Use of migration stop-overs by radio-tracked whooping cranes (Grus americana) was studied in fall 1981-83 and spring 1983-84. Information on habitat use, time-activity budgets, and hazards encountered is presented for a sample of 27 individuals, including 9 radio-marked birds. Survival rate is calculated for radio-marked birds and compared with estimates for birds not radio-marked. Distribution patterns of birds for which complete stopover information is available are contrasted with distributions derived from opportunistic observations.