seismic squid

CarlS

O. vulgaris
Registered
#5
That's disturbing news, though it certainly makes sense that the shock waves would have an adverse effect. The question now is, will the people doing the blasting stop?

As far as the emoticon is concerned, how about this?


--Carl
 

Steve O'Shea

Colossal Squid
Supporter
#8
It's a tough one C; it is quite possible, similar in fact to how the sperm whale might immobilise prey in order to catch it.

I must admit that the only cephalopod remains I have seen (from the stomach contents of sperm whales) are beaks. But from what I've read, and based on the photographs that I've seen, large squid as a rule seem to be intact, or effectively so (some without the head, others without the mantle, but without tooth marks on either end). The danger is that people are less likely to take photographs of mushed up squid from the stomachs of these things than they are to take pics of entire and very large squid, so that we get a rather biased picture of what is going on (large/intact squid might not be the norm).

The sonar/underwater detonation could have a similar effect on squid as a whale's sound emision (we call this a 'sonar canon' in the latest AFO episode. In fact we dwell on this in the latest AFO (the colossal squid/whale episode), and we also talk about frequency and squid reaction to certain frequency (ranging from attraction to alert, panic and death)). Although there's a lot of hype in the programme, there's a lot of science in there as well .... We also put a real squid in the jaws of a mechanical sperm whale and try and eat it without putting a tooth mark in it .... and it can't be done (so the whale couldn't be using the 'jaw' as a feeding aparatus; it is possibly immobilising/killing prey with the 'sonar canon' and then slurping it up. Recent evidence points to the whale actually consuming spent, dead or dying squid).

We do know that sonar has a serious effect on whales, and has been identified in a number of instances as the cause of strandings. The same could also apply to squid.

I'll keep an open mind on this NS article; he could be on to something.
 

amniote

Pygmy Octopus
Registered
#9
IMHO it seems highly unlikely that the sonar blast on its own could cause significant organ damage - unless the poor wee beastie was investigating the air cannon at the time! As evidence, I cite the use of high volume, low frequency sound transmitted through water in order to destroy kidney stones without causing significant damage to the surrounding tissue. The machine is called a lithotripter I believe.

Perhaps they were disgorged from the stomachs of terrified sperm whales? ;)
 

Steve O'Shea

Colossal Squid
Supporter
#10
There is a way to test this ....

If the whale is using a sonar cannon to immobilise squid prey, then the anatomy of squid recovered from the stomach contents should be damaged in a similar way.
 

TPOTH

Vampyroteuthis
Registered
#11
Steve O'Shea said:
There is a way to test this ....

If the whale is using a sonar cannon to immobilise squid prey, then the anatomy of squid recovered from the stomach contents should be damaged in a similar way.
But if the whale's sonar cannon simply daze and confuse the squid long enough to be caught/gulped by somehow disturbing statocysts then we might not see any damage.

Perhaps another way would be to submit squids to a range of frequencies... I hear we have some next door :twisted:

*saunters out...grabbing sonar cannon*

TPOTH
 

legendarycroc

O. bimaculoides
Registered
#14
thats what i thought...but isnt the sonar sound? hows it suppose to hurt the squid. According to my AUZie penpal the whale has soundwaves of up to 223Db? WOuldnt that be louder than the blue and fin whale?Why isnt it writen anywhere, shoudnt it be the loudest animal..?
 

monty

Colossal Squid
Staff member
Supporter
#15
Sperm Whale Sonar Cannon

I've thought this was an interesting theory since I read about it in Richard Ellis' book. I think there is a huge already-collected data set that could be helpful in confirming or denying it: the US (and presumably other countries') navy has done extensive research in classifying sounds picked up by passive sonar systems. If sperm whales are producing sounds for hunting, it seems inevitable that they've detected and cataloged them. I expect if one could find the right people to ask in the navy, they'd be happy to make a positive contribution to cetacean science; if they get good press from that, it might make them more responsive about other issues in how their operations impact marine animals... (I've noticed that some environmental groups seem intent on villifying the navy, while most navy people I've talked to actually like marine life and are enthusiastic about opportunities to help researchers)
 

CarlS

O. vulgaris
Registered
#17
I'm not a biologist by any stretch of the imagination, but I've worked with sound pressure levels (SPLs) in an engineering capacity, and 223 dB is awfully loud. :shock:

Here's a table I found listing comparative sound levels that includes a blue whale from this NOAA website.:

NOAA said:
Amplitude of Example Sounds In Air (dB re 20µPa @ 1m)
and In Water (dB re 1µPa @ 1m)

threshold of hearing 0 dB --
whisper at 1 meter 20 dB --
normal conversation 60 dB --
painful to human ear 130 dB --
jet engine 140 dB --
blue whale -- 165 dB (in water)
earthquake -- 210 dB (in water)
supertanker 164 dB (in air) 190 dB (in water)

*note - sounds are in air unless otherwise noted

Every additional 3 dB represents a doubling of power of acoustic energy.
223 - 165 = 58 dB which represents 19.3 doublings of acoustic power. :shock:

The sperm whale is a big animal which can probably make some very loud sounds if it wants to, but to reach 223 dB, it would have to be 58 dB louder than a blue whale.


Here's another table from the Ocean Future Society

Cousteau said:
Noise Source Noise Source Levels

Lightening Strike on Water Surface 260 dB (max)
Seafloor Volcanic Eruption 255+ dB (max)
Fin Whale 160-186 dB
Humpback Whale 175-190 dB
Bowhead Whale 158-189 dB
Blue Whale 188 dB (max)
Southern Right Whale 172-187 dB
Gray Whale 185 dB (max)
Source: SURTASS LFA Environmental Impact Statement
This gives a higher SPL for the blue whale, but the highest level for all the whales listed is 190 dB, which is still 33 dB (11 power doublings) below the 223 dB level in question.

--Carl - saying 223 dB is awfully loud :?
 

legendarycroc

O. bimaculoides
Registered
#18
ya i had trouble believing what i heard, but i trusted him, anyone here watched whale vs squid? HOw loud did they say the whale was?

P.s. ive read the fin and blue whales both reach a max. of 190Db, therefore the loudest of animals...
 

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