Pelicans have lived in St James’s Park, London for 360 years, but this summer marked a historic moment as they successfully hatched their first chicks in the park’s history. This nesting event has captured public interest, offering a rare glimpse into the natural behaviors of these birds. Breeding in zoos is a complex process that requires specific environmental and social conditions. Pelicans need more than just comfort; they must respond to cues that stimulate courtship, nesting, and reproduction—behaviors that are essential to their natural life cycle. The nesting at St James’s Park highlights the role of "eustress," a term derived from the Greek prefix "eu," meaning good. Eustress refers to the positive response to a stressor, such as the natural challenges of finding a mate, raising offspring, and adapting to environmental changes. These stressors are not inherently negative; they can enhance an animal’s ability to learn and adapt. For example, the energy and attention required for raising young can lead to improved survival skills and more complex behaviors. As understanding of animal welfare deepens, it becomes clear that meaningful challenges—those that reflect an animal’s natural environment—can enhance their well-being. These challenges allow animals to make choices, solve problems, and express natural behaviors. Zoos can incorporate these elements without major changes to their facilities. Simple adjustments, such as hiding food in different locations, introducing natural materials, or altering the texture of surfaces, can encourage animals to explore and adapt. Variation is crucial. If food is always available in the same place and at the same time, animals may not engage in the problem-solving behaviors that are essential to their natural instincts. Many zoos already use enrichment techniques to stimulate natural behaviors. The next step is to ensure these challenges are meaningful and allow animals to engage with them voluntarily. The goal is not to make life harder, but to provide opportunities for animals to use their skills and make decisions, just as they would in the wild. For example, meerkats in zoos can be given the challenge of foraging for food, similar to how they do in the wild. This involves digging, exploring, and learning from more experienced group members. Zoos can recreate this by scattering food or creating environments that encourage digging and social interaction. Similarly, clownfish in aquariums benefit from a complex social structure and environment that mirrors their natural habitat, including a host anemone and a hierarchy of fish. The nesting of pelicans in St James’s Park exemplifies the importance of natural challenges. Breeding requires animals to adapt their behaviors, spend time on offspring, and respond to new demands. This process, known as "contrafreeloading," encourages animals to work for rewards, which can enhance their mental and physical well-being. However, it is important to ensure that any stressor is not prolonged, overwhelming, or unnatural. The key is to provide challenges that are biologically relevant and meaningful for each species, enhancing their lives without unnecessary hardship.