Airgun UW movie

Seismic airgun bubble pulse and oscillation:

Noise disrupts interdependencies in the web of life

While it is easier to evaluate specific impacts of a stimulus on specific animals, we know that nature is not just a catalog of individual species; rather it is a fabric of interdependent organisms living in interconnected physical habitats.

This point is punctuated in a recent paper on the Proceedings of the Royal Society that evaluates the noise impacts of gas well fields on the pollination and dispersal of piñon pine seedlings in New Mexico.

Aerial view of roads and pipes of a fracking field operation

Aerial view of roads and pipes of a fracking field operation

Gas wells use compressors which can be really noisy. The paper examines how the noise of a compressor field impacts hummingbirds that pollinate the piñons, and blue jays that disperse the piñon seeds. They found that the number of piñon seedlings were one quarter the density in the noisy compressor area than in quiet areas. This would indicate that the hummingbirds are not bothered by the noise, but the jays are.

This negative seed dispersal condition is further amplified by the fact that mice that eat the seeds are also not bothered by the noise, so that while there is no negative impact on pollination, the seeds that are produced are eaten by mice rather than distributed by jays.

Pazflor Field Layout for sea-floor processing

Pazflor Field Layout for sea-floor processing

This is an example of how noise disrupts a simple set of relationships between three species of vertebrates, and how the disruption impacts one species of tree.

We know quite a bit about terrestrial interdependencies because we spend most of our time “on the ground.” But we can be sure that the ocean is full of equally important interdependencies which we have yet to discover.

This adds yet another dimension we should consider as we roll unmitigated noise sources into the ocean.

Okeanos – Dance, Art, and Science in San Francisco

The performance company “Capacitor” will be presenting ocean-themed “Okeanos” from April 12 through April 15 at Fort Mason’s Herbst Theater in San Francisco.

From their words: “Okeanos is an immersive dance/circus/video experience that will inspire and educate audiences about the ocean, catalyze interest in art/science collaborations, and help to raise funds and awareness for marine protected areas.”

Dance performance, "Okeanos", presented by Capacitor

Dance performance, "Okeanos", presented by Capacitor

Each evening will include a panel of ocean experts before the show, the performance, and an “Ocean Solutions Café” after the show featuring table discussions with other ocean experts.

The whole event should be a great opportunity to hear about current ocean issues, experience a deep aesthetic journey into the sea, and get together with folks in the ocean science and conservation community to speak about the issues.

Capacitor presents OkeanosSome of the experts include Dr. Sylvia Earle, J. Wallace Nichols, Tierney Thys, and a host of others across the ocean conversation.

I will be hosting table discussions on Saturday and Sunday.

C’mon down! These events should be as sensuous, informative, and delightful a dive into the ocean you could have without getting wet.

Oil and Gas exploration implicated in dolphin strandings

2012 Gulf Dolphin Samples – NMFS Photo

Over 675 dolphins have been found dead along the Florida to Texas Gulf Coast since February 2010. Initially people suspected that the BP oil spill and dispersant use might be to blame. A report from NOAA corroborates this with a finding that some 32 live dolphins show signs of chemical stress with liver and lung damage, and other metabolic compromises.

But reports from other research do not show chemical damage, and some focus has shifted over to acoustical exploration for oil and gas. The concern for acoustical trauma has prompted the Bureau of Ocean Energy Management (BOEM) to restrict seismic exploration off Louisiana until May, when the dolphin calving season ends.

2012 Peru Dolphin Strandings

Heretofore there have been only loose correlations between seismic exploration and marine mammal strandings, but the tragic strandings of 2000-3000 dolphins this year in Peru has implicated acoustical surveys for oil and gas off Peru’s coast.

It could be that new technologies are being used for the surveys, or that the cumulative stresses of chemical pollution, depleted food sources, and acoustical trauma are causing a rise in strandings world-wide.

Whatever the cause(s), we can be sure that our growing thirst for fossil fuel plays some role in these tragedies.

Follow-up on the Arctic Five Year Oil and Gas exploration plan

A few weeks back we asked you all to sign on to a petition addressed to NOAA chief Dr. Jane Lubchenko expressing concerns about the rampant expansion of Arctic oil and gas exploration and production (E&P). Thanks to your participation and the outreach efforts of World Wildlife Fund we pulled in over 8500 signatures!

While it remains to be seen how effective the petition will be, your signatures were submitted along with our comments on the Draft Environmental Impact Statement for the Arctic Five-year Oil and Gas Exploration Plan (DEIS) – which was the specific focus of our concern.

Our comments drilled down into noise impacts only (pardon the pun), leaving comments on the impacts of oil spills, effluent discharge, drilling mud disposal, methane and other gas releases, physical habitat disruption, ship strikes, and the synergistic impacts of increased human activities to others.

While we brought up new data on the disruptions of seismic surveys, our comments also highlighted the noise sources from new “sub-sea” and deepwater technologies which have not yet been evaluated for noise impacts. These include seafloor processing, thruster-stabilized drilling platforms, and acoustic communication systems for autonomous vessel and equipment control.

We also brought up the point that while the DEIS evaluates various chronic noise sources independently (and thus constrained only by a 160dB re: 1µPa mitigation threshold) the ongoing noises of each of these technologies become an aggregate noise field that should be framed under the “continuous noise” mitigation threshold of 120 dB.

Consideration of aggregate and cumulative impacts has been detailed in a paper published this month in Bio Science, “A New Framework for Assessing the Effects of Anthropogenic Sound on Marine Mammals in a Rapidly Changing Arctic”.

Scientists, indigenous hunters, fishermen, environmental activists, conservationists, the British Parliament, American citizens, and even some enlightened American politicians are all trying to put the brakes on drilling the arctic. We all know that there is a lot at stake and none of us want to see this pristine environment destroyed just for a few years of petroleum profits.

But even with the ongoing global incidents of oil spills and other environmental damage (Shell had over 200 oil spills last year alone!) the Oilmen have been driving the issue of “need” solely based on the price of gas at the pump.

Hopefully cooler minds will prevail, regulators will heed our collective warnings (substantiated by your signatures) and Arctic Oil Extraction plans will be “put on ice” for an indefinite period of time.

Tracking walrus’ movement using only one ear

A recent paper was published by marine research firm JASCO on localizing walruses using a single hydrophone. The technique they have refined is detailed in the article and involves assessing “multipath signals” – echoes from the sea surface and seafloor – along with the direct signal to track the movements of walruses in the Arctic. This is remarkable because locating a sound source usually involves two or more receivers.

For example, all terrestrial vertebrates have two ears which allow us to locate sound sources. We do this using a number of different cues. One of the obvious cues is amplitude: if the sound is louder in one ear over the other we assume that the sound source is closer to the louder ear. Another more subtle cue is ‘time of arrival’ which allows us to locate a sound source by the difference between the times it takes for the sound to arrive at one ear and the other.

These two cues serve to give us a general bead on the horizontal source of a sound – whether it is to the left or right, in front of us or somewhere in between. This method is adequate for birds, frogs, and lizards in the context of their survival needs.

But we mammals have more complex localizing needs from sound so we have developed outer ears that provide us with more subtle cues – allowing us to determine things such as how close or far, and the height or azimuth of a sound.

Mammals with movable ears such as cats and horses can use their outer ears like periscopes to hone in on a source of sound. Primates such as us humans have fixed ears, so we derive location cues from secondary reflections off the pinnae of our ear.

It happens that all the whorls on our outer ears collect and reflect sound into our ear canal with a tiny time delay after the primary sound hits our ear drums. This is a bit like the “multipath” cues that JASCO teased out in their work (but with much less math).

These three cues – amplitude, time of arrival, and delay of the secondary reflection allows us to pinpoint the source of a sound with uncanny accuracy.

Of course marine mammals (with the exception of sea lions, polar bears, and otters) do not have outer ears. We know that they have equal, or even more complex localizing needs from sound, especially the Arctic animals that spend a good amount of time in the deep and dark waters of the Arctic winter.

It has been less than 100 years that humans have started to use sonar in marine environments. The folks at JASCO are rolling back sonar frontiers, showing us that complex data can be derived from single receivers.

Marine mammals such as whales and seals have been adapting to their acoustic environment for 20-30 million years. It stands to reason that these animals have evolved some pretty complex adaptations to sound perception.

Hopefully we can come to understand and learn from some of these adaptations before we cloud out their arctic environment with sounds to which they have not adapted.

Jasco graph describing walrus localization

Jasco graph describing walrus localization

Marine Bio-acoustics lecture at Hopkins Marine Station, Monterey

Two OCR events for tomorrow – Thursday February 23:

Radio interview:

For those in the SF Bay Area I will be presenting a few words on our Arctic campaign on Pacifica’s “Visionary Activists Show” with Caroline Casey

Where: 94.1 or

When: 2:00 pm



For those of you in the Monterrey Bay area I will be giving a presentation on marine mammal acoustic adaptations sponsored by the Monterey chapter of the American Cetacean Society. Slides, sounds, and Q&A – preceded by a sound environment piece assembled by ACS Chapter director Bob Mannix .

Hopkins Marine Station
120 Oceanview Blvd.,
Pacific Grove, CA 93950
Adjacent to the Monterrey Bay Aquarium

Thursday February 23,
7:00 pm for refreshments,7:30 pm for the lecture

The event is open to the public at no charge.
For more information visit:

I hope to see you there!



Here are the recordings of the radio interviews with Caroline Casey on “Visionary Activist”, KPFA

Shipping noise correlated to stress in whales

A recent paper in the Proceedings of the Royal Society correlates shipping noise with stress levels in baleen whales. Heretofore this has been a difficult assumption to prove because we do not have any baseline of whale stress levels prior to the introduction of the vast shipping networks we now use in global trade.

Map of shipping routes

Researchers can get an idea of metabolic stress levels because they are correlated to hormone indicators (glucocorticoids) in body fluids. Rosalind Rolland with the New England Aquarium was studying the glucocorticoids in the feces of North Atlantic Right whale in the Bay of Fundy through September 2001. She was doing this research concurrently with a study on Right whale social behavior being conducted by Susan Parks with Penn State and Syracuse University.

Both of these studies overlapped the September 11 tragedy and the subsequent halting of air and sea transportation for a few days. It was across this time that the noise levels in the ocean decreased significantly. Parks, Rolland and other colleagues brought their work together and noticed a marked decrease in stress indicators with the decrease in shipping noise.

Whale Feces Sniffing Dog

This is a real benchmark to our understanding of how chronic anthropogenic noise impacts baleen whales – which are too large to test in lab settings and not really interested in cooperating with behavioral scientists in the wild. Given that the glucocorticoids are part of a feedback mechanism in the immune system, this finding also confirms concerns that shipping noise compromises the health of these whales.

The paper is discussed in “lay” terms in a Science article that also introduces us to the critically important scientific instrument, a dog – whose nose can pinpoint whale feces in the ocean. (The dog was not included as a co-author on the paper.)

This paper should provide us with important supporting data as we attempt to slow industrial development in the pristine acoustic environment of Arctic.

Marine Scientists express themselves through CNN

An article appeared today in “CNN Opinion” by Chris Clark and Brandon Southall focused on the impacts of noise on marine life. It is an informative read and also highlights two important trends in the field.

First, it points to a trend in impact awareness and research from incident-specific catastrophic impacts (such as sonar induced mass strandings) toward chronic compromise of habitat due to “sub-lethal” noise sources such as shipping noise and seismic airgun surveys. This keys into the more holistic “Ecosystem Based Management” concept introduced into NOAA’s regulatory framework by NOAA director Jane Lubchenko when she took the reins in 2009.

The second important trend is that noted scientists are stepping forward with opinions and recommendations – something that until recently was not in most scientists repertoire. This trend is becoming exceedingly critical given the more rapacious and troubling trend of policy makers and industry moguls of just making up convenient lies without regard for scientific fact – ignoring the hard, methodical work that scientists do to assure the integrity of their findings.

Drs. Clark and Southall are at the vanguard of this trend which will hopefully encourage scientists in all fields to reach out to the public with their findings. Given the urgent state of our global habitat – frayed by the frenzied drive of “The Economy,” scientific voices are profoundly needed to inform and influence public opinion and policies.

Thanks guys!

BBC Focus on Sounds of the Sea

Yesterday BBC News put out a feature article on ocean acoustics. I suspect that this is really making the rounds because many folks have brought it to our attention. For good reason too, as it includes some great embedded sounds, references to other useful resources, and a couple of conversations with folks in the field, such as Chris Clark with Cornell Ornithology Lab, and Michel Andre whose “Listening to Deep Ocean” we covered in a January 2011 Newsletter.

It is encouraging that ocean bioacoustics is increasingly becoming “main-stream,” particularly in light of the fact that the reach of human noise is ever saturating into further reaches of the sea – requiring all of us to be better informed about how marine animals use their acoustic habitat, and how human noise is transforming it.

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