photo: Brain Skerry

A nicely written article in the Dec. 3 2009 issue  Nature reveals how a how a neutrino detection experiment conducted in the Mediterranean Sea by nuclear physicists actually uncovered an abundance of sperm whales.

The experiment involved placing hydrophones down 2000 meters below the surface; the idea being that these hydrophones could detect little pops from neutrinos – sub-atomic particles zipping in from deep space.

Marine Biologists Giovanni Pavan was brought in to help filter out the background noise. What they found though was a proliferation of biological sounds, and a surprising high density of Sperm Whale vocalizations – which ended up shifting the focus of the study to monitoring populations of sperm whales.

The article mentions that the Nuclear Physicists somehow thought that the deep ocean would be a “quiet test chamber” for their studies. I find it telling that some of the smartest guys in the room (nuclear physicists) would be so siloed in their field that they would lose track of the fact that the ocean is teaming with ‘biologicals.’

This speaks volumes about our education model that focuses on specialization. It makes me worry about what I am missing when I scan the field I inhabit. But this tale also helps me cultivate more patience for those folks who “can not seem to grasp” the importance of our mission of preserving the ocean’s bio-acoustic sanctity.

This little sound sample is of the “carpenter fish” – an old mariner’s name for sperm whales, representative of what the scientists heard.

New Freeway planned for San Ignacio Lagoon

The Touch

San Ignacio Lagoon is the birthplace of a remarkable chapter in the relationship between whales and humans. The lagoons along the western coast of the American Continent- from San Francisco Bay in the north to Bahía Magdalena in the south – were all once breeding and birthing areas for the Eastern Pacific Gray Whales.

Shipping activities, harbor construction, oil extraction and processing and other human enterprises chased the whales out of many of their historic haunts (such as San Francisco and San Diego bays). Currently the only remaining breeding and birthing lagoons are the lagoons of Baja California – Guerrero Negro, San Ignacio, and Bahía Magdalena.

Of course decades of commercial whaling also played into this decimation of safe habitat and almost put the gray whales out of business. It was in fact these very lagoons where  some of the most voracious whaling occurred; whalers would go into the lagoons, attack the vulnerable baby whales and then capture and kill the mothers when they came to rescue their babies. This was a dangerous game for the whalers because unlike many baleen whales, the Gray Whale will attack their aggressors. One out of four whalers in the gray whale industry was either killed or maimed in these encounters – crowning the gray whale with the ominous name of “devilfish.”

Nonetheless the whaler’s strategies were so effective that by 1946 there were only a few thousand remaining whales, and commercial exploitation of the stock was no longer viable (and thus banned by the International Whaling Commission).

It was in San Ignacio Lagoon that this bloody history turned a page. In 1972, Pachico Mayoral, a fisherman in the Ejido of San Ignacio was out in his panga when a gray whale approached and began bumping and contacting the panga. Knowing the history and the dangerous behavior of these devilfish, Pachico was terrified. It seems that the devilfish tormented Pachico for hours; bumping and lifting his boat, scratching her belly on the hull, and peering over the gunwales into the boat.

It was during one of these “peering” maneuvers that Pachico gathered his courage and reached out to touch the beast. He says he felt “safe,” – that he realized that the whale ment him no harm.

When he finally returned home his family and community did not believe him. It took a few more encounters for the people to understand that within the whale’s living memory of the slaughter, these animals were forging a different relationship with the humans.

This relationship has blossomed into what is one of the most successful interspecies environmental businesses ever:  every year thousands of eco-tourists head down to the lagoons of Baja to meet the “friendly whales.”

I have been taking small groups to the lagoons over the years on what is almost a pilgrimage for some; to meet and interact with the baby whales and their mothers. These journeys are always transformative, and also just plain delightful.

We have been to both Bahía Magdalena and Laguna San Ignacio, though I have preferred the later because the bumpy dirt road across the desert has discouraged the concentrations of tourists you find in Magdalena. This lends to a more intimate experience in San Ignacio.

This will soon be changing though, because the highway department has begun construction of a paved road from the nearest town of San Ignacio to traverse the 60 km to the lagoon, and then head south to connect with the paved road at La Purisima.

The paved road will be a significant asset to the residents of the lagoon, improving access to commerce and tourism. The road will also significantly improve access to medical services for the residents of the lagoon. This road will change the relationship between the humans and the whales – and the human experience of the whale encounters – by dint of the fact that once the road is complete you can just blow out for an afternoon encounter and be back in town by evening.

Once the road connects to La Purisima, it will also become a preferred route for automotive and cargo traffic running north and south between the U.S. Mexico border and Cabo San Lucas because it bypasses the current, and fairly treacherous M-1 that runs between San Ignacio and Loreto.

This raises my concern that once the paved road becomes a main thoroughfare for heavy traffic, that seismic scale vibrations from the road will transfer low frequency noise into the lagoon and potentially compromise the habitat for the Gray whales.

In order to address this concern Ocean Conservation Research has put together a program determine the potential acoustical impacts of the road, measuring low frequency acoustical transmission characteristics of the lagoon/land interface where the road will flank the lagoon.

As with any non-profit we are spending more time gathering funds than doing the actual work. As of July 2009 we’re still shy of the complete budget, but research partner Aaron Thode has placed some hydrophones in the test area to get some benchmarks.

For a more detailed account of the project, see: San Ignacio Lagoon Freeway. Of course if you would like to support this project or participate, just contact me through info@OCR.org

Density of two months of large commercial vessel traffic in the sanctuary, with peak densities seen in the shipping lanes Density of two months of large commercial vessel traffic in the sanctuary, with peak densities seen in the shipping lanes

“Thrilling” is not a word I thought I would ever use in describing an Acoustical Society meeting, but there were moments last week that bordered on just that. Driving this is an intersection of rapidly increasing computer processing power and advancing sensor technologies – put in the hands of some of the nimble intellects that are making up the current crop of bio-acoustic post-docs.

Over the five days of the meeting there were many sessions on “Passive Acoustic Monitoring” (PAM) which presented many of the aspects of putting sensors in the ocean, collecting the data, and then making sense of it all. In practice this often means collecting the vocalizations of whales or dolphins over a period of time and watching the population dynamics change as a consequence of environmental conditions.

The output of these studies can be time-compressed animations of the peregrinations of dolphin schools or whale pods,[i] or in the case of Chris Clark, the acoustical impacts of ship traffic on humpback, fin and right whales.[ii] Dr. Clark’s animated display was a stunning “spatial-temporal” graphic of the changes in the hearing and communication range of these three whale species as a cargo ship passed over their habitat. I will make these graphics available on the OCR website once I get them from Chris, but meanwhile you can find out about the program here: http://stellwagen.noaa.gov/science/passive_acoustics_noise.html

Another telling presentation by Manolo Costellote came from his PAM study of the seasonal migration of fin whales in the Mediterranean Sea over a three year period. During one of the seasons there happened to be a concurrent seismic airgun survey. The monitoring clearly demonstrated that the whales avoided their traditional winter feeding areas throughout and even after of the survey. This indicates the acoustical impacts of airgun surveys reach over hundreds of kilometers for these animals.

Of course Manolo wanted to know where the surveys were taking place, and something about the sizes of the airgun arrays. He managed to locate the company doing the work, but they were predictably uncooperative. Not to be discouraged, he did a little sleuth work and found a “blog” of one of the crew members, which included the entire equipment list; airgun capacities, photographs of the ship, and pretty much everything he needed to calibrate his findings except for the exact locations of the survey (which he derived through some clever data evaluation).

It is work like this which may eventually put the current practices of airgun surveys “on the ropes” until the oil industry can find more benign ways of locating offshore oil.

Many other breakthroughs were presented and new ideas introduced over the course of the week across the field of acoustics. While overall the meeting was still pretty high on the “pencil-pocket” index, our field of marine bioacoustics is going through a thrilling sea change.

Stay tuned!

[ii] Christopher W. Clark “Result ad insights from operational monitoring networks”