Light is apparently an important factor in controlling the distribution of the herring in southern New Brunswick. They swim to the east just before sunrise and to the west just after sunset; the moon, when low in elevation, is also said to have an attractive influence. However, they are repelled by direct sunlight, the degree of repulsion depending upon the intensity of light and size of fish. During moonlight, starlight, cloudy and foggy nights, all sizes extend to the surface.