Which Animal has the Loudest ROAR?
from Wildlife Promise
Animal Planet’s ROAR campaign is highlighting NWF and other non-profits working to help animals. At the end of the campaign, Animal Planet will identify one organization for having the ‘loudest roar,’ and we think our supporters and online community can help NWF win.
You can help us achieve this by (1) reading and sharing this article, (2) visiting the ROAR page to learn more about our Adopt a Wildlife Acre program and (3) making a donation (even $1 helps).
Since we love wildlife, we decided to examine which animal has the loudest roar. Gordon Hempton, an acoustic ecologist, is the perfect person to answer this question. Gordon has been recording the sounds of nature for decades and studies the relationship between living beings and their environment through sound. Check out his full bio and enjoy his ROARing post!
The Judge (Listener)
First, I will assume the judges (listener) are people. Each species has a unique loudness contour. What sounds loudest to humans may not sound loudest to another species. People are most sensitive to the bandwidth that corresponds to the resonant frequencies of our auditory canal. So, on an average, we hear and experience ‘loud’ best between 2.5-5 kHz. We are relatively insensitive to low frequencies, so when we hear a loud roar (which is characterized by lower frequencies) this is really a lot of decibels!
The four competitors are elephants, lions, howler monkeys and meadowlarks. Let’s learn more about each contestant.
Contestant 1: African Elephant
The elephant is a strong competitor because of its size and trunk (which magnifies and projects sound).
Contestant 2: Lion
The lion intimidates other competitors because scouting reports (my experience) say it’s very loud. It has a reputation in Africa as the loudest roar.
Contestant 3: Howler Monkey
The howler monkey male is strong only when accompanied by a female to stroke his throat and work him up into a frenzy. There is a handicap given to the howler monkey (6dB) for having to leave the forest for this contest.
Contestant 4: Western Meadowlark
The western meadowlark corresponds exactly with the judge’s peak hearing sensitivity, and if their beaks act as an impedance matching transformer, may make a surgical strike on the judge’s auditory canal.
The Rules (Habitat & Distance)
We can complicate things by determining a setting (habitat) and defining a distance. Each habitat has a different set of acoustics and will emphasize some frequencies more than others. Imagine how the listening experience would be different inside a cave with a smooth interior (louder) versus a cave filled with stalactites and a powdery floor to break up the transmission of sound (quieter). Additionally, sound becomes weaker the farther we get from it, at a rate of -6dB for each doubling of the distance.
Contestants will be spaced 4-6 feet apart and away from humans in an open grassy field. Each creature has a very different frequency spectrum and envelop (attack & decay) and will be judged purely on loudness. All competitors will vocalize at the same time as the judge gradually increases their distance. The winner will be determined when the judge hears only one contestant. This will be done just before sunrise when the air is still to allow sound to travel farther.
If the judge is a human, the winner would be the western meadowlark. Here’s my field recording of the western meadowlark.
Additionally, I’ve included the the spectrum analysis of the western meadowlark. This turns sound into image. Across the bottom you have elapsed time, and going up you have frequency. The red outlines the highest or loudest part of the sound. The image shows the 3 seconds of the meadowlark’s song. We see that between 1,744 and 6,000 Hz (the frequency) is the major part of the sound whereas at 2.2 seconds into the sample it dips lower, too. Consider a spectral analysis a voice print.Let’s let the same species be the judge. Elephants will judge elephants and lions will judge lions and so forth. If the judge where only those of the same species, then the winner would be the elephant. I would include a sound clip of the elephant, but humans cannot hear the sound they make, due to the low frequency. Elephants can hear another elephant trumpeting, however, farther away than any other terrestrial species. This is simply a matter of physics. They produce the most sub-sonic content that their large ears can hear (we can not).
The winner should be the African elephant!
Gordon Hempton is the Sound Tracker®, an acoustic ecologist and Emmy award–winning sound recordist. For more than 30 years he has provided professional audio services to musicians, galleries, museums, and media producers, including Microsoft, Smithsonian, National Geographic, Discovery, National Public Radio, and numerous other businesses and organizations. He has received recognition from the Charles A. Lindbergh Fund, the National Endowment for the Arts, and the Rolex Awards for Enterprise. He studied botany and plant pathology at the University of Wisconsin. His sound portraits, which record quickly vanishing natural soundscapes, have been featured in People magazine and a national PBS television documentary, Vanishing Dawn Chorus, which earned him an Emmy for Outstanding Individual Achievement. Hempton is subject of a feature film, Soundtracker and co-author of One Square Inch of Silence: One Man’s Quest to Preserve Quiet, (Free Press/Simon & Schuster, 2010). He is Founder and Vice President of The One Square Inch of Silence Foundation and Quiet Planet®. Hempton has now circled the globe three times in pursuit of nature’s music and produced more than 60 albums available on iTunes. He lectures widely on the importance of listening. He lives in Indianola, Washington, USA.