Vulnerability of marine animal communication

Pollution of the world's water seriously threatens the elaborate sensory system of marine animals. Small amounts of some chemicals may not be directly poisonous, but they may have indirect, often invisible effects. They may destroy, suppress, mimic, or mask vital phenomena, garbling the messages on which aquatic life depends, confusing sea creatures, and altering their behaviour.

Pheromones are the naturally secreted chemicals by which water animals communicate up one another. Animals use these chemical messages to guide their migrations; discriminate between individuals; recognize sex and reproductive states; and sense aggressors, predators, friends and their young.