Infant development in a captive-bred aye-aye (Daubentonia madagascariensis) over the first year of life

Abstract

An adult wild-caught female aye-aye (Daubentonia madagascariensis) and her captive-bred offspring were studied for 2 weeks pre partum and 52 weeks post partum. Data on activity, substrate use, approach-leave interactions and social interactions were recorded in 30-min samples. Observations on the mother were started 10 days pre partum, and 2 h of data were collected on each of 9 days up to birth. Observations in each week were split evenly over 5 days and between two 4-hour blocks of time during the aye-ayes' active (dark) period. Ten h of data were collected in weeks 1-24, 5 h in weeks 25-40 and 2.5 h in weeks 40-52. Infant development and patterns of interaction with the mother, in terms of responsibility for proximity, grooming, play and food-sharing behaviour are described. Comparison with other prosimians indicates that aye-aye infants develop relatively slowly. The infant aye-aye first emerged from the nestbox in week 8, tried solid food in week 14, but did not feed herself regularly until week 20, and was still food begging and attempting to suckle at a year of age. This long period of dependence is inferred to be related to the aye-aye's unique percussive and extractive foraging techniques, which require fine motor coordination and skill, and which take time and practice to develop proficiency.