All six species of sea turtles found in U.S. waters are listed as endangered or threatened, but the exact population sizes of these species are unknown due to a lack of key information regarding birth and survival rates. This report reviews current methods for assessing sea turtle populations and finds that although counts of sea turtles are essential, they are not sufficient for development of successful management and conservation plans. Additional information on sea turtle biology, such as survival rates and breeding patterns, will be needed to predict and understand changes in sea turtle populations.