Communication is very important. communicate with sounds and body language. To growl, the croc snorts air through the throat or nostrils. The sound is like an idling outboard motor throwing a spray of water into the air from the crocodiles back. Baby crocs 'chirp' when they are ready to hatch. Crocodiles also communicate through their behaviour. Males fight to set up their territories.
Crocodiles communicate by barking and are known to have four different calls. Examples of these calls are:
The distress call, mostly used by younger animals is a high-pitched call that alerts other crocodiles in case of imminent danger or an animal being attacked.
The threat call is a hissing sound that has also been described as a coughing noise.
There is a hatching call that females make when breeding to alert the other crocodiles about the fact that she has placed eggs in her nest.
The courtship call lets other animals know that a certain animal is ready for mating and breeding.
Alligators use visual, aural, tactile, and olfactory cues. Complex body postures and movements communicate a variety of information. Both sexes give off musk. Even though they have no vocal chords, alligators hiss, grunt, cough, growl, and bellow.Bellowing choruses occur most often in spring when breeding groups congregate, but can occur at any time of year.to bellow, male noticeably inflates as he raises tail and head out of water; slowly waving tail back and forth, he puffs out throat, and with closed mouth begins to vibrate air; just before bellowing, males project an infrasonic signal at about 10 Hz through water that vibrates ground and nearby objects; the low-frequency vibrations travel great distances through both air and water to advertise caller's presence; vibrations are so strong they literally make the water "dance"
scientists report that sharks have no internal organ for making sounds.Sharks have no vocal cords and cannot communicate with other sharks in an audible
way. sharks possess a sense that is so alien to us that we can neither relate to it nor fathom what it might feel like. That sense is electroreception: an acute sensitivity to electrical fields. Sharks receive tiny electrical signals from their environment via a series of pores peppered over the head.These pores are distributed in discrete patterns, varying somewhat among elasmobranch species. In the White Shark, there is a pair of elongate clusters on top of the head above the eyes, another pair of V-shaped clusters surrounding the nostrils underneath the snout, a sausage-shaped cluster under each eye, and an oval cluster extending along each side of the chin.