In the fascinating realm of animal behavior, the dichotomy between stereotypy and adaptive actions presents an intricate puzzle for scientists. Stereotypies, defined as repetitive, invariant behaviors often devoid of apparent purpose, have been observed widely across various species, from captive mammals to domesticated pets. Their prevalence raises critical questions about their implications for animal welfare and psychological well-being. Recent research by Hildebrand and Zaleśny has aimed to elucidate the tenuous relationship between these abnormal behaviors and cortisol levels, a hormone closely associated with stress responses in animals.
As the research delves deeper into this topic, it uncovers the complexities embedded within stereotypies. Common examples include pacing in captive elephants, feather-plucking in birds, and the rocking seen in some primate species. Despite the overtly maladaptive nature of these actions, it is essential to consider the underlying factors that may contribute to their occurrence. Environmental stressors, lack of enrichment, and social isolation typically exacerbate the prevalence of these behaviors, indicating that they are often symptomatic of more profound welfare issues experienced by the animals.
Exploring cortisol levels provides crucial insight into the physiological impacts of stereotypies. Cortisol, often referred to as the “stress hormone,” is released in response to stressful events, and its chronic elevation can result in adverse health outcomes, including compromised immune function and increased susceptibility to disease. Therefore, examining the relationship between cortisol and stereotypic behavior opens a window into understanding the broader implications of these maladaptive actions on the well-being of animals.
The review conducted by Hildebrand and Zaleśny presents evidence that higher cortisol levels frequently correlate with the display of stereotypic behaviors. This suggests an intriguing, albeit concerning, cycle where stress leads to stereotypies, which in turn may exacerbate stress levels due to social or environmental factors. Their findings indicate that continuous exposure to stressors can result in a state of hyperarousal, potentially linking stereotypic behavior to escalating cortisol levels, creating a vicious cycle that can become increasingly difficult to break.
However, not all stereotypies are created equal, nor do they all have the same implications for welfare. In some contexts, certain types of stereotypic behaviors may serve as coping mechanisms for animals, providing them with a sense of predictability and control in otherwise unpredictable or stressful conditions. This brings to light a vital consideration: do some stereotypies serve a beneficial purpose in alleviating stress, or are they primarily detrimental to the animal’s welfare?
The researchers argue that understanding the context in which these behaviors occur is paramount. Most importantly, the interpretation of stereotypies as mere maladaptive behaviors might overlook their potential role in stress management. For instance, when animals exhibit stereotypies in response to barren environments, these repetitive actions might fulfill a psychological need for stimulation or predictability. In such cases, modifying the environment to allow for more natural behaviors might reduce stress and, consequently, the prevalence of stereotypies.
The implications of this research extend beyond academic inquiry and touch on ethical considerations in animal husbandry practices. For those who care for animals in zoos, research facilities, or domestic settings, recognizing the signs of stress and understanding the motivations behind stereotypic behaviors are crucial steps in improving animal welfare. Practical solutions may include designing enriched environments or implementing social structures that align more closely with the species’ natural behaviors and social systems.
Importantly, the examination of cortisol levels provides a measurable biomarker for assessing animal stress and welfare. By monitoring these levels in conjunction with observations of behavior, researchers and caretakers can better discern which environmental variables are contributing to heightened stress and, subsequently, the increase in stereotypies. The findings present a call to action for those in the field; a need for holistic approaches that consider both behavior and physiological metrics when evaluating animal welfare.
By challenging preconceived notions around stereotypies, Hildebrand and Zaleśny pioneer a path toward enhanced understanding. As they unravel the complexities of animal behavior and welfare, they underscore the importance of interdisciplinary approaches that integrate behavioral science, physiology, and animal care practices. Their work encourages further research into the nuances of animal behavior and highlights the multifaceted nature of stereotypies within the greater context of animal welfare.
This exploration not only deepens our understanding of abnormal behaviors but also pushes for more humane practices within animal care environments. As we reckon with the realization that some stereotypies may be more beneficial than previously thought, it becomes imperative to reassess how we approach animal welfare and the environments in which captive animals are kept.
In summary, this groundbreaking review offers significant insights into the intricate relationship between cortisol levels and stereotypic behaviors in animals. It shines a light on the complexities of animal welfare, encouraging a shift toward more nuanced and compassionate perspectives on behaviors that were once hastily categorized as simply abnormal. As we expand our understanding, we open the door to improving the quality of life for countless animals worldwide.
Subject of Research: Relationship between cortisol levels and stereotypic behaviors in animals.
Article Title: Do stereotypies help or harm? Exploring the link between cortisol level and abnormal behaviours in animals: a review.
Article References:
Hildebrand, W.H., Zaleśny, G. Do stereotypies help or harm? Exploring the link between cortisol level and abnormal behaviours in animals: a review.
Front Zool 22, 20 (2025). https://doi.org/10.1186/s12983-025-00576-0
Image Credits: AI Generated
DOI: https://doi.org/10.1186/s12983-025-00576-0
Keywords: Stereotypies, cortisol, stress, animal behavior, animal welfare, psychological well-being, repetitive behaviors, environmental enrichment.
Tags: animal welfarecortisol levels in stressed animalsenrichment needs for domesticated animalsenvironmental stressors affecting animal behaviorimpact of stereotypies on animalsmaladaptive behaviors in petspsychological well-being in captive animalsrepetitive behaviors in wildliferesearch on animal behaviorsocial isolation in animal populationsstress responses in various specieswelfare implications of abnormal animal actions



