Even if they don't have vocal chords, alligators hiss, grunt, cough, growl and, most famously, bellow, the latter of which is preceded by an infrasonic signal that actually rolls along the water, causing it to vibrate or "dance." While the frequency is too low for humans to hear, it can travel great distances to reach potential mates.
This large, flightless parrot is native to New Zealand and puts on a loud performance during breeding season. Male kakapos will carve out their own Hollywood Bowl of sorts, creating an amphitheater for belting out their big love song. For the finale, the kakapo clears his throat, inflates an air sac in his chest, then releases a resonating boom that can be heard up to three miles away! He continues the ritual every night over the next four months, pumping out up to 10,000 calls.
They can make very loud howling at night. Their howling can be heard from 10 miles away. When they act in chorus, potential predators have a hard time telling just how many wolves they're actually dealing with - one or 100?
07. Howler Monkey
The howler monkey is the loudest land animal. Its calls, which some say are actually more like growls, can be heard up to three miles (five kilometers) away. The monkeys have a variety of calls, likely for communicating location, protecting territory, and guarding mates, but their vocabulary is yet unknown to humans.
They can make loud trumpet-like sound to call each other. The sound can be heard from 5 miles away, the loudest record can be heard from 20 miles away.
They are the loudest insect, the male sings loud mating call for the female. The song can reach 120 dB, 100 times louder than music discotheque. The song can be heard from 1,5 miles away.
They can make very loud sound while trying to find way home at night. Their sound can reach 137 dB, over 100 times louder than rock concert.
Herrings usually travel with over 4 million others at any given time. The noise factor comes into play with their preferred method of communication. Herrings emit gas from their bottoms to talk with each other as well as scare off predators, but it's at a frequency too low for humans to ever hear.
02. Blue Whale
The blue whale is the loudest mammal of them all, with vocalizations that reach 188 decibels. Blue whales don't have songs as complex as those of humpback whales, but their low-frequency "pulses"- some below the range of human hearing - have been recorded more than 500 miles (805 kilometers) away. Blue Whale used to be the loudest animal, until researchers found another animal louder than the blue whale.
01. Pistol Shrimp
The tiger pistol shrimp has been confirmed the loudest animal on earth. By snapping its claw into a gun-cocked position, it can snap them shut almost instantaneously. As the claws are going to hit each other, they create bubbles that collapse, and when they do, they (for a very short period of time) reach the temperature of the sun. The bubbles move at 60 miles per hour and releases sounds of up to 218 decibels. That can be heard a lot more than 500 miles away, and it beats the former loudest animal by 30 decibels, the blue whale, which can emit sounds as high as 188 decibels. This means the blue whale is louder than grenade explosion and jet takeoff/engine, but the tiger pistol shrimp can make sounds louder than volcano eruption and gunshots. It uses this as a weapon by stunning enemies because of immense sound. This animal should be #1 on this list because it is.
Source : http://junglemagazine.com