Behavioural responses of cockroaches Periplaneta americana L. to short and long wavelength light in a wind tunnel

The behavioural responses of the American cockroach Periplaneta americana to short-wavelength and long-wavelength light were studied in a wind tunnel. Initial directional movement towards the light source was observed in response to both stimuli, but the latency in response to green light was significantly shorter. The cockroaches moving towards the UV light often returned to the less illuminated starting point, while this behaviour was not typical under green light. UV light often initiated masking, the behavior characteristic of the inactive, diurnal phase of the 24-hour cycle.