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An inside look at the science of cleaning up and fixing the mess of marine pollution


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Science of Oil Spills Training: Apply for Fall 2016

Two men speaking on a beach with a ferry in the background.

Science of Oil Spills classes help new and mid-level spill responders better understand the scientific principles underlying oil’s fate, behavior, and movement, and how that relates to various aspects of cleanup. The classes also inform responders of considerations to minimize environmental harm and promote recovery during an oil spill. (NOAA)

Science of Oil Spills (SOS) classes help spill responders increase their understanding of oil spill science when analyzing spills and making risk-based decisions.

NOAA’s Office of Response and Restoration, a leader in providing scientific information in response to marine pollution, has scheduled an autumn Science of Oil Spills (SOS) class in Portsmouth, New Hampshire, October 3-7, 2016.

OR&R will accept applications for this class through Monday, August 15, and will notify accepted participants by email no later than Monday, August 22.

SOS classes help spill responders increase their understanding of oil spill science when analyzing spills and making risk-based decisions. They are designed for new and mid-level spill responders.

The trainings cover:

  • Fate and behavior of oil spilled in the environment.
  • An introduction to oil chemistry and toxicity.
  • A review of basic spill response options for open water and shorelines.
  • Spill case studies.
  • Principles of ecological risk assessment.
  • A field trip.
  • An introduction to damage assessment techniques.
  • Determining cleanup endpoints.

To view the topics for the next SOS class, download a sample agenda [PDF, 170 KB].

Please understand that classes are not filled on a first-come, first-served basis. We try to diversify the participant composition to ensure a variety of perspectives and experiences, to enrich the workshop for the benefit of all participants. Classes are generally limited to 40 participants.

For more information, and to learn how to apply for the class, visit the SOS Classes page.


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Improving Currents Predictions for Washington Waters Will Help Efforts to Prevent and Respond to Oil Spills

Front of a kayak pushing through floating wood in the Strait of Juan de Fuca.

Kayakers and oil spill responders alike will appreciate the updated currents predictions NOAA is producing from a survey of Washington’s Puget Sound, San Juan Islands, and Strait of Juan de Fuca. (Courtesy of Amy MacFadyen)

This is a post by Amy MacFadyen, NOAA oceanographer and modeler in the Office of Response and Restoration’s Emergency Response Division.

As a sea kayaking enthusiast who enjoys paddling the waters of Washington’s Puget Sound, I need to have up-to-date information about the currents I’m passing through. Accurate predictions of the strong tidal currents in the sound are critical to safe navigation, and kayak trips in particular need to be timed carefully to ensure safe passage of certain regions.

As a NOAA oceanographer and modeler, I also depend on accurate information about ocean currents to predict where spilled pollutants may travel in the marine environment.

Sound Information

These are two reasons I was excited to learn that NOAA’s Center for Operational Oceanographic Products and Services (CO-OPS) is performing a scientific survey of currents in the marine waters of the Puget Sound, the San Juan Islands, and the Strait of Juan de Fuca. They began in the south sound in the summer of 2015, deploying almost 50 devices known as Acoustic Doppler Current Profilers to measure ocean currents at various depths throughout the water column.

Work is getting underway this summer to continue gathering data. The observations collected during this survey will enable NOAA to provide improved tidal current predictions to commercial and recreational mariners. But these updated predictions will also help my line of work with oil spill response.

When oil spills occur at sea, NOAA’s Office of Response and Restoration provides scientific support to the Coast Guard, including predictions of the movement and fate of the oil. Accurate predictions of the oil trajectory may help responders protect sensitive shorelines and direct cleanup operations.

Spills Closer to Home

U.S. Coast Survey nautical chart of Washington's Puget Sound in 1867.

A U.S. Coast Survey nautical chart showing the complex channels of Puget Sound when Washington was just a territory in 1867. (NOAA)

In the last few years, I’ve modeled oil movement for numerous spills and traveled on scene to assist in the oil spill response.

Seeing oil on the water and shorelines of places ranging from Santa Barbara, California, to Matagorda Island, Texas, I can’t help but think about both the possibility of a spill closer to my home in Puget Sound and our ability to model the movement of the oil there.

When oil spills in the marine environment, it spreads quickly, forming thin slicks on the ocean surface that are transported by winds and currents.

Puget Sound is a glacially carved fjord system of interconnected marine waterways and deep basins separated by shallower regions called sills.

Tidal currents in these narrow, silled connection channels can reach fairly swift speeds of up to 5-6 mph, whereas in the deep basins the currents are much slower (typically less than 1-2 mph).

Accurate predictions of currents within the sound will be critical to forecasting oil movement. Today’s predictions for this region rely on limited amounts of data gathered from the 1930s-1960s. Thanks to both these current surveys and modern technological advances, we can expect significant progress in the accuracy of these predictions.

The information collected on the NOAA current surveys will also be used to support the creation of an Operational Forecast System for Puget Sound, a numerical model which will provide short-term forecasts of water level, currents, water temperature, and salinity—information that is critical to oil spill trajectory forecasting.

Making Safer Moves

A fuel barge in Puget Sound on a cloudy day.

With the methods for transporting oil through Washington rapidly shifting and the number of vessels carrying oil increasing, the risks for oil spills are changing as well. Here, a fuel barge passes through Puget Sound. (NOAA)

More accurate current and water level predictions are good for oil spill modeling, but they are even better for oil spill prevention by making navigating through our waterways safer.

Until fairly recently, 90% of the oil moving through Washington (mainly to and from refineries) traveled by ship. But by 2014, that number dropped to less than 60%, with rail and pipelines making up the difference.

Because the methods for transporting oil through Washington are shifting, the risks for oil spills shift as well. However, even with the recent increase in crude oil being delivered by train, the number of vessels transporting oil through state waters has gone up as well, increasing the risk of a large oil spill in Puget Sound.

With such a dynamic oil transportation system and last December’s repeal of a decades-long ban on exporting U.S. crude oil, the Washington Department of Ecology has decided to update its vessel traffic risk assessment for the Puget Sound. Results from the risk assessment will ultimately be used to inform spill prevention measures and help us become even better prepared to respond to a spill.

The takeaway? Both state and federal agencies are working to make Washington waters safer.

Amy MacFadyenAmy MacFadyen is a physical oceanographer at the Emergency Response Division of the Office of Response and Restoration (NOAA). The Emergency Response Division provides scientific support for oil and chemical spill response — a key part of which is trajectory forecasting to predict the movement of spills. During the Deepwater Horizon oil spill in the Gulf of Mexico, Amy helped provide daily trajectories to the incident command. Before moving to NOAA, Amy was at the University of Washington, first as a graduate student, then as a postdoctoral researcher. Her research examined transport of harmful algal blooms from offshore initiation sites to the Washington coast.


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NOAA Supporting Spill Response in the Green Canyon Oil Reserve Area of the Gulf of Mexico

Vessels skim oil from the surface of the Gulf of Mexico.

Vessels conduct skimming operations, May 14, 2016, in response to an estimated 88,200 gallons of crude oil discharged from a segment of flow line at the Glider Field approximately 90 miles south of Timbalier Island, Louisiana. As of May 15, the vessels have removed a combined total of more than 51,000 gallons of oily-water mixture since the discharge on May 12, 2016. (U.S. Coast Guard)

NOAA’s Office of Response and Restoration is supporting the U.S. Coast Guard response to an oil spill in the Green Canyon oil reserve area in the Gulf of Mexico. We are providing oil spill trajectory analysis and information on natural resources potentially at risk from the oil. The NOAA Scientific Support Coordinator has been on-scene.

The spill occurred at approximately 11:00 a.m. on May 12, 2016 when 2,100 barrels (88,200 gallons) of oil was discharged from a Shell subsea well-head flow line at the Glider Field. Since then, the source has been secured and the pipeline is no longer leaking. The U.S. Coast Guard reports that the spill happened approximately 90 miles south of Timbalier Island, Louisiana.

We are providing scientific support, including consulting with natural resource trustees and environmental compliance requirements, identifying natural resources at risk, coordinating overflight reports, modeling the spill’s trajectory, and coordinating spatial data needs, such as displaying response data in a “common operational picture.” The reported oil trajectory is in a westerly direction with no expected shoreline impact at this time.

For more details, refer to the May 15 U.S. Coast Guard press release or the May 15 Shell Gulf of Mexico Response press release.


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How Does NOAA Model Oil Spills?

Dark oil drifts near the populated shores of Berkeley and Emerville, California.

After the cargo ship M/V Cosco Busan struck the San Francisco-Oakland Bay Bridge in 2007, NOAA oceanographers modeled how wind, waves, tides, and weather would carry the ship’s fuel oil across San Francisco Bay. Here, dark oil drifts near the shores of Berkeley and Emerville, California, on November 9, 2007. (NOAA)

One foggy morning in 2007, a cargo ship was gliding across the gray waters of San Francisco Bay when it ran into trouble, quite literally. This ship, the M/V Cosco Busan, struck the Bay Bridge, tearing a hundred-foot-long gash in its hull and releasing 53,000 gallons of thick, sticky fuel oil into the bay.

When such an oil spill, or even the threat of a spill, happens in coastal waters, the U.S. Coast Guard asks the oceanographers at NOAA’s Office of Response and Restoration for an oil spill trajectory.

Watch as NOAA’s Ocean Service breaks down what an oil spill trajectory is in a one-minute video, giving a peek at how we model the oil’s path during a spill.

Using a specialized NOAA computer model, called GNOME, our oceanographers forecast the movement of spilled oil on the water surface. With the help of data for winds, tides, weather, and ocean currents, they model where the oil is most likely to travel and how quickly it may come ashore or threaten vulnerable coastal resources, such as endangered seabirds or a busy shipping lane.

During the Deepwater Horizon oil spill, we produced dozens of oil spill trajectory maps, starting on April 21 and ending August 23, 2010, when aerial surveys and satellite analyses eventually showed no recoverable oil in the spill area. You can download the trajectory maps from that spill.

Swirls of oil on the surface of San Francisco Bay west of the Golden Gate Bridge.

Specially trained observers fly over oil spills to gather information that is fed back into NOAA’s trajectory model to improve the next forecast of where the oil is going. (NOAA)

Learn more about how we model and respond to oil spills:

Attempting to Answer One Question Over and Over Again: Where Will the Oil Go?

“Over the duration of a typical spill, we’ll revise and reissue our forecast maps on a daily basis. These maps include our best prediction of where the oil might go and the regions of highest oil coverage, as well as what is known as a “confidence boundary.” This is a line encircling not just our best predictions for oil coverage but also a broader area on the map reflecting the full possible range in our forecasts [PDF].

Our oceanographers include this confidence boundary on the forecast maps to indicate that there is a chance that oil could be located anywhere inside its borders, depending on actual conditions for wind, weather, and currents.”

A Bird’s Eye View: Looking for Oil Spills from the Sky

“Aerial overflights are surveys from airplanes or helicopters which help responders find oil slicks as they move and break up across a potentially wide expanse of water … Overflights give snapshots of where the oil is located and how it is behaving at a specific date and time, which we use to compare to our oceanographic models. By visually confirming an oil slick’s location, we can provide even more accurate forecasts of where the oil is expected to go, which is a key component of response operations.”

Five Key Questions NOAA Scientists Ask During Oil Spills

“Responders can potentially clean up what is on top of the water but recovering oil droplets from the water column is practically impossible. This is why it is so important to spill responders to receive accurate predictions of the movement of the surface slicks so they can quickly implement cleanup or prevention strategies.”


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Looking Back: Six Years Since Deepwater

beach-grasses (4)Wednesday, April 20, is the six-year anniversary of the blowout on the Deepwater Horizon oil rig in the Gulf of Mexico.  That terrible incident was the start of a three month-long oil spill that spilled millions of gallons per day until the well was capped on July 15, 2010.    The cleanup took years to complete, the natural resource damage assessment was just finalized this spring, and restoration activities will take decades to complete.  Many long-term research projects are underway and we are still learning about the effects of the spill on the environmental and the coastal communities of the Gulf of Mexico.

On April 4, 2016, the court approved a settlement with BP for natural resource injuries stemming from the Deepwater Horizon oil spill. This settlement concludes the largest natural resource damage assessment ever undertaken. It is safe to say that scientists will be publishing papers and results for decades.  For many of the people involved, the Deepwater Horizon oil spill is considered THE SPILL, the same way the generation of scientists that worked on the Exxon Valdez Spill in Alaska almost 30 years ago consider that event.  We even keep track of events in a rough vernacular based on those incidents.  Post-Deepwater, or Pre-OPA (the Oil Pollution Act, passed in 1990, the summer after the Exxon Valdez spill).  But while those spills generate most of the publicity, policy interest, and research, responders in NOAA and the U.S. Coast Guard and other agencies know that spills are a routine occurrence.  Since the Deepwater Horizon spill, NOAA’s Office of Response and Restoration has responded to over 800 other incidents.  Most are ones that you’ve probably never heard off, but here are a few of the larger incidents since Deepwater.

Enbridge Pipeline Leak, Kalamazoo, Michigan:  On July 25, 2010, while the nation was fixated on the spill in the Gulf of Mexico, an underground pipeline in Michigan also began gushing oil. More than 800,000 gallons of crude oil poured out of the leaking pipeline and flowed along 38 miles of the Kalamazoo River, one of the largest rivers in southern Michigan. The spill impacted over 1,560 acres of stream and river habitat as well as floodplain and upland areas, and reduced recreational and tribal uses of the river. A natural resource damage assessment was settled in 2015 that will result in multiple resource restoration projects along the Kalamazoo River.

Two kayakers on the river with vegetation visible on the water in foreground.

Kayaking on the Kalamazoo River. (NOAA)

Exxon Mobil Pipeline Rupture, Yellowstone River, Montana:  On July 1, 2011, an ExxonMobil Pipeline near Billings, Montana, ruptured, releasing an estimated 31,500 to 42,000 gallons of oil into the iconic river, which was at flood-stage level at the time of the spill.  Oil spread downstream affecting sensitive habitats.

Paulsboro, New Jersey Rail Accident and Release: On November 30, 2012, a train transporting the chemical vinyl chloride derailed while crossing a bridge that collapsed over Mantua Creek, in Paulsboro, N.J., near Philadelphia. Four rail cars fell into the creek, breaching one tank and releasing approximately 23,000 gallons of vinyl chloride. A voluntary evacuation zone was established for the area, and nearby schools were ordered to immediately take shelter and seal off their buildings.

Molasses Spill, Honolulu, Hawaii: On September 8, 2013, a faulty pipeline operated by Matson Shipping Company leaked 233,000 gallons (1,400 tons) of molasses into Hawaii’s Honolulu Harbor.  A large fish kill resulted.

Texas “Y” collision, Galveston, Texas:  On March 22, 2014, the 585 foot bulk carrier ‘M/V Summer Wind’ collided with an oil tank-barge, containing 924,000 gallons of fuel oil.  The collision occurred at the intersection or “Y” in Lower Galveston Bay, where three lanes of marine traffic converge: vessels from the Port of Texas City, the Houston Ship Channel and the Gulf Intracoastal Waterway.   The collision breached the hull of the tank barge, spilling about 168,000 gallons of fuel oil spilled into the waterway. A natural resource damage assessment is underway, evaluating impacts to shoreline habitats, birds, bottlenose dolphins, and recreational uses.

Refugio State Beach Pipeline Rupture, California:   On May 19, 2015, a 24-inch crude pipeline ruptured near Refugio State Beach in Santa Barbara County, California. Of the approximately 100,000 gallons of crude oil released, some was captured and some flowed into the Pacific Ocean.  The spill raised many challenges. The spill occurred in an especially sensitive region of the coast, known for its incredible diversity of marine life and home to the Channel Islands National Marine Sanctuary. The Refugio spill site is also the site of one of the most historically significant spills in U.S. history. Just over 46 years ago, off the coast of Santa Barbara, a well blowout occurred, spilling as much as 4.2 million gallons of oil into the ocean. A natural resource damage assessment for the Refugio spill is underway, focusing on impacts to wildlife, habitat, and lost recreational uses.

Two people in cleanup suits with a shovel stand on a beach with oiled rocks.

Two cleanup crew members work to remove oil from the sand along a portion of soiled coastline near Refugio State Beach, on May 23, 2015. (U.S. Coast Guard)

Barge APEX 3508 Collision, Columbus, Kentucky:  On September 2, 2015, two tug boats collided on the Mississippi River near Columbus, Kentucky, spilling an estimated 120,500 gallons of heavy oil.  The oil sank to the river bottom and had to be recovered by dredge.

Train Derailment, West Virginia:  On February 16, 2015, a CSX oil train derailed and caught fire in West Virginia near the confluence of Armstrong Creek and the Kanawha River. The train was hauling 3.1 million gallons of Bakken crude oil from North Dakota to a facility in Virginia. Of the 109 train cars, 27 of them derailed on the banks of the Kanawha River, but none of them entered the river. Much of the oil they were carrying was consumed in the fire, which affected 19 train cars, and an unknown amount of oil reached the icy creek and river.

Each year NOAA’s Office of Response and Restoration is asked to respond to an average of 150 incidents, and so far this year we have been asked for help with 43 incidents. Most of these were not huge, and include groundings in Alaska, Oregon, Washington, and Hawaii; five sunken vessels, fires at two marinas, a burning vessel, and an oil platform fire; nine oil spills and a chemical spill; and multiple “mystery sheens”—slicks of oil or chemicals that are spotted on the surface of the water and don’t have a clear origin. Since 1990, we have responded to thousands of incidents, helping to guide effective cleanups and protect sensitive resources. Also since 1990 and with our co-trustees, we have settled almost 60 spills for more than $9.7 billion for restoration. We hope that we will never have to respond to another “Deepwater” or “Exxon Valdez”, but should a large disaster occur, we will be ready. In the meantime, smaller accidents happen frequently and we are ready for those, too.

Doug Helton and Vicki Loe contributed to this post.


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Supporting the Response to a Platform Fire and Oil Spill in Bayou Sorrel, Louisiana

Fire burns in one of several oil tanks on a platform in a bayou.

The Coast Guard, with state and local partners, is responding to an oil production platform fire in Bayou Sorrel, Louisiana, March 15, 2016. One of the tanks reportedly collapsed, releasing an unknown amount of crude oil into a canal. (U.S. Coast Guard)

On the morning of March 15, 2016, the U.S. Coast Guard requested assistance from NOAA‘s Office of Response and Restoration for an oil production platform fire near Berry Lake in Bayou Sorrel, Louisiana.

While crews were working to dismantle the platform, one of the oil storage tanks caught fire. No injuries have been reported. The U.S. Coast Guard is leading the response with state and local agencies.

The platform and one of its storage tanks burned throughout the day on March 15 before the tank partially collapsed, releasing crude oil into a canal. Most of the oil released from the tank continued to burn on the water surface and was consumed.

Responders contained the remaining oil and burn residue in the canal with boom.

Fire-fighting vessel sprays water on an oil tank on a platform in a bayou.

Response crews extinguished the fire on the oil production platform and will continue to monitor the scene in Bayou Sorrel, Louisiana. (U.S. Coast Guard)

A second tank on the platform subsequently caught fire but has been extinguished. The two storage tanks had a maximum capacity of more than 33,000 gallons of crude oil.

We are assisting the Coast Guard’s response by coordinating local weather forecast support, modeling the potential trajectory of spills of oil or burn residue, and outlining the wildlife and habitats that could be at risk in the area. A NOAA Scientific Support Coordinator has reported to the response to provide further help and assess potential impacts of the oil spill.

Bayou Sorrel is predominantly composed of seasonally flooded, forested wetlands with some patches of freshwater marshes and open canals. While oil is unlikely to penetrate flooded or water-saturated soils, it will readily coat and become mixed with floating debris such as branches and leaves.

A variety of birds, particularly diving and wading birds and waterfowl, may be present in the area and might be at risk of coming into contact with oil, which can coat their feathers, be ingested, or inhaled. In addition, fish and invertebrates such as crawfish may be present or spawning in the marshy habitats surrounding the oil platform, and alligators and small-to-medium-sized mammals including mink and river otters may be nearby.

In 2013, NOAA provided on-site technical support for an oil spill from a pipeline in Bayou Sorrel and helped coordinate a controlled burn of the spilled oil in the area’s flooded, wooded swamps. Additionally, we assisted with other oil spills in this area in 2015, 2007, and 1988.

Look for more information about the current oil spill and fire here and at the U.S. Coast Guard’s media site.


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For the First Time in Decades, Scientists Examine How Oil Spills Might Affect Baleen Whales

A North Atlantic right whale's mouth is visible at the ocean surface.

NOAA scientists and partners recently collaborated to examine how oil and dispersants might affect the function of baleen in humpback, bowhead, and right whales (pictured). Hundreds of baleen plates hang from these whales’ top jaws and allow them to filter food from the water. (Credit: Georgia Department of Natural Resources, Permit 15488)

Several days of unseasonably warm weather in late September had Gary Shigenaka starting to wonder how much longer he and his colleagues would be welcome at Ohmsett, a national oil spill research facility in New Jersey.

They were working with whale baleen, and although the gum tissue anchoring their baleen samples had been preserved with formalin, the balmy fall weather was taking a toll. As a result, things were starting to smell a little rank.

Fortunately, cooler weather rounded out that first week of experiments, and the group, of course, was invited back again. Over the course of three week-long trials in September, December, and January, they were trying to tease out the potential impacts of oil and dispersants on whale baleen.

As a marine biologist with NOAA’s Office of Response and Restoration, Shigenaka’s job is to consider how oil spills might threaten marine life and advise the U.S. Coast Guard on this issue during a spill response.

But the last time scientists had examined how oil might affect whale baleen was in a handful of studies back in the 1980s. This research took place before the 1989 Exxon Valdez and 2010 Deepwater Horizon oil spills and predated numerous advances in scientific technique, technology, and understanding.

Thanks to a recent opportunity provided by the U.S. Bureau of Safety and Environmental Enforcement, which runs the Ohmsett facility, Shigenaka and a team of scientists, engineers, and oil spill experts have been able to revisit this question in the facility’s 2.6 million gallon saltwater tank.

The diverse team that made this study possible hails not just from NOAA but also Alaska’s North Slope Borough Department of Wildlife Management (Dr. Todd Sformo), Woods Hole Oceanographic Institution (Dr. Michael Moore and Tom Lanagan), Hampden-Sydney College (Dr. Alexander Werth), and Oil Spill Response Limited (Paul Schuler). In addition, NOAA’s Marine Mammal Health and Stranding Response Program provided substantial support for the project, including funding and regulatory expertise, and was coordinated by Dr. Teri Rowles.

Getting a Mouthful

To understand why this group is focused on baleen and how an oil spill might affect this particular part of a whale, you first need to understand what baleen is and how a whale uses it. Similar to fingernails and hooves, baleen is composed of the protein keratin, along with a few calcium salts, giving it a tough but pliable character.

A hand holds a ruler next to oiled baleen hanging from a clamp next to a man.

Made of the flexible substance keratin, baleen plates have tangles of “fringe hair” that act as nets to strain marine life from mouthfuls of ocean water. This study examined how oil and dispersants might affect the performance of baleen. (NOAA)

Twelve species of whales, including humpback and bowhead, have hundreds of long plates of baleen hanging from the top jaw, lined up like the teeth on a comb, which they use to filter feed. A whale’s tongue rubs against its baleen plates, fraying their inner edges and creating tangles of “fringe hair” that act like nets to catch tiny sea creatures as the whale strains massive gulps of ocean water back out through the baleen plates.

Baleen does vary somewhat between species of whales. Some might have longer or shorter baleen plates, for example, depending on what the whale eats. Bowhead whales, which are Arctic plankton-eaters, can have plates up to 13 feet long.

This study was, at least in part, inspired by scientists wondering what would happen to a bowhead whale if a mouthful of water brought not just lunch but also crude oil from an ill-fated tanker traversing its Arctic waters.

Would oil pass through a whale’s hundreds of baleen plates and coat their mats of fringe hairs? Would that oil make it more difficult for the whale to push huge volumes of water through the oily baleen, causing the whale to use more energy as it tried? Does that result change whether the oil is freshly spilled, or weathered with age, or dispersed with chemicals? Would dispersant make it easier for oil to reach a whale’s gut?

Using more energy to get food would mean the whales then would need to eat even more food to make up for the energy difference, creating a tiring cycle that could tax these gargantuan marine mammals.

Testing this hypothesis has been the objective of Shigenaka’s team. While it might sound simple, almost nothing about the project has been straightforward.

Challenges as Big as a Whale

One of the first challenges was tackled by the engineers at Woods Hole Oceanographic Institution. They were tasked with turning the mechanical features of Ohmsett’s giant saltwater tank into, essentially, a baleen whale’s mouth.

Woods Hole fabricated a special clamp and then worked with the Ohmsett engineering staff to attach it to a corresponding mount on the mechanical bridges that move back and forth over the giant tank. The clamp gripped the sections of baleen and allowed them to be held at different angles as they moved through the water. In addition, this custom clamp had a load cell, which was connected to a computer on the bridge. As the bridge moved the clamp and baleen at different speeds and angles through the water, the team could measure change in drag on the baleen via the load cell.

With the mechanical portion set up, the Ohmsett staff released oil into the test tank on the surface of the water, and the team watched expectantly how the bridges moved the baleen through the thin oil slick. It turned out to be a pretty inefficient way to get oil on baleen. “How might a whale deal with oil on the surface of the water?” asked Shigenaka. “If it’s feeding, it might scoop up a mouthful of water and oil and run it through the baleen.” But how could they simulate that experience?

They tried using paintbrushes to apply crude oil to the baleen, but that seemed to alter the character of the baleen too much, matting down the fringe hairs. After discussions with the Ohmsett engineering staff, the research team finally settled on dipping the baleen into a pool of floating oil that was contained by a floating ring. This set-up allowed a relatively heavy amount of oil to contact baleen in the water and would help the scientists calibrate their expectations about potential impacts.

Testing the Waters

Four black plumes of dispersed oil are released underwater onto long plates of baleen moving behind the applicator.

After mixing chemical dispersant with oil, the research team released plumes of it underwater in Ohmsett’s test tank as baleen samples moved through the water behind the applicator. Researchers also tested the effects of dispersant alone on baleen function. (NOAA)

In all, Shigenaka and his teammates ran 127 different trials across this experiment. They measured the drag values for baleen in a variety of combinations: through saltwater alone, with fresh oil, with weathered oil, with dispersed oil (pre-mixed and released underwater through a custom array designed and built by Ohmsett staff), and with chemical dispersant alone. They tested during temperate weather as well as lower temperature conditions, which clearly thickened the consistency of the oil. They conducted the tests using baleen from three different species of whales: bowhead, humpback, and right whale.

Following all the required regulations and with the proper permits, the bowhead baleen was donated by subsistence whalers from Barrow, Alaska. The baleen from other species came from whales that had stranded on beaches from locations outside of Alaska.

In addition to testing the potential changes in drag on the baleen, the team of researchers used an electric razor to shave off baleen fringe hairs as samples for chemical analysis to determine whether the oil or dispersant had any effects on baleen at the molecular level. They also determined how much oil, dispersed oil, and dispersant were retained on the baleen fringe hairs after the trials.

At this point, the team is analyzing the data from the experimental trials and plans to submit the results for publication in a scientific journal. NOAA is also beginning to create a guidance document on oil and cetaceans (whales and dolphins), which will incorporate the conclusions of this research.

While the scientific community has learned a lot about the apparent effects of oil on dolphins in the wake of the 2010 Deepwater Horizon oil spill, there is very little information on large whales. The body of research on oil’s effects on baleen from the 1980s concluded that there were few and transient effects, but whether that conclusion holds up today remains to be seen.

“This is another piece of the puzzle,” said Shigenaka. “If we can distill response-relevant guidance that helps to mediate spill impacts to whales, then we will have been successful.”

Work was conducted under NOAA’s National Marine Fisheries Service Permits 17350 and 18786.

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