A debate. Can marine animals hear your drone??

[Simmo]

Hey you!
I'm having a debate, elsewhere, exactly as the title...
Can anyone post any educated enlightenment?

I posted this....

Ongoing studies say no evidence noise from drones disrupts behaviour

Scientific research on the impact of drones and their noise on marine mammals is underway, according to the Department of Biodiversity, Conservation and Attractions.

The department said results from studies in 2007, 2010, 2015 and 2016 indicated that there was no evidence of behavioural disruptions in marine mammals exposed to noise caused by low flying drones.

One of those studies was Noise Levels of Multi-Rotor Unmanned Aerial Vehicles with Implications for Potential Under water Impact son Marine Mammals by Fredrik Christiansen, LaiaRojano-Doñate, Peter T.Madsen, and LarsBejder.

“So far no behavioural reactions toward unmanned aerial vehicles (UAVs) have been recorded for marine mammals under water,” it said.

“Hence, the acoustic effect of UAVs on marine mammals in water, even when flying less than 10m above the study animals, is likely to be absent or very small, and far less than that of conventional aircrafts.”

My 'opponent' posted..

Yeah prop noise isnt bad but the ultrasonic sensors on the phantom/mavic etc for height position **** dolphins at the very least from what I've seen

Then I said....

ultrasonically, I think that an above water transmission, would bounce a lot easier off a water surface, I would hazard a guess, that low power ultrasonics couldn't be heard under water from a low height. (Absolutely happy to be proved incorrect tho!)

What do the Brains trust think??

 

[choo choo]

Hey you!
I'm having a debate, elsewhere, exactly as the title...
Can anyone post any educated enlightenment?

I posted this....

Ongoing studies say no evidence noise from drones disrupts behaviour

Scientific research on the impact of drones and their noise on marine mammals is underway, according to the Department of Biodiversity, Conservation and Attractions.

The department said results from studies in 2007, 2010, 2015 and 2016 indicated that there was no evidence of behavioural disruptions in marine mammals exposed to noise caused by low flying drones.

One of those studies was Noise Levels of Multi-Rotor Unmanned Aerial Vehicles with Implications for Potential Under water Impact son Marine Mammals by Fredrik Christiansen, LaiaRojano-Doñate, Peter T.Madsen, and LarsBejder.

“So far no behavioural reactions toward unmanned aerial vehicles (UAVs) have been recorded for marine mammals under water,” it said.

“Hence, the acoustic effect of UAVs on marine mammals in water, even when flying less than 10m above the study animals, is likely to be absent or very small, and far less than that of conventional aircrafts.”

My 'opponent' posted..

Yeah prop noise isnt bad but the ultrasonic sensors on the phantom/mavic etc for height position **** dolphins at the very least from what I've seen

Then I said....

ultrasonically, I think that an above water transmission, would bounce a lot easier off a water surface, I would hazard a guess, that low power ultrasonics couldn't be heard under water from a low height. (Absolutely happy to be proved incorrect tho!)

What do the Brains trust think??

Hmm. Firstly. Ultrasound is merely sound above human hearing, sound is merely energy in a certain frequency, I doubt very much if the sensors produce enough power to effect, let alone be detected by marine mammals or animals. If they did produce a large enough amount of power, you’d need a heck of a bigger battery just to power the sensors, let alone fly.
What frequency do our sensors emit ultrasound?
Is it on the same frequency and therefore detectable to marine animals?
Sound travels further through water than air, would the small amount of energy being emitted by the sensors be absorbed/dissipated in the air as a tiny amount of heat. After all, energy cannot be destroyed, only changed into another form.
And finally ....

Consider that bats emit ultrasound in the form of clicks to locate their prey, using echo location. It would be interesting to see if our sensors effect bats, which often fly during the ‘golden hour’ when the wind drops just before dusk. I would think that there’d be more chance of disturbing bats than flipper and his pals.
A right can of worms we’ve opened here lol

 

[FL1H1]

Water will reflect sound - its very difficult, virtually impossible actually, to hear events on the surface underwater. Underwater, sound travels much faster and further - can't remember the speed, 3 times? Or ten times faster? But it travels further and faster. Sea life will not be affected by drones - birds will, especially the smaller ones which is one reason why they might attack drones. Dogs might be able to hear drones better too, among no doubt some other land animals with sensitive hearing.

 

[TrisMavic]

Water will reflect sound - its very difficult, virtually impossible actually, to hear events on the surface underwater. Underwater, sound travels much faster and further - can't remember the speed, 3 times? Or ten times faster? But it travels further and faster. Sea life will not be affected by drones - birds will, especially the smaller ones which is one reason why they might attack drones. Dogs might be able to hear drones better too, among no doubt some other land animals with sensitive hearing.

Approx 1500M/S in water 340M/S in air. This varies with depth salidity etc but approx 4 times faster in water, and very difficult as a result to ascertain direction.

 

[TrisMavic]

based on a wildlife documentary I saw recently fish detected birds and lept out of the water to grab them mid air. Not sure if its just eyesight or if they detect the birds from vibrations/sound?

Blue Planet 2: Giant fish leaps from sea and catches bird | Daily Mail Online

 

[Mossiback]

Just tell your opponent that you turn off your downward sensors when you fly over water.

 

[macoman]

More noise produce giant transatlantic ship that cross around the globe and you will tell me that a toy grade drone produce sound underwater? What a joke.

 

[TotemLake]

>>>>dolphins at the very least from what I've seen

Mammalian marine animals break the surface of the water thus can be capable of hearing ultrasonic sounds. The Mavic Pro will detect surfaces up to 50 feet away. The water makes it difficult because of the reflection the motion of the water provides, scattering the signal. So detection may be slightly lower than 50 feet making the noise to the animals a little louder to them. We do know their hearing is sensitive in the water but the question, I think, remains how sensitive is it out of the water. I'd say remain sensitive to their hearing and maintain a respectful distance.

 

[Simmo]

So the general concensus is, nup, mammals under water, shouldn't hear ultrasonic waves from above??
But if they break the surface, they could hear it??

 

[Cslucas34]

As a former navy submariner, I can without a doubt 100 percent tell you that no, the animals are NOT hearing the drone underwater. The frequency associated with the ultrasonic sensors makes it even more difficult to transmit in water as higher frequency signals will dissipate and disperse much easier than low frequency signals and wouldn’t cross the air / water barrier.

 

[Tiny]

I have some video of dolfins. I followed them along the beach about 50 feet from shore. when I got down to about 50 feet over the water they split. Could have been coincidence, but it really seemed like the mavic platinum scared them off.

 

[neggy]

The NOAA thinks Drones and Right Whales do not mix.

To protect right whales, NOAA Fisheries has regulations that prohibit approaching or remaining within 500 yards (1,500 feet) of a right whale—500 yards is the length of about four football fields. These regulations apply to vessels and aircraft (including drones), and to people using other watercraft such as surfboards, kayaks, and jet-skis.

Any vessel within 500 yards of a right whale must depart immediately at a safe, slow speed.

 

[Stevezphoto]

I mean ... Are we doing studies to determine if boat noises affect negatively affect marine life?

How about studies about the continued dumping of an insane amount of trash and how that affects marine health?

There are so many environmental obstacles to overcome in the upcoming years, I can't see drones near the shorelines being one of the top priorities to focus energy on.

 

[beachcombing]

I mean ... Are we doing studies to determine if boat noises affect negatively affect marine life?
....

Yes, actually. They are studying that.