Sun Orientation of Fish at Different Latitudes

The environmental cues which could be of importance for long distance orientation in fish have recently become the subject of intensified investigation [1]. Fish can use the sun's position asdirectional reference and remain oriented into a compass direction through-out the day by making allowance for the sun's daily movement [2]. Evidence for this so-called sun-compass behavior esulted from experiments in which immature sunfish were trained to swim into a certain angle to the sun at a specific time of day. The angle of the oriented movement of the fish to the sun's position changed throughout the day so that they compensated for the azimuth movement of the sun: In this orienta-tion to the sun every angle recurs at 24-hour intervals. Sunrise and sunset are the significant cues whic