Eleven hinds and their calves were observed on a deer farm in order to study their vocal communication. Red deer calves are ‘hiders’, and therefore it was believed that they would need to recognize their mother's voice, but the hinds would not need to recognize the voice of their offspring. The following predictions were tested. First, the calf can recognize its mother by voice. Second, the hind's ability to recognize her calf by voice is less pronounced. The study had two parts. Part I was focused on spontaneous behaviour of the animals. Part II involved experiments with audio recordings. It was observed that the hinds vocalized more frequently than the calves, and it appeared that the vocalization served primarily a contact function. The calves seemed to recognize their mothers' voice better than vice versa. For the hinds, vision was more important than hearing. Thus, the predictions were confirmed.