Whale Communication

From: Kim Marshall (kimm@oceanalliance.org)
Date: Fri Dec 13 2002 - 17:25:12 EST

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    Question:
    Hi Kimm, my name is Linde McNamara and I am a graduate student doing a paper
    on ocean noise pollution. Could you please tell in what ' whales
    communicate?(average) Thanks.

    Reply:
    Dear Linde,
    Most whales produce sounds at around 170-180 db. Of course this depends on
    species and the behavior (feeding, communicating during mating periods etc.)
    Please go to Cornell University's bioacoustic site at
    http://birds.cornell.edu/BRP/ResWhale.html for more detailed information on
    this subject.

    Also search the archives on WhaleNet for previous answered questions on this
    subject. For information regarding the issues surrounding the Navyıs
    SURTASS/LOFAR program try the National Resource Defense Councilıs website at
    http://www.nrdc.org/search/default.asp or I have attached the following:

    Remarks on SURTASS LFA by Dr. Roger Payne, President Ocean Alliance

    It is clear that the issue before us has generated a great deal of
    controversy. Controversies are made worse if clear information is ignored
    in favor of oneıs preconceptions. I think I see that in this issue. A good
    scientist not only comes up with intriguing new theories, he or she must be
    able to abandon them just as readily when faced with strong evidence to the
    contrary they must then start again looking for a new explanation and be
    prepared to embrace it with equal enthusiasm when it appears. Some of the
    claims I have seen about the threats posed by loud sounds simply ignore a
    mounting collection of evidence.

    Though my initial worry was that sounds like the ATOC and SURTASS LFA sounds
    might pose very serious threats indeed, the accumulating evidence does not
    point to that. The loudest sounds made by ATOC and SURTASS LFA are not as
    loud (in some cases not nearly as loud) as those generated by several
    sources that are already out there and working. Before I list some of them I
    want to point out that I like all of us here would like to avoid any
    increase of noise in the oceans but that it is important also to realize
    what is already out there and how much SURTASS LFA and ATOC would be adding
    to that background.

    The sounds that seem most compelling are as follows.
    1) Ships are responsible for the lionsı share of noise in the frequency
    range of whales and the SURTASS LFA. We were told that there are 75,000
    ships in the world of which 6,500 are tankers, though how many are big
    enough to be louder than the Lofar sonar I donıt know.

    2) Right whales concentrate each year off South Africa along coastlines that
    they share with passing super tankers traveling at full throttle as close to
    some of the bays as the tanker captains dare to come since close approaches
    of a few miles make a considerable saving in time and fuel burned. These
    vessels make sounds much louder than SURTASS LFA.

    3) The underwater sounds generated by earthquakes are far louder than the
    Corey Chouest at full voice. And there are thousands of seismic events
    every day many of which reach loudnesses greater than those made by Corey
    Chouest.

    4) There are an estimated 20 million lightning strikes that hit the ground
    in the US every year. We are much less than 15% of the oceanıs surface
    meaning that there are probably at least 100 million bolts hitting the ocean
    each year. All of them are incredibly much louder than the sounds the Navy
    is producing, and all of them have an extraordinarily sharp onset, and are
    presumably experienced without warning by animals nearby.

    5) The entire time a plane like the supersonic transport or war planes
    capable of supersonic flight are traveling at supersonic speeds over water a
    shock wave is continually insonifying the ocean. It is not a single
    explosive sound but a continuous roar during the entire period the speed of
    sound is being exceeded. (We experience it as an abrupt explosive sound
    because we only hear it during the moment the wave front passing us, but the
    generation off such sound and its entry into the oceans goes on
    continuously, and is much louder than SURTASS LFA signals.

    6) There are thousands of percussive sounds made by humans each day in the
    sea. They come from seismic exploration for oil, wars, dynamiting to
    dredge‹even from nuclear tests.

    7) There are places where the sounds of rockets lifting off put enormous
    sound energy into the water. E.g. Cape Canaveral, Japan, South Africa etc,
    All of these put into the sea up to thousands of times the energy of SURTASS
    LFA, and in the case of Cape Canaveral and South Africa they take place on
    land abutting prime calving habitat of right whales, the rarest species.

    8) Of course the very loudest thing a whale must face is its own voice, made
    only a meter or two, at most, from its ears. Surely whales must surely have
    good ways to deal with such sounds. But also they must have methods to deal
    with natural loud sounds like lightning or earthquakes, or whole groups of
    them would be wiped out after each such event. One of the defenses mammals
    have to avoid damage from loud sounds is by contracting a muscle attached to
    the stapes via the stapedial ligament. Tension on this muscle holds the
    stapes more rigid where it enters the cochlea, which helps to prevent damage
    from loud sounds. Darlene Ketten has pointed out that in whales the
    stapedial muscle is ³an Arnold Schwartznegger of a stapedial muscle.²

    Whales live in an incredibly noisy environment, the noisiest on earth. It
    is not realistic to believe that they do not have well evolved systems for
    dealing with very loud sounds. If we bring this whole problem onto land, we
    might find it easier to imagine what we are really dealing with. Let us
    assume that a terrible storm is going on with the wind shrieking (analogous
    to wave noise), and that we are in a truck driving out across a field in
    which several deer are grazing. As we approach closely to them we turn on a
    claxton horn. I think there is no one of us that would not expect them to
    stop feeding and scatter at once. I was on board the Corey Chouest when it
    was on a course that carried it close to a blue whale. When it came time
    for the next ³ping² the whale was very close. The ping occurred, yet there
    was no visible reaction of the whale. I felt that if ever we might have
    expected to see a reaction it was then. Yet there was no change of course,
    no change of speed. No cessation of vocalization.

    We are faced with what Maurice Ewing, discoverer of the deep sound channel,
    and instrumental in establishing the veracity of plate tectonics, called
    brutal facts--facts that go against our dearly held preconceptions. As
    Chris Clark pointed out: ³There were no obvious and consistent responses
    during exposure to LFA. Individual whales did not actively avoid the LFA
    source. Individual whales did not appear to move out of the research area
    or redistribute themselves in the are during experimental use of LFA.²

    There was, of course some indication that whales decreased their vocal
    activity during periods of LFA based on real-time estimates of the number of
    whales producing long, patterned sequences of sounds. [story of car missing
    you]

     If we are really being scientific in our judgment of what has been found
    out and not just looking for evidence that our hunch to start with is right,
    it is important to adhere to the rules of scientific theorizing. They
    include the fact that you must argue as vigorously against a theory that
    supports your initial hunch as you argue for it. When the data supports
    your theory you must doubt it as vigorously as when they oppose your theory.
    I donıt see that happening. If these scientists had played loud sounds to
    12 focal animals and they had all fled, (which they did not do, of course)
    you must argue as vehemently that it may not be representative of their
    behavior and that they are not really being disturbed. If you would not be
    willing to seriously draw that conclusion you should not be willing to
    seriously draw the conclusion that surtass Lfa is as serious a threat as we
    all feared when we first heard about it.

    The result of this and of the above points inclines me to believe that this
    whole issue will not turn out to be the big problem it seemed to me and to
    many of us here at first. What I fear I am looking at in several groups
    around me is a disingenuous use of the threat posed by SURTASS LFA because
    it is a great issue on which to raise funds for any conservation
    organization. If one realizes that his or her argument is flawed yet makes
    it anyway because it is a good way to raise funds, then that is a form of
    fraud--a means of taking advantage of the lesser knowledge of a public in
    order to get them to part with funds because they think they will be helping
    whales. The trouble is that if anything is ever found out about SURTASS LFA
    which we should be truly worried then the arguments against these
    human-generated loud noises will have been so discredited that we wonıt be
    able to reignite the issue in time to bring any relief. (Suppose that ALAR
    were to be found now to really pose the threat it was thought to pose now.)
    So much nonsense will have gone unchallenged that whales could lose the war
    later on.

    There are so many other issues that really are a threat to marine life and
    to whales, dolphins and porpoises in particular, that I feel the focus on
    this one is robbing them of help we might otherwise be offering that they
    really do need. For all of these reasons I feel that all of us who call
    ourselves whale conservationists might want to consider being honest about
    what we do to raise funds and in the meantime quietly withdraw from this
    issue for a while and adopt a wait-and-see stance using the time thus freed
    to get into the kinds of issues that really are a threat to whales: say
    pollution, destruction of habitat, and entanglement in fishing gear.

    At present I believe that feeling deeply concerned for what SURTASS LFA
    might do is pursuing vigorously a cure for which there is no disease.

    I hope this is helpful to you. Happy holidays!

    Kim

    Kim Marshall
    Executive Director
    Ocean Alliance (Whale Conservation Inst. & the Voyage of the Odyssey)
    191 Weston Road, Lincoln, MA 01773
    781.259.0423 ext. 14 fax 259.0288
    www.oceanalliance.org www.pbs.org/odyssey
    Please support our efforts to conserve whales and their ocean environment
    through research and education :)



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