normal, healthy thriving dolphins, and allows rare instances of deviations from typical behavior to stand out. Variations in a group or individual’s call rates can be correlated with independent veterinary examinations and behavioral observations in order to better assess dolphin health and welfare. Additionally, the monitoring system identifies time periods in which a sound source from San Diego Bay is of high-enough amplitude that the received level at our array is considered a potential concern for the focal animals. These time stamps can be used to identify and potentially mitigate exposures to acoustic sources that may otherwise not be obvious to human listeners. We hope this application inspires zoos and aquaria to innovate and create ways to incorporate acoustic information into their own animal welfare management programs. Full article

Observational behavior research is an important activity for zoos and aquariums, often being conducted to provide insights into welfare and guide management decisions. This research relies on standardized protocols to ensure consistent data collection. Inter-observer reliability, where untrained observers are tested against the behavior identifications of an expert observer, represent a critical internal validation process. Recent software advances have made reliability testing easier and more accessible, but there is limited guidance on what constitutes a strong reliability test. In this study, we reviewed historic reliability test data from Lincoln Park Zoo’s on-going behavior monitoring program. Six representative species were chosen that included 645 live pairwise reliability tests conducted across 163 total project observers. We identified that observers were being tested on only approximately 25% of the behaviors listed and defined in the species ethograms. Observers did encounter a greater percent of the ethogram with successive reliability tests, but this gap remained large. While inactive behaviors were well-represented during reliability tests, social and other non-maintenance solitary behaviors (e.g., exploratory, scent marking, play, etc.) did not frequently occur during tests. While the ultimate implications of these gaps in testing are unclear, these results highlight the risks of live reliability testing as an inherently non-standardized process. We suggest several approaches to help address these limitations, including refining ethograms, reconsidering criteria, and supplementing live training with video. We hope this self-critique encourages others to critically examine their methods, enhance the quality of their behavioral data, and ultimately, strengthen conclusions drawn about animal behavior and welfare. Full article

Behaviour signals the internal states that relate to an individual’s welfare and its development is influenced by the early social environment that an animal experiences. Husbandry practices can alter this early social environment, for example different rearing conditions (e.g., foster rearing by a surrogate parent of another species). Widespread implementation of altered rearing can lack empirical support and non-parent-reared animals may experience poorer welfare resulting from maternal deprivation. An opportunity presented itself to measure the effect of foster-rearing on Chilean flamingo behaviour and social preferences at WWT Slimbridge Wetland Centre and compare findings to parent-reared conspecifics in the same time period. Data were collected from April to July 2019 at three timepoints during each observation day. Binomial generalized linear mixed models were used to assess the relationship between focal chicks’ rearing background with behaviour, zone usage, and flock position whilst accounting for climatic factors and visitor numbers. The development of social preferences was assessed using social network analysis. Our results showed limited impacts on flamingo behavioural development due to foster rearing. Foster-reared chicks spent less time feeding, were more likely to occupy the nesting area of the enclosure, and had fewer significant preferred associations than parent-reared chicks, but preferred social bonds were as equally strong and durable for both foster-reared and parent-reared chicks. Our results have important welfare implications for the use of foster-rearing in captive environments; altered early social rearing environments through cross-fostering in Chilean flamingos is associated with limited differences in behavioural and social development. Full article

Environmental enrichment is widely used to improve the quality of life of animals under human care. To successfully implement enrichment programs, it is important to evaluate their effect in different enclosure types since housing conditions may change depending on external factors, such as husbandry, management, or seasonal variation. This study investigates how ring-tailed lemur (Lemur catta) behaviour changes with the availability of enrichment items and the type of enclosure the animals are housed in. Through observations, we compared the behaviour of the lemurs in an indoor and outdoor enclosure, both without and with enrichment items. Although we observed enrichment effects, we found that enclosure type had a bigger effect on the lemurs’ behaviour. Additionally, behavioural changes induced by enrichment items differed between indoor and outdoor enclosures. These results indicate that the effectiveness of enrichment items may depend on the enclosure in which they are provided and consequently suggest that the impact of these programs should not be generalised over enclosure types. This highlights that the evaluation of environmental enrichment programs remains important when optimising zoo animal welfare. Full article

Locating a vocalizing animal can be useful in many fields of bioacoustics and behavioral research, and is often done in the wild, covering large areas. In zoos, however, the application of this method becomes particularly difficult, because, on the one hand, the animals are in a relatively small area and, on the other hand, reverberant environments and background noise complicate the analysis. Nevertheless, by localizing and analyzing animal sounds, valuable information on physiological state, sex, subspecies, reproductive state, social status, and animal welfare can be gathered. Therefore, we developed a sound localization software that is able to estimate the position of a vocalizing animal precisely, making it possible to assign the vocalization to the corresponding individual, even under difficult conditions. In this study, the accuracy and reliability of the software is tested under various conditions. Different vocalizations were played back through a loudspeaker and recorded with several microphones to verify the accuracy. In addition, tests were carried out under real conditions using the example of the giant otter enclosure at Dortmund Zoo, Germany. The results show that the software can estimate the correct position of a sound source with a high accuracy (median of the deviation 0.234 m). Consequently, this software could make an important contribution to basic research via position determination and the associated differentiation of individuals, and could be relevant in a long-term application for monitoring animal welfare in zoos. Full article

Prolonged and repetitive COVID-19 facility closures have led to an abrupt cessation of visitors within UK and Irish zoos for variable periods since March 2020. This study sought to increase understanding of the impact of closures and reopenings on animal behaviour, thereby broadening understanding of whether zoo animals habituate to visitors. Data were collected from June to August 2020 at two UK facilities on eight species (n = 1 Chinese goral, n = 2 Grevy’s zebra, n = 11 swamp wallaby, n = 2 Rothschild’s giraffe, n = 2 nyala, n = 4 Chapman’s zebra, n = 2 snow leopard and n = 3 Amur leopard). Behaviour change and enclosure use was variable across species but most changes were non-significant. Grevy’s zebra engaged in more comfort behaviour during closure periods than post-closure (p < 0.05). Chinese goral engaged in more environmental interactions during closure periods (p < 0.05). Grevy’s zebra spent longer than would be expected by chance closest to public viewing areas during closure periods (p < 0.008). These results suggest variable impacts of covid-19 closures and reopenings, mirroring human-animal interaction literature. We highlight the potential for some species to take longer to re-habituate to the presence of zoo visitors. As facility closures/reopenings are ongoing, we advocate a longitudinal monitoring approach. Furthermore, we recommend incorporation of physical and physiological measures of welfare where possible, alongside behavioural responses, to enable a holistic approach to answering fundamental questions on whether zoo animals habituate to visitors. Full article