How environmental enrichment affects behavioral and glucocorticoid responses in captive blue-and-yellow macaws ( Ara ararauna )

The Scent Enriched Primate

Zoos worldwide play an important role in both in situ and ex situ conservation via efforts such as providing breeding programmes and reintroductions into the wild. Zoo populations are crucial as a buffer against extinction. However, a mismatch between the wild and zoo environments can lead to psychological as well as physiological health issues, such as stress, boredom, diabetes, and obesity. These problems, in turn, can impact the reproductive success of individuals. Consequently, some primate species have reduced breeding success when housed in zoos compared to their wild counterparts. To prevent the onset of behavioural, physiological, and cognitive negative effects and to continually improve the welfare of their animals, zoos widely implement different types of environmental enrichment. There are many forms enrichment can take, such as feeding, puzzles and training, but sensory enrichments, including implementing the use of scents, are currently understudied. Scent enrichments are less utilized despite multiple research studies showing that they may have positive effects on welfare for zoo-housed animal species, including non-human primates. Despite being traditionally considered to be microsmatic, various lines of evidence suggest that olfaction plays a larger role in primates than previously thought. This review therefore focuses on scent-based enrichment and the specifics of captive primates.

Glucocorticoid metabolites in an ex situ nocturnal bird, the tropical screech owl Megascops choliba: effects of sex, activity period and inter-individual variation

Glucocorticoids mediate physiological processes to obtain energy, presenting daily variation in basal levels that may be related to behavioural activity pattern. Identification of plasticity in the secretion of these hormones is essential to understand their effects on physiology and behaviour of wild birds and, therefore, their success in their natural or artificial environment. Serial endocrine evaluations are facilitated by implementing non-invasive methodologies that minimize possible effects of manipulation on the animal's physiological variables. However, non-invasive endocrine-behavioural studies in nocturnal birds, such as owls, are immature. The present work aimed to validate an enzyme immunoassay (EIA) to quantify glucocorticoid metabolites (MGC) in Megascops choliba as well as to evaluate differences in their production at the individual, sexual or daily level. We recorded the behaviour of nine owls during three continuous days to establish activity budget under captive conditions and aiming to correlate with daily MGC variation. The EIA proved to be effective in analytical assays and in pharmacological testing with synthetic ACTH, validating this immunoassay for the species. Additionally, individual differences in MGC production were confirmed in relation to the time of day, especially at 1700 and 2100, but not in relation to sex. During night hours, the owls showed greater behavioural activity, positively related to MGC values. Higher MGC concentrations were significantly related to greater expressions of active behaviours, such as maintenance, while lower MGC concentrations were recorded during moments of higher alertness and resting. The results presented show daily MGC variation to be inversed in this nocturnal species. Our findings can aid future theoretical studies of daily rhythm and evaluations of challenging and/or disturbing situations that result in changes in behaviour or hormonal cascades of these changes in ex situ populations of owls.

Quantifying Acute Behavioral Reactions of Bali Mynas (Leucopsar rothschildi) to Environmental and Progressively Challenging Enrichment

Animals use specific behaviors and skills to overcome challenges and access resources. Environmental enrichment is provided to animals in human care to both promote species-appropriate behaviors and reduce undesired behaviors. Feather pecking in birds is an undesired behavior without a clear cause. The Saint Louis Zoo houses three pairs of young Bali mynas (Leucopsar rothschildi) who pluck neck feathers from conspecifics. To reduce this behavior, animal care staff presented the birds with seven enrichment items from four categories, presenting each item twice. The enrichment included a modifiable, progressively challenging bamboo tube device at multiple levels of difficulty. While plucking was not affected by any enrichment item, we observed significant increases in locomotion and decreases in autopreening, allogrooming, and head bobbing. Leafy greens produced the greatest changes when compared to other enrichment types. Overall engagement with the progressively challenging enrichment increased with the change from the first to the second level of difficulty, and interaction with the device was highest for the third and most difficult version. These increases suggest that no habituation to the progressively challenging device occurred, while a possible neophobic effect declined with multiple uses and increased familiarity.

Responses to environmental enrichment are associated with personality characteristics in chestnut-bellied seed finches (Sporophila angolensis)

Environmental enrichment (EE) is used to promote natural behaviours in captive animals and may hold promise as a form of pre-release training, a strategy for improving coping skills of translocated birds. We investigated the use of EE to enhance foraging and vigilance behaviours of captive Sporophila angolensis, which may be related to post-release survival. We also evaluated whether consistent individual behavioural differences affected birds' responses to EE. We submitted 19 captive seed-finches to three short-term challenges: tonic immobility (TI), new environment (NE) and new object (NO) tests. TI behaviour is related to fear/escape response to potential predators and novelty tests (NE and NO) assess neophobia, which are ecologically relevant personality traits influencing the shyness-boldness continuum. We noted a pronounced variability among the individuals' personality traits, both in their fear and escape-related responses in the TI test and along shy/bold z-scores in NE and NO tests. During a period of enrichment, birds spent more time foraging and less time in vigilance states compared with both control phases. Personality traits of the birds affected their responses to enrichment with bolder birds spending more time foraging. The EE-related decrease in vigilance was independent of the birds' personality traits. Our findings highlight interactions between personality and rearing environment that may impact post-release outcomes for translocated animals.

Bird Welfare in Zoos and Aquariums: General Insights across Industries

Animal welfare is a priority across accredited zoological institutions; however, historically, research has been prioritized for mammals. Bird-focused studies accounted for less than 10% of welfare research in zoos and aquariums over the last ten years. Due to the lack of scientific publications on bird welfare, zoo scientists and animal practitioners can look to other industries such as agriculture, laboratories, and companion animal research for insight. This qualitative review highlights findings across industries to inform animal care staff and scientists on the welfare needs of birds within zoos and aquariums. Specifically, the review includes an overview of research on different topics and a summary of key findings across nine resources that affect bird welfare. We also highlight areas where additional research is necessary. Future welfare research in zoos and aquariums should prioritize studies that consider a diversity of bird species across topics and work to identify animal-based measures with empirical evidence. Moving forward, research from other industries can help develop innovative research on bird welfare within zoos and aquariums.

Avian cognition and the implications for captive parrot welfare

Previously assumed to be unintelligent animals, many species of birds display high levels of cognition and may even possess conscious awareness. In particular, both corvids and parrots have been the focus of cognitive research including studies on problem-solving, social intelligence, and sentience. Despite their similar neural architecture and cognitive abilities, the laws regarding these two families of birds differ greatly. In the United States, it is illegal to keep corvids as pets. Parrots, however, are one of the most commonly kept pets in America, although their care in captivity remains largely unregulated. Captive parrots suffer from a number of medical and psychological issues and experience high rates of neglect and abandonment. At the same time, wild parrot populations are dwindling due both to habitat loss and capture for the pet trade. This review examines the novel findings on avian cognition and applies them to the potential ethical implications of keeping parrots in captivity. In addition, suggestions for future directions are presented, including the development of legislation to protect captive and wild parrots.

Non-Invasive Assessment of the Seasonal Stress Response to Veterinary Procedures and Transportation of Zoo-Housed Lesser Anteater (Tamandua tetradactyla)

Management procedures affect behavioural and physiological stress responses of wild mammals under human care. According to the Reactive Scope Model, normal values are presumed to exist within predictive and reactive ranges. First, stress parameters of zoo-housed adult Tamandua tetradactyla were evaluated in winter and summer (29 days each), determining the level of behaviour and/or physiological parameters needed to respond to predictable environmental changes. Secondly, the effects of veterinary procedures and transportation were studied in both seasons. Non-invasive methods were applied, assessing behaviour through videos and adrenocortical activity by faecal glucocorticoid metabolites (FGMs). Lesser anteaters exhibited seasonality (summer > winter) in some behavioural parameters, such as nocturnal activities, as well as in the activity cycle (e.g., acrophase) and FGMs. A veterinary check elicited an increase in total activity (TA), natural behaviours and repetitive locomotion and affected the activity cycle, particularly in summer. Transport produced changes in TA, nocturnal and natural activity and some variables of the activity cycle, mostly during summer. Although the effects of routine management procedures were different from each other and presumably stressful, they elicited changes only at the behavioural level, which was greater during summer. The differences observed according to non-invasive methodologies highlight the importance of a multidisciplinary approach in this context and suggest that it is unlikely that individual welfare was affected.

Casting the Net Widely for Change in Animal Welfare: The Plight of Birds in Zoos, Ex Situ Conservation, and Conservation Fieldwork

Simple Summary

Animal welfare measures have been designed to improve the health and environmental conditions of animals living under human control, for whatever reason. Welfare regulations have evolved also in line with new research insights into the cognitive, affective, and physiological domain of birds, as this paper discusses. This paper casts a critical eye on areas that Animal Welfare regulations have not reached at all, have not gone far enough, or are not regulated or supervised. It identifies the plight of birds living in captivity or being studied in the field, which either by neglect, ignorance, or design are subject to practices and procedures that may not meet basic welfare standards. The paper discusses some profound contradictions in the way we think about birds and their plight in today’s world: marked for extinction on one hand and highly admired as pets on the other; damaging fieldwork on one hand and the aims of conservation on the other. It highlights some common and distressing examples of poor welfare in birds. It also offers some solutions involving simple legislative changes and ways to eliminate some unacceptably low ethical standards in the handling and management of birds.

Abstract

This paper discusses paradoxes in our relationship to and treatment of birds in captive and conservation contexts. The paper identifies modern and new challenges that arise from declining bird numbers worldwide. Such challenges have partly changed zoos into providers of insurance populations specifically for species at risk of extinction. They have also accelerated fieldwork projects, but by using advanced technological tools and in increasing numbers, contradictorily, they may cause serious harm to the very birds studied for conservation purposes. In practice, very few avian species have any notable protection or guarantee of good treatment. The paper first deals with shortcomings of identifying problematic avian behavior in captive birds. It then brings together specific cases of field studies and captive breeding for conservation in which major welfare deficits are identified. Indeed, the paper argues that avian welfare is now an urgent task. This is not just because of declining bird numbers but because of investment in new technologies in field studies that may have introduced additional stressors and put at risk bird survival. While the paper documents a substantial number of peer-reviewed papers criticizing practices counter to modern welfare standards, they have by and large not led to changes in some practices. Some solutions are suggested that could be readily implemented and, to my knowledge, have never been considered under a welfare model before.

Should Zoo Food Be Chopped for Captive Turacos?

It is common practice for keepers in zoological collections to provide animals in their care with food that is chopped into small pieces. Anecdotally, it has been suggested that chopped food reduces wastage and reduces aggression from group-housed animals. However, there is limited empirical evidence to support these suggestions. To investigate the effects of food condition (chopped or whole food), a study was undertaken on White-cheeked Turacos (Tauraco leucotis) and Fischer’s Turacos (Tauraco fischeri) at two zoological collections in the United Kingdom. This study investigated the effect of food condition on turaco behaviour, the amount of food eaten, and also the amount of time that keepers required to prepare the diet. There was no significant impact on the amount of food eaten as a result of providing whole food. For Fischer’s Turacos, the whole-food condition significantly increased the prevalence of feeding and foraging behaviour, whilst significantly reducing preening. For White-cheeked Turacos, only feeding and foraging was affected by food condition: no other behaviours were significantly affected by chopped or whole food. Keepers on average saved 151 s per meal when preparing whole-food diets. Overall, this study suggests that changing food presentation from chopped to whole has a limited impact on food intake and behaviour. Providing whole-food items may also save valuable keeper time. Future studies should investigate the impact of feeding whole-food items to a wider range of zoo-housed species.

Decreased kynurenine pathway potentiate resilience to social defeat effect on cocaine reward

The kynurenine (KYN) pathway of tryptophan (TRP) degradation is activated by stress and inflammatory factors. It is now well established that social stress induces the activation of the immune system, with central inflammation and KYN metabolism being two of the main factors linking stress with depression. The aim of the present study was to evaluate the long-lasting changes in the KYN pathway induced by social defeat (SD) associated with the resilience or susceptibility to an increase in the conditioned rewarding effects of cocaine. Mice were exposed to repeated SD and 3 weeks later, a conditioned place preference (CPP) induced by a subthreshold dose of cocaine (1.5 mg/kg) was developed. KYN levels in plasma, cerebellum, hippocampus, striatum and limbic forebrain were studied at the end of the CPP procedure. Changes in the KYN pathway after exposure to pharmacological (oxytocin and indomethacin) and environmental interventions (environmental enrichment) were also evaluated. Our results showed that defeated susceptible (SD-S) mice had higher conditioning scores than resilient mice (SD-R). In addition, although KYN concentration was elevated in all defeated mice, SD-R mice showed smaller increases in KYN concentration in the cerebellum than SD-S mice. Oxytocin or Indomethacin treatment before SD normalized cocaine-induced CPP, although the increase in the KYN pathway was maintained. However, environmental enrichment before SD normalized cocaine-induced CPP and prevented the increase in the KYN pathway. The present study highlights the role of the KYN pathway and anti-inflammatory drugs acting on TRP metabolism as pharmacological targets to potentiate resilience to social stress effects.

Cognitive Enrichment in Practice: A Survey of Factors Affecting Its Implementation in Zoos Globally

Simple Summary

Cognitive enrichment gives animals the opportunity to challenge themselves and control aspects of their environment through problem solving. Despite the known benefits of giving captive animals cognitive enrichment, not much is known about how it is used in zoos. This survey found that staff within zoos think that cognitive enrichment is very important for the welfare of animals. However, its use is not widespread. While some animal groups like carnivores commonly receive cognitive enrichment, animals like fish and reptiles are overlooked. Time and financial support were found to be common factors that had a high impact on the use of cognitive enrichment, while zookeeper interest was said to be important for its success. Findings suggest that animal keepers, who are most often involved in enrichment programs, need to be better supported to deliver cognitive enrichment. Enrichment programs need to be prioritized with the creation of job roles specifically for enrichment or increased time and training given to keepers to carry out these duties.

Abstract

Information on the practical use of cognitive enrichment in zoos is scarce. This survey aimed to identify where cognitive enrichment is being used while identifying factors that may limit its implementation and success. Distributed in eight languages to increase global range, responses to this survey (n = 177) show that while agreement on what constitutes cognitive enrichment is poor, it is universally perceived as very important for animal welfare. Carnivores were the animal group most reported to receive cognitive enrichment (76.3%), while amphibians and fish the least (16.9%). All animal groups had a percentage of participants indicating animal groups in their facility were not receiving cognitive enrichment when they believe that they should (29.4–44.6%). On average, factors relating to time and finance were rated most highly in terms of effect on cognitive enrichment use, and keeper interest was the highest rated for effect on success. Results of this study indicate that cognitive enrichment is perceived as important. However, placing the responsibility of its development and implementation on animal keepers who are already time-poor may be impeding its use. A commitment to incorporating cognitive enrichment into routine husbandry, including financial support and investment into staff is needed from zoos to ensure continued improvement to captive animal welfare.

Temperament in Captivity, Environmental Enrichment, Flight Ability, and Response to Humans in an Endangered Parrot Species

Temperament assessment is useful in reintroduction programs. Reactivity to humans and flight ability are also important behavioral aspects for captive parrots candidates to reintroduction. The study aimed: a) to evaluate if behavioral responses to environmental enrichment differ as a function of temperament in captive Vinaceous-breasted Amazon parrots (Amazona vinacea) and b) to evaluate if the behavioral responses to environmental enrichment are related to flight ability and animal's reaction to human when offered food. A temperament assessment was performed and behavioral evaluations of parrots (n = 13) using an ethogram were carried out, in two phases: unenriched and enriched. Flight skill and food reward tests were also performed. Two temperament dimensions were described ("vigilance" and "risk-taking"). Parrots categorized as "vigilant" spent less time feeding on the feeder and interacting with environment. Animals with compromised flight ability spent more time preening, had lower frequency of vocalizations, tended to have fewer negative social interactions, and interacted less with the enrichment than individuals with better flight ability. Flight performance and temperament of captive parrots should be considered while planning and executing environmental enrichment techniques.

ACTH Stimulation Induced Self-Mutilation Behavior in the Golden Conure (Guaruba guarouba)

Simple Summary

Psittacidae are very susceptible to chronic stress and behavioral disorders. We report a successful physiological validation of an enzyme immunoassay for the non-invasive monitoring of adrenocortical activity and, thus, stress in the golden conure. In addition, as an incidental finding, we demonstrate a link between increased glucocorticoid levels and behavioral disorders. Our results are of great relevance for conservation projects and endocrine-behavioral studies of captive golden conures, where the stress evaluation is a fundamental part of animal welfare programs.

Abstract

Psittacidae are very susceptible to chronic stress and behavioral disorders. Information regarding the endocrinology of the golden conure is scarce, especially about adrenocortical activity. Endocrine studies using non-invasive methods are useful, because they allow longitudinal analysis with high numbers of samples without causing additional stress and are viable in the psittacidae management. The objective was to physiologically validate an enzyme immunoassay for measuring glucocorticoid metabolites (GCMs) in this species. Serial droppings were collected from 16 animals. First, one subgroup received adrenocorticotropic hormone (ACTH; Synacthen Depót^®) and the other group served as controls. This procedure was reversed afterwards. All birds presented self-mutilation approximately 6 h after the ACTH injection. This behavior disappeared after two days. Peak concentrations (on average nine times higher than baseline values) of GCMs were found 6 (4–8) h after ACTH administration; in all (but one) animals also a second peak was found 14 (10–20) h post injection. GCM levels returned to the baseline after 24 h. We physiologically validated a cortisone enzyme immunoassays to measure adrenocortical activity in the golden conure. Such non-invasive methods are important for studies, which are related to welfare, reproductive, and conservation programs. In addition, we could demonstrate a link between increased glucocorticoid levels and behavioral disorders.

Captivity stress influences the DNA damage of Pavo cristatus under environmental conditions of Faisalabad, Pakistan

The surroundings of wild and captive birds are divergent in existence. Wild birds inhabiting their natural environment have unlimited resources availability. They face variety of captivity stresses when moved from wild habitat to caged enclosures. The effect of similar captivity stresses on the DNA of birds living in cages for longer stretches of time is addressed in this study. The laboratory analysis to investigate DNA damage in Pavo cristatus was performed using single-cell gel electrophoresis (SCGE) or comet assay. Our results showed that measurable DNA damage was observed in Pavo cristatus species. Endogenous stress factors owing to long-term captivity were responsible to cause this damage. The caged conditions provided to the captive birds can be improved in order to prevent DNA impairment. Moreover, appropriate monitoring and effective management are necessary on continual basis to ensure the well-being of caged birds.

Stress in captive Blue-fronted parrots (Amazona aestiva): the animalists' tale

Understanding stress physiology is crucial for species management because high levels of stress can reduce reproduction and the individual's ability to face threats to survive. One of the most popular methods for non-invasive monitoring of animal endocrine status is the glucocorticoid (GC) metabolite measurements, which can provide important information about how animals are affected by their surrounding environment. Here, we carried out the biological validation of corticosterone enzyme immunoassays (EIAs), which together with a cortisol EIA was used to quantified the concentrations of urofaecal GC metabolites (uGCMs) in wild and captive Blue-fronted amazon parrots (Amazona aestiva). Urofaecal GC concentrations were significantly higher (P < 0.05) in free-living parrots (157.9 ± 18.5 ng cortisol/g and 61.14 ± 23.5 ng corticosterone/g dry urofaecal sample) than in those kept in captivity, which showed the comparable levels of GC metabolites independently of the management system applied. The higher uGCM levels obtained in the wild population point to an adaptive response for survival and species propagation in a more challenging environment, in comparison with captive animals. Furthermore, the lower uGCM concentrations in captive parrots may indicate an adaptive capacity of the species A. aestiva to captivity and its potential as a legal pet. The corticosterone EIA applied in this study proved to be an effective technique for the adrenocortical activity monitoring in this species. We discuss our findings considering the management and destiny given to wild-caught birds that are kept in confinement or returned to nature.

An Animal Welfare Risk Assessment Process for Zoos

There is a growing interest and need for zoos to develop and implement welfare assessment tools that are practical to use and provide meaningful results that can inform management decisions. This paper presents a process that was developed to support this type of evidence-based management in zoo animal welfare. The process is configured to facilitate institutional risk assessment, using an adapted version of the Five Domains Model for animal welfare assessment. It is designed to systematically analyse information gathered from zoo personnel in order to highlight areas of welfare risk, as well as areas that are performing well and areas requiring further investigation. A trial was conducted on three zoos over three years. Results of the trial suggest the process developed is practical and effective in identifying areas of welfare risk in a wide range of species in a zoo setting. It represents a further step towards achieving high-level animal welfare in zoos by integrating animal welfare as an institutional priority. The more zoos that employ such strategies, the greater the ability of the sector to advance the welfare of the animals in their care.