This report presents the results of an investigation of the potential effects of underwater noise from petroleum industry activities on the behavior of feeding humpback whales (Megaptera novaeangliae). The objective of the study was to determine the nature and degree of any observed behavioral response to controlled sound exposure levels from industrial noise sources. The noise sources used were a single 100 cu. in. air gun and playback of sounds from selected petroleum industry activities. The playback sounds were obtained from tape recordings of drillship, drilling platform, production platform, semi-submersible drilling rig, and helicopter overflight noise. The work was performed in Frederick Sound and Stephens Passage in southeast Alaska during August 18-29, 1984.