Reproductive Management Plan of Toledo Zoo Lowland Gorillas Over the Past 25 Years

The breeding program for gorillas at the Toledo Zoo up to 1983 had resulted in five pregnancies over an 18 year period. In 1983, we began a multifaceted effort designed to improve reproduction through behavioral, physical, dietary, and physiological evaluations. Measurement of steroidal hormones in urine proved useful in monitoring ovarian activity and, in one […]

Perspectives – Minimizing Observer Bias in Behavioral Studies: A Review and Recommendations

Since the 1970s, texts on research methods in animal behavior advocate that researchers minimize potential observer bias in their studies. One way to minimize possible bias is to record or score behavioral data blind to treatment, group, or individual. Another way to reduce bias is for researchers to analyze subsets or entire sets of data […]