Turkey Hearing Frequencies

[CrankyTom]

Have any of you tried mating yelps?  After reading about mating yelps I read some scientific and university studies about a turkeys hearing. 

Turkey's do not hear what we hear.  What sounds great to you might sound horrible to them or they might not hear it at all! 

Volume is decibles (dB).  Tone frequency is hertz (Hz)  Decible Sound Pressure Level is (dB SPL)

The range of frequencies that a turkey with good hearing can hear is 290 Hz to 5,250 Hz.
Humans with good hearing hear a range from 20 Hz to 20,000 Hz.

Both humans and turkeys hearing frequency range declines with age.

The optimum dB SPL is15.43 Most calls are louder than that and above the pain threshold.

The best heard frequency by turkeys is 2,000 Hz

If you are using calls with a frequency higher than 5,250 Hz the turkeys cant hear it!  They may feel pressure on their ear but they won't hear it.  The only response could be a shock.  You wouldn't be calling them but you could be shocking them.

Numerous Crystal, glass, aluminum, ceramic and slate calls are higher than 5,250 Hz and above 15.43 dB SPL. Some turkeys calling can call at frequencies that turkeys cant hear.

Every call that I tested was also to loud.  Way out of the dB range.

Maybe that is a reason why you get toms gobbling and going away from you?  You aren't calling them you are shocking them!

The pic shows the range we hear and what turkeys hear.

[GobbleNut]

Interesting stuff.  Another variable in turkey calling to add to the already maddening mix!

[Ihuntoldschool]

Nice graph and info.  I don't put anything into that data though. I've called in plenty of birds with some of the M.A.D. aluminum and mouth calls that scream at frequencies up to 15,000 Hz.   

[CrankyTom]

Nice graph and info.  I don't put anything into that data though. I've called in plenty of birds with some of the M.A.D. aluminum and mouth calls that scream at frequencies up to 15,000 Hz.

Every call has a range of frequencies.  The chart below is one strike from a ceramic call that I cast with high temperature crucible ceramic.   Turkeys are curious and will come to many odd sounds just to see whats making the sound.   

[Rapscallion Vermilion]

The decibel level is a function of the distance from the call.  How far away from the calls did you measure those decibel levels?

[CrankyTom]

The decibel level is a function of the distance from the call.  How far away from the calls did you measure those decibel levels?

It was only a few feet away but I don't remember which circle I was striking or how much pressure Was applied.  Each circle, actually each area of the front and back sounds different.  Louder, softer but all are within the best frequency range heard by turkeys.  You can call as if there are multiple hens.

[CrankyTom]

Nice graph and info.  I don't put anything into that data though. I've called in plenty of birds with some of the M.A.D. aluminum and mouth calls that scream at frequencies up to 15,000 Hz.

I'm not sure that you know what 15,000 Hz sounds like.  It's not the loud screeching sound that you think it is.  It is hard to hear alone let alone along with the other frequencies that an aluminum call makes.  Go to the link below and try different frequencies and you will hear what 15,000 Hz sounds like. 

Calls in the 1,000 to 3,000 Hz range are heard the best by turkeys.

https://www.szynalski.com/tone-generator/

[Ihuntoldschool]

Turkeys are curious and will come to many odd sounds just to see whats making the sound. Maybe sometimes.

When multiple birds answer the high frequency sounding hen turkey call and each bird answers you multiple times and closes distance with gobbles getting closer and closer each time he answers your high frequency turkey call and even breaks in on your calling at times, again this pattern repeats itself on multiple gobblers until they end up at 30 yards or less and get shot, I have a slight hunch they came in looking for the hen they heard, not out of curiosity of an unknown sound. 

[Ihuntoldschool]

By the way this was researched back in the mid 1990's as well when High Frequency turkey calls really took off.  What they found was birds often responded best to sounds near 15,000 Hz. 10,000 Hz produced better responses than 5,000 Hz.  These studies helped pave the way for turkey calls reaching the higher frequencies than were previously possible.  I mentioned M.A.D as they were an industry leader as far as high frequency calls. Some of the other companies have calls that will reach the same frequencies I suspect. 

[CrankyTom]

Turkeys are curious and will come to many odd sounds just to see whats making the sound. Maybe sometimes.

When multiple birds answer the high frequency sounding hen turkey call and each bird answers you multiple times and closes distance with gobbles getting closer and closer each time he answers your high frequency turkey call and even breaks in on your calling at times, again this pattern repeats itself on multiple gobblers until they end up at 30 yards or less and get shot, I have a slight hunch they came in looking for the hen they heard, not out of curiosity of an unknown sound.

Hens normal calling frequency range is not a high pitch.  The average frequencies of all of the calls that they make are less than 5,000 Hz. 

https://www.nwtf.org/hunt/article/identify-wild-turkey-calls

This attachment is from another government funded study that was done by a university.

[CrankyTom]

By the way this was researched back in the mid 1990's as well when High Frequency turkey calls really took off.  What they found was birds often responded best to sounds near 15,000 Hz. 10,000 Hz produced better responses than 5,000 Hz.  These studies helped pave the way for turkey calls reaching the higher frequencies than were previously possible.  I mentioned M.A.D as they were an industry leader as far as high frequency calls. Some of the other companies have calls that will reach the same frequencies I suspect.

It was claimed to be researched but I suspect that it was more of a sales pitch.  The person who wrote that article was on the pro staff of turkeyhunting247, the site that wrote the article and on the pro staff of Quaker boy, the call that he pitched in the article.  What I am posting is from government funded studies.

[GobbleNut]

Dayyam!! Turkey hunting IS rocket science after all!   

[Rapscallion Vermilion]

Your first chart, comparing turkeys to humans, suggest that across their hearing range, that humans have more sensitive hearing than turkeys.  Sure hard for me to believe that.  It is also hard for me to believe turkeys do not hear gobblers drumming.

[Spitten and drummen]

May be truth to what you are saying but I know for a fact turkeys hear waaay better than people. I call soft and I call extremely loud and have been killing birds doing this over 40 years. I do not for one minute believe that a gobbler going the other way is due to vall frequency. Its hens leading them off or a strut zone they want to be in. Blow a dog whistle. We cant hear them but a dog can and thats some serious frequency. I believe a turkey hears better than a dog. In the end , I just try to sound like a hen as natural as possible. No doubt high pitched sounds cause shock gobbles but I have heard hens that had a high pitch screech in their voice. Now I have never heard a hen get as high pitched as some calls like aluminum but they must because plenty of birds are killed with them. To me thats more proof that cadence is king compared to pitch. Just my 2 cents.

[CrankyTom]

Your first chart, comparing turkeys to humans, suggest that across their hearing range, that humans have more sensitive hearing than turkeys.  Sure hard for me to believe that.  It is also hard for me to believe turkeys do not hear gobblers drumming.

None of the charts are mine they come from different studies.  Look at the screenshot in my next post