Researchers can have unintentional, yet significant effects on their study systems. We tested for the effects of an intensive tree census on seedling dynamics in a 50-ha permanent forest plot on Barro Colorado Island, Panama. At the community level, and for different shade-tolerance guilds, we found no significant differences in seedling recruitment or survival inside compared to controls outside the plot. However, among growth forms, canopy trees and lianas exhibited significantly lower seedling survival inside the plot. Results suggest that intense researcher activity impacts shortterm vegetation dynamics, but effects do not accumulate over time.