Fifty-six mature Nigerian indigenous chickens (8 cocks and 48 hens) were used for this study At the first 4 weeks birds in pens 2, 4, 6, 8 (enriched group, EN) were provided with enrichment materials (three-tiered perch and a sandbath) in addition to a nest box, feeder and drinkers which were also present in pens 1, 3, 5, 7 (unenriched group, UN). From week 5-8, the enrichment materials provided to birds in pen 2 and 4 were removed but retained in pens 6 and 8. Also, birds housed in pens 1 and 3 were provided with enrichment materials (as above) but not to birds in pens 5 and 7. The behaviour of the birds were recorded three consecutive days in each week at dusk (18:00- 19:00h), early night (ENight: 19:00 -21:00h) and early morning (EMorn: 04:30-05:30h). Blood was sampled fortnightly from the birds to measure their level of stress (blood glucose and heterophil/lymphocyte ratio). At dusk, EN birds roosted on the perch earlier in readiness for sleep. During ENight, enrichment had effect on sleeping position with EN birds sleeping on the perch and UN birds sleeping on the nest box or on the floor. However, at the EMorn, enrichment had effect on sleeping position (same as ENight), neck position (increased neck stretching) and sleep direction (increase in face backward). Transition from one environmental condition to the other was associated with only behavioural changes but not on the level of stress experienced by the birds.