This study investigated the development of suckling behavior, spatial relations, social behavior, and play behavior in 2 mother-calf dyads of bottlenose dolphins (Tursiops truncatus). Each dyad was observed 4 hours weekly throughout the calves’ 1st year. The dyads differed in calves’ sex and mothers’ parity. The dyad with the primiparous female needed more time to establish suckling and swimming routines. After the 3rd month, interactions with the mother (flipper-rub, rest together, social play, and calf watches mother) were significantly more frequent in the female calf, whereas interactions with the calves’ father (swim together, rest together, and social play) were significantly more frequent in the male calf. The calves showed high rates of object play and social play. They seemed to modify their type of play according to the opportunities they were offered. A mentally stimulating object was preferred to simpler toys. The knowledge of the details of mother-calf behavior helps to develop appropriate breeding conditions that are vital for the survival and well-being of captive dolphin calves
