Penguins in aquariums and zoos are typically exhibited in groups of several dozen individuals, making it challenging for visitors to notice and observe them as distinct individuals. To transform this passive viewing experience into an engaging and playful activity, we developed an observation support system that enables visitors to identify individual penguins by drawing their abdominal spot patterns. Previous field studies with general aquarium visitors indicated that the system encouraged closer attention to individual penguins and stimulated social interaction. However, these findings relied mainly on qualitative behavioral observations, leaving visitors’ interaction patterns insufficiently quantified. In this study, we enhanced the system with detailed logging functionality and multilingual support, and conducted a new one-week field deployment in an aquarium. By analyzing interaction logs collected from real visitors, we reveal behavioral patterns such as repeated returns to the penguin exhibit within a single day and revisits across multiple days. These results suggest that the system may foster sustained engagement and ongoing interest in individual animals, demonstrating the potential of drawing-based interaction as an entertainment-oriented approach to enriching zoo and aquarium experiences.