The psychological well-being of captive animals is essential from a moral point of view and because of the animal’s physical condition. It is well established that animals can be stressed being captivated, and their state depends on the conditions in which they are kept. Enrichment is one of the most effective ways to increase animals’ physical and psychological well-being (Maple & Perdue, 2013). Psychological welfare also depends on the level of an animal’s mental health. When constant stress is presented, or the animal lacks something, it can experience a strong psychological shock. In turn, it will lead to a deterioration in mental health, which can affect the physical condition. Many researchers argue that behavioral criterion is more reliable than physiological or functional one in assessing animals’ well-being (Weichbrod et al., 2017). In other words, while conducting research, one should pay more attention to the behavioral features of the animal as it is the most important factor. In addition, normal/abnormal behavior is an important factor in the psychological health level of the animal. The individual’s strange behavior should be considered a signal indicating the failure to fulfill one of the above freedoms. Abnormal and unwanted behavior of animals may be, for example, in the form of stall kicking in horses or excessive barking in dogs (Choe, 2019). Both these examples may occur when the animal tries to cope with the impossibility of engaging in free choice and expression (Choe, 2019). This behavior is a signal about insufficient animal welfare, as it is directly related to mental health. Moreover, any animal’s action that goes beyond the usual norms may be considered abnormal behavior.
Environmental enrichment is an important tool that affects the welfare of captive animals. Considering that in zoos, animals are better fed and have a safer environment, it is sometimes stressful for them. Thereby, the main goal of enrichment is to reconstruct wild nature’s conditions and patterns of behavior in animals (Nielsen, 2017). So, one of the types of enrichment is social: communication of animals with other animals. One often uses social enrichment for pack animals: wolves, lions, etc. Enrichment involves changing the environment of the zoo to provide choices or opportunities to animals not available before (Swaisgood & Shepherdson, 2005). Thus, for fast-moving animals such as monkeys, physical enrichment is important, namely moving or adding new items and locations. For monkeys, multi-tiered structures are usually made so that the animal has more unexplored territory. Nutritional enrichment is one of the most important types, as foraging is the basis of any animal’s life. It implies not only a change in the animals’ ratio but also different ways of sorting: food can be hung or hidden so that it would be more difficult to get it. It is formulated by the fact that some predatory animals like wolves, tigers, and lions can experience stress without hunting. Different forms of enrichment which were temporarily or permanently added significantly influenced animals’ welfare (Maple et al., 2020). Such a fact determines the need for enrichment and the goal to recreate the wild nature conditions as much as possible. Moreover, further research is needed in the field of various types of enrichment and their improvement. All of this is vital for captive animals, as their basic instincts are attuned to life in the wild, and the incompatibility of their instincts and environmental conditions leads to stress and poor animal welfare.
References
Choe, J. C. (2019). Encyclopedia of animal behavior. Academic Press.
Maple, T. L., & Perdue, B. M. (2013). Zoo animal welfare. Chapter 6: Environmental enrichment. Berlin: Springer.
Maple, T. L., Perdue, B. M., & Sherwen, S. (Eds.). (2020). The science and practice of captive animal welfare. Frontiers Media.
Nielsen, B. L. (2017). Olfaction in animal behaviour and welfare. Cabi.
Swaisgood, R. R. & Shepherdson, D. J. (2005). Scientific approaches to enrichment and stereotypies in zoo animals: What has been done and where should we go next? Zoo Biology, 24, 499-518.
Weichbrod, R. H., Thompson, G. A., & Norton, J. N. (Eds.). (2017). Management of animal care and use programs in research, education, and testing. Crc Press.