The bony fish have well-developed sense organs that are adapted to different lifestyles. The most prominent sensory organ is the eye. Fish do not have eyelids but have a well-developed eye, some fish relying on sight to catch their prey. In the murky waters of Saskatchewan, other senses play an important roll. Smell is the other important sense and most fish have two pairs of nostrils as well as chemical receptors scattered over their head and body.
Fish can detect weak currents.
This ability helps them to locate prey and avoid predators. The lateral line system, mentioned previously, detects changes in pressure and vibrations in the water. The sense of hearing is well developed in fish and the swim bladder is connected to the inner ear. Tiny stones in the inner ear transfer vibrations to sensory cells. If you wondering if fish can be 'trained', check out fish in any aquarium.