As you explore, the center dot of the scanner might flash orange. This page explains the meaning of the flashing orange dot.

Explanation of Flashing Orange Dot

If the center dot of your scanner is flashing orange, it means that you are near a creature that is giving off strange biometric signs. Swim around the area until the dot gives a rapid double flash, then scan all the creatures around you. If you found the creatures giving off strange biometric signs, there will be an orange dot above your creature list. Scroll through the creatures list to find the one that has an orange dot next to the name. For a more detailed explanation, see How Do I Find Strange Biometric Signs?