Environmental enrichment is used in zoos and aquariums to improve animal welfare through the stimulation of naturalistic behaviors and reduction of stereotypic behaviors. This study investigated the impact of new enrichment items on the behavior of a group of captive adult harbor seals. Data were collected in summer-autumn 2023 using continuous scan sampling and all behaviors one-zero recording method for 1-minute intervals (4 hours/day, 8 days). Under standard enrichment conditions, more than 90% of the seals’ behavioral budget was represented by naturalistic behaviors, with low levels of pattern group swimming, which occurred mainly before the two daily shows. Group swimming decreased and random swimming increased before the seal shows on days with new enrichment, but these differences were not statistically significant. The presence of new enrichment items led to a significant increase in exploration and a significant decrease in group swimming only during the morning periods when the new items were actually present in the enclosure (p<0.05, Kruskal Wallis test).
During these periods the seals interacted most frequently with the submersed fishfilled puzzle feeders and least frequently with the floating artificial seaweed. This study concluded that new environmental enrichment may be beneficial even for seals displaying low levels of stereotypic behaviors as it provides more behavioral choices and helps promote active naturalistic exploratory behaviors which may alleviate captivity induced stress and improve welfare.