SFBR) chimpanzee colony is a conventionally housed production and research population. The present population is 203 chimpanzees, consisting of 87 males and 116 females. Fifty-four apes were born between 1985 and 1989, 56 from 1980 to 1985,49 from 1975 to 1980,24 from 1965 to 1975, and 20 from 1954 to 1965. Twenty-five apes were added to the colony from outside sources over the last 10 years. The average yearly mortality for the past 8 years was 2.4%. The primary causes of death since 1982 were heart disease (6), trauma (5), and respiratory disease (4). The heart lesions included myocarditis, necrosis, fibrosis, and mineralization. The respiratory disease deaths were due to Streptococcus pneumoniae and Klebsiella pneumoniae. The traumatic deaths were primarily in young chimpanzees and were caused by adults. Since 1976,20 stillbirths occurred and were not included in the total deaths. There were two cases of placenta previa and one of abruptio placentae. Clinical conditions not leading to death included respiratory disease, parasitism, alopecia, diarrhea, maternal rejection, and trauma. The most significant commonly isolated bacteria were Staphylococcus, Streptococcus, Haemophilus, Klebsiella, Citrobacter, and Campylobacter. The most common intestinal parasites were Balantidium, Entamoeba, Chilomastix, Iodamoeba, Giardia, Trichuris, Enterobius, and Strongyloides. The colony pathology is sketchy from 1967 to 1981, but the main causes of death during this period were probably pneumonia and intestinal disease.