An analysis of mother-young behaviour of fallow deer during lactation period.

In the Doñana National Park (SW Spain) female fallow deer (Dama dama ) give birth during the first fortnight of June, the next breeding season starting at the beginning of October. Between these two events the most important part of lactation takes place. Daily observations were made during the summer of 1984 and 1985. The population studied was made up of fourteen mother-young pairs that we were able to recognize individually. During each sampling period a pair of mother-young was scanned. Activities were categorized as follows: feeding, walking, selfgrooming, vigilance, mother-young interactions, and social interactions. No differences were observed in the ontogeny of behaviour neither between male and female fawns nor between their mothers. However, analysing individual differences there appeared a variation between mothers in relation to the rate of interactions towards their fawns, which was in positive correlation with the fawn's weight in the case of males. Our results also suggest the possibility of higher investment in heavier female fawns. Furthermore, there is an annual variation in the maternal behaviour in relation to the availability of resources.