In this study the navigational competency of Physarum polycephalum in variously sized environments was tested. Petri dishes of 6 ,10, and 14 cm were tested with U-shaped traps and oats placed on the closed end of traps. Results were analyzed based on time taken to begin moving; time taken to reach goal since start of experiment and time taken to reach goal since start of moving. Results showed that the 10 cm dish tests seemed to be the easiest for Physarum to navigate, which opposed the presumption that the smaller dish would be the easiest. This could be due to other unforeseen factors such as slight environmental changes in the laboratory settings.