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10 Photos That Tell the Story of the Exxon Valdez Oil Spill and its Impacts

Exxon Valdez ship with response vessels in Prince William Sound.

The single-hull tanker Exxon Valdez ran aground on Bligh Reef in Prince William Sound, Alaska, March 24, 1989, spilling 11 million gallons of crude oil. (U.S. Coast Guard)

While oil spills happen almost every day, we are fortunate that relatively few make such large or lasting impressions as the Deepwater Horizon or Exxon Valdez spills. Before 2010, when the United States was fixated on a gushing oil well at the bottom of the Gulf of Mexico, most Americans could probably only name one spill: when the tanker Exxon Valdez released 11 million gallons of crude oil into Alaska’s Prince William Sound on March 24, 1989.

Here we’ve gathered 10 photos that help tell the story of the Exxon Valdez oil spill and its impacts, not only on the environment but also on science, policy, spill response, school kids, and even board games. It has become a touchstone event in many ways, one to be learned from even decades after the fact.

1. Time for safety

Calendar showing March 1989 and image of Exxon Valdez ship.

In an ironic twist of fate, the Exxon Shipping Company’s safety calendar featured the tanker Exxon Valdez in March 1989, the same month the ship ran aground. Image: From the collection of Gary Shigenaka.

Long before the Exxon Valdez tanker ran aground on Bligh Reef in Prince William Sound, a series of events were building that would enable this catastrophic marine accident to unfold as it did. These actions varied from the opening of the Trans-Alaska Pipeline in the 1970s to the decision by the corporation running that pipeline to disband its oil spill response team and Exxon’s efforts to hold up both the tanker Exxon Valdez and its captain, Joseph Hazelwood, as exemplars of safety.

Captain Hazelwood received two Exxon Fleet safety awards for 1987 and 1988, the years leading up to March 1989, which was coincidentally the month the Exxon Valdez was featured on an Exxon Shipping Company calendar bearing the warning to “take time to be careful – now.”

Read more about the timeline of events leading up to the Exxon Valdez oil spill.

2. A law for the birds

Birds killed as a result of oil from the Exxon Valdez spill.

Thanks to the Oil Pollution Act, federal and state agencies can more easily evaluate the full environmental impacts of oil spills — and then enact restoration to make up for that harm. (Exxon Valdez Oil Spill Trustee Council)

Photos of oil-soaked birds and other wildlife in Prince William Sound reinforced just how inadequate the patchwork of existing federal, state, and local laws were at preventing or addressing the Exxon Valdez oil spill.

While lawmakers took nearly a year and a half—and a few more oil spills—to pass the Oil Pollution Act of 1990, this landmark legislation was without a doubt inspired by that major oil spill. (After all, the law specifically “bars from Prince William Sound any tank vessels that have spilled over 1,000,000 gallons of oil into the marine environment after March 22, 1989.” In other words, the Exxon Valdez.) In the years since it passed, this law has made huge strides in improving oil spill prevention, cleanup, liability, and restoration.

3.  The end of single-hull tankers

People observe a large tanker with a huge gash in its hull in dry dock.

Evidence of the success of double-hull tankers: The Norwegian tanker SKS Satilla collided with a submerged oil rig in the Gulf of Mexico in 2009 and despite this damage, did not spill any oil. (Texas General Land Office)

This image of a damaged ship is not showing the T/V Exxon Valdez, and that is precisely the point. The Exxon Valdez was an oil tanker with a single hull, which meant that when it hit ground, there was only one layer of metal for the rocks to tear through and release its tanks of oil.

But this 2009 photo shows the Norwegian tanker SKS Satilla after it sustained a major gash in its double-sided hull — and didn’t spill a drop of oil. Thanks to the Oil Pollution Act of 1990, all new tankers and tank-barges were required to be built with double hulls to reduce the chance of another Exxon Valdez situation. January 1, 2015 was the final deadline for phasing out single-hull tankers in U.S. waters.

 4. Oiled otters and angry kids

Policymakers weren’t the only ones to take note and take action in the wake of the Exxon Valdez oil spill. Second grader Kelli Middlestead of the Franklin School in Burlingame, California, was quite upset that the oil spill was having such devastating effects on one of her favorite animals: sea otters. So, on April 13, 1989, she wrote and illustrated a letter to Walter Stieglitz, Alaskan Regional Director of the U.S. Fish and Wildlife Service, to let him know she felt that the oil spill was “killing nature.”

Indeed, sea otters in Prince William Sound weren’t declared recovered from the Exxon Valdez oil spill until 2013. Other species still haven’t recovered and in some sheltered beaches below the surface, you can still find pockets of oil.

5. Oil and killer whales do mix (unfortunately)

Killer whales swimming alongside boats skimming oil from the Exxon Valdez oil spill.

Killer whales swimming in Prince William Sound alongside boats skimming oil from the Exxon Valdez oil spill (State of Alaska, Dan Lawn).

One of the species that has yet to recover after the Exxon Valdez oil spill is the killer whale, or orca. Before this oil spill, scientists and oil spill experts thought that these marine mammals were able to detect and avoid oil spills. That is, until two killer whale pods were spotted swimming near or through oil from this spill. One of them, a group nicknamed the “AT1 Transients” which feed primarily on marine mammals, suffered an abrupt 40% drop in population during the 18 months following the oil spill.

The second group of affected killer whales, the fish-eating “AB Pod Residents,” lost 33% of their population, and while they have started to rebound, the transients are listed as a “depleted stock” under the Marine Mammal Protection Act and may have as few as seven individuals remaining, down from a stable population of at least 22 in the 1980s.

Building on the lessons of the Exxon Valdez and Deepwater Horizon oil spills, NOAA has developed an emergency plan for keeping the endangered Southern Resident killer whale populations of Washington and British Columbia away from potential oil spills.

6. Tuna troubles

Top: A normal young yellowfin tuna. Bottom: A deformed yellowfin tuna exposed to oil during development.

A normal yellowfin tuna larva (top), and a larva exposed to Deepwater Horizon crude oil during development (bottom). The oil-exposed larva shows a suite of abnormalities including excess fluid building up around the heart due to heart failure and poor growth of fins and eyes. (NOAA)

How does crude oil affect fish populations? In the decades since the Exxon Valdez spill, teams of scientists have been studying the long-term effects of oil on fish such as herring, pink salmon, and tuna. In the first couple years after this spill, they found that oil was in fact toxic to developing fish, curving their spines, reducing the size of their eyes and jaws, and building up fluid around their hearts.

As part of this rich research tradition begun after the Exxon Valdez spill, NOAA scientists helped uncover the precise mechanisms for how this happens after the Deepwater Horizon oil spill in 2010. The photo here shows both a normal yellowfin tuna larva not long after hatching (top) and a larva exposed to Deepwater Horizon crude oil as it developed in the egg (bottom).

The oil-exposed larva exhibits a suite of abnormalities, showing how toxic chemicals in oil such as polycyclic aromatic hydrocarbons (PAHs) can affect the embryonic heart. By altering the embryonic heartbeat, exposure to oil can transform the shape of the heart, with implications for how well the fish can swim and survive as an adult.

7. Caught between a rock and a hard place

Mearns Rock boulder in 2003.

The boulder nicknamed “Mearns Rock,” located in the southwest corner of Prince William Sound, Alaska, was coated in oil which was not cleaned off after the 1989 Exxon Valdez oil spill. This image was taken in 2003. (NOAA)

Not all impacts from an oil spill are as easy to see as deformed fish hearts. As NOAA scientists Alan Mearns and Gary Shigenaka have learned since 1989, picking out those impacts from the noisy background levels of variability in the natural environment become even harder when the global climate and ocean are undergoing unprecedented change as well.

Mearns, for example, has been monitoring the boom and bust cycles of marine life on a large boulder—nicknamed “Mearns Rock”—that was oiled but not cleaned after the Exxon Valdez oil spill. What he and Shigenaka have observed on that rock and elsewhere in Prince William Sound has revealed large natural swings in the numbers of mussels, seaweeds, and barnacles, changes which are unrelated to the oil spill as they were occurring even in areas untouched by the spill.

Read more about how these scientists are exploring these challenges and a report on NOAA’s involvement in the wake of this spill.

8. A game culture

A view of part of the board game “On the Rocks: The Great Alaska Oil Spill” with a map of Prince William Sound.

The game “On the Rocks: The Great Alaska Oil Spill” challenges players to clean all 200 miles of shoreline oiled by the Exxon Valdez — and do so with limits on time and money. (Credit: Alaska Resources Library and Information Services, ARLIS)

Just as the Exxon Valdez oil spill touched approximately 200 miles of remote and rugged Alaskan shoreline, this spill also touched the hearts and minds of people far from the spill. References to it permeated mainstream American culture in surprising ways, inspiring a cookbook, a movie, a play, music, books, poetry, and even a board game.

That’s right, a bartender from Valdez, Alaska, produced the board game “On the Rocks: The Great Alaska Oil Spill” as a result of his experience employed in spill cleanup. Players vied to be the first to wash all 200 miles of oiled shoreline without running out of time or money.

9. Carrying a piece of the ship

The rusted and nondescript piece of steel on the left was a piece of the tanker Exxon Valdez, recovered by the salvage crew in 1989 and given to NOAA marine biologist Gary Shigenaka. It was the beginning of his collection of Exxon Valdez artifacts and remains the item with the biggest personal value to him. The piece of metal on the right, inscribed with "On the rocks," is also metal from the ship but was purchased on eBay.

The rusted and nondescript piece of steel on the left was a piece of the tanker Exxon Valdez, recovered by the salvage crew in 1989 and given to NOAA marine biologist Gary Shigenaka. It was the beginning of his collection of Exxon Valdez artifacts and remains the item with the biggest personal value to him. The piece of metal on the right, inscribed with “On the rocks,” is also metal from the ship but was purchased on eBay. (NOAA)

One NOAA scientist in particular, Gary Shigenaka, who kicked off his career working on the Exxon Valdez oil spill, was personally touched by this spill as well. After receiving a small chunk of metal from the ship’s salvage, Shigenaka began amassing a collection of Exxon Valdez–related memorabilia, ranging from a highball glass commemorating the ship’s launch in 1986 (ironic considering the questions surrounding its captain being intoxicated the night of the accident) to the front page of the local paper the day of the spill.

See more photos of his collection.

10. The infamous ship’s fate

Exxon Valdez/Exxon Mediterranean/Sea River Mediterranean/S/R Mediterranean/Mediterranean/Dong Fang Ocean/Oriental Nicety being dismantled on the beach of Alang, India, 2012.

Exxon Valdez/Exxon Mediterranean/Sea River Mediterranean/S/R Mediterranean/Mediterranean/Dong Fang Ocean/Oriental Nicety being dismantled in Alang, India, 2012. Photo by ToxicsWatch Alliance.

After causing the largest-to-date oil spill in U.S. waters, what ever happened to the ill-fated Exxon Valdez ship? It limped back for repairs to San Diego Bay where it was built, but by the time it was sea-ready again, the ship had been banned from Prince William Sound by the Oil Pollution Act and would instead be reassigned to the Mediterranean and Middle East and renamed accordingly, the Exxon Mediterranean.

But a series of new names and bad luck continued to follow this ship, until it was finally sold for scrap in 2011. Under its final name, Oriental Nicety, it was intentionally grounded at the infamous shipbreaking beaches of Alang, Gujarat, India, in 2012 and dismantled in its final resting place 23 years after the Exxon Valdez ran aground half a world away.


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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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How Do You Keep Killer Whales Away From an Oil Spill?

This is a guest post by Lynne Barre of NOAA Fisheries.

Two killer whales (orcas) breach in front a boat.

NOAA developed an oil spill response plan for killer whales that includes three main techniques to deploy quickly to keep these endangered animals away from a spill. (NOAA)

I sleep better at night knowing that we have a plan in place to keep endangered Southern Resident killer whales away from an oil spill. Preventing oil spills is key, but since killer whales, also known as orcas, spend much of their time in the busy waters around Seattle, the San Juan Islands, and Vancouver, British Columbia, there is always a chance a spill could happen.

The Southern Residents are a small and social population of killer whales, so an oil spill could have major impacts on the entire population if they were in the wrong place at the wrong time.

We’ve learned from past experience with the 1989 Exxon Valdez oil spill that killer whales and other marine mammals don’t avoid oiled areas on their own and exposure to oil likely can affect their populations. New information on impacts from the 2010 Deepwater Horizon oil spill on bottlenose dolphins (a close relative of killer whales) gives us a better idea of how oil exposure can affect the health and reproduction of marine mammals.

Oil spills are a significant threat to the Southern Resident population, which totals less than 90 animals, and the 2008 recovery plan [PDF] calls for a response plan to protect them. We brought experts together in 2007 to help us identify tools and techniques to deter killer whales from oil and develop a response plan so that we’d be prepared in case a major oil spill does happen.

The Sound of Readiness

Killer whales are acoustic animals. They use sound to communicate with each other and find food through echolocation, a type of biosonar. Because sound is so important, using loud or annoying sounds is one way that we can try to keep the whales away from an area contaminated with oil. We brainstormed a variety of ideas based on experience with killer whales and other animals and evaluated a long list of ideas, including sounds, as well as more experimental approaches, such as underwater lights, air bubble curtains, and hoses.

After receiving lots of input and carefully evaluating each option, we developed an oil spill response plan for killer whales that includes three main techniques to deploy quickly if the whales are headed straight toward a spill. Helicopter hazing, banging pipes (oikomi pipes), and underwater firecrackers are on the short list of options. Here’s a little more about each approach:

  • Helicopters are often available to do surveillance of oil and look for animals when a spill occurs. By moving at certain altitudes toward the whales, a helicopter creates sound and disturbs the water’s surface, which can motivate or “haze” whales to move away from oiled areas.
  • Banging pipes, called oikomi pipes, are metal pipes about eight feet long which are lowered into the water and struck with a hammer to make a loud noise. These pipes have been used to drive or herd marine mammals. For killer whales, pipes were successfully used to help move several whales that were trapped in a freshwater lake in Alaska.
  • Underwater firecrackers can also be used to deter whales. These small explosives are called “seal bombs” because they were developed and can be used to keep seals and sea lions away [PDF] from fishing gear. These small charges were used in the 1960s and 1970s to help capture killer whales for public display in aquaria. Now we are using historical knowledge of the whales’ behavior during those captures to support conservation of the whales.

In addition, our plan includes strict safety instructions about how close to get and how to implement these deterrents in order to prevent injury of oil spill responders and the whales. In the case of an actual spill, the wildlife branch within the Incident Command (the official response team dealing with the spill, usually led by the Coast Guard) would direct qualified responders to implement the different techniques based on specific information about the oil and whales.

Planning in Practice

Several killer whales break the surface of Washington's Puget Sound.

Killer whales use sound to communicate with each other and find food through echolocation. That’s why NOAA’s plan for keeping these acoustic animals away from oil spills involves using sound as a deterrent. (NOAA)

After incorporating the killer whale response plan into our overall Northwest Area Contingency Plan for oil spills, I felt better but knew we still had some work to do.

Since finalizing the plan in 2009, we’ve been focused on securing equipment, learning more about the techniques, and practicing them during oil spill drills. Working with the U.S. Coast Guard and local hydrophone networks (which record underwater sound), we’ve flown helicopters over underwater microphones to record sound levels at different distances and altitudes.

With our partners at the Washington Department of Fish and Wildlife and the Island Oil Spill Association, we built several sets of banging pipes and have them strategically staged around Puget Sound. In 2013 we conducted a drill with our partners and several researchers to test banging pipes in the San Juan Islands. It takes practice to line up several small boats, coordinate the movement of the boats, and synchronize banging a set of the pipes to create a continuous wall of sound that will discourage whales from getting close to oil. We learned a few critical lessons to update our implementation plans and to incorporate into plans for future drills.

A large oil spill in Southern Resident killer whale habitat would be a nightmare. I’m so glad we have partners focused on preventing and preparing for oil spills, and it is good to know we have a plan to keep an oil spill from becoming a catastrophe for endangered killer whales. That knowledge helps me rest easier and focus on good news like the boom in killer whale calves born to mothers in Washington’s Puget Sound.

You can find more information on our killer whale response plan and our recovery program for Southern Resident killer whales.

Lynne Barre in front of icy waters and snowy cliffs.Lynne Barre is a Branch Chief for the Protected Resources Division of NOAA Fisheries West Coast Region. She is the Recovery Coordinator for Southern Resident killer whales and works on marine mammal and endangered species conservation and recovery.


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Helping a 7-year-old Oceanographer Study Oil Spills in Washington’s Waters

A young boy drops wooden yellow cards off the side of a boat into water.

Dropping the first round of drift cards off a boat in Washington’s San Juan Islands, a kindergartner kicked off his experiment to study oil spills. (Used with permission of Alek)

One spring day in 2014, a shy young boy sidled up to the booth I was standing at during an open house hosted at NOAA’s Seattle campus. His blond head just peaking over the table, this then-six-year-old, Alek, accompanied by his mom and younger sister, proceeded to ask how NOAA’s oil spill trajectory model, GNOME, works.

This was definitely not the question I was expecting from a child his age.

After he set an overflowing binder onto the table, Alek showed me the printed-out web pages describing our oil spill model and said he wanted to learn how to run the model himself. He was apparently planning a science project that would involve releasing “drift cards,” small biodegradable pieces of wood marked with identifying information, into Washington’s Salish Sea to simulate where spilled oil might travel along this heavily trafficked route for oil tankers.

Luckily, Chris Barker, one of our oceanographers who run this scientific model, was nearby and I introduced them.

But that wasn’t my last interaction with this precocious, young oceanographer-in-training. Alek later asked me to serve on his science advisory committee (something I wish my middle school science fair projects had the benefit of having). I was in the company of representatives from the University of Washington, Washington State Department of Ecology, and local environmental and marine organizations.

Over the next year or so, I would direct his occasional questions about oil spills, oceanography, and modeling to the scientists in NOAA’s Office of Response and Restoration.

Demystifying the Science of Oil Spills

A hand-drawn map of oil tankers traveling from Alaska to Washington, a thank-you note on a post-it, and a hand-written card asking for donations.

Alek did a lot of work learning about how oil tankers travel from Alaska to Washington waters and about the threat of oil spills. He even fund-raised to cover the cost of materials for his drift cards. (NOAA)

According to the Washington Department of Ecology, the waters of the Salish Sea saw more than 7,000 journeys by oil tankers traveling to and from six oil refineries along its coast in 2013. Alek’s project was focused on Rosario Strait, a narrow eastern route around Washington’s San Juan Islands in the Salish Sea. There, he would release 400 biodegradable drift cards into the marine waters, at both incoming and outgoing tides, and then track their movements over the next four months.

The scientific questions he was asking in the course of his project—such as where spilled oil would travel and how it might affect the environment—mirror the types of questions our scientists and oil spill experts ask and try to answer when we advise the U.S. Coast Guard during oil spills along the coast.

As Alek learned, multiple factors influence the path spilled oil might take on the ocean, such as the oil type, weather (especially winds), tides, currents, and the temperature and salinity of the water. He attempted to take some of these factors into account as he made his predictions about where his drift cards would end up after he released them and how they would get there.

As with other drift card studies, Alek relied on people finding and reporting his drift cards when they turned up along the coast. Each drift card was stamped with information about the study and information about how to report it.

NOAA has performed several drift card studies in areas such as Hawaii, California, and Florida. One such study took place after the December 1976 grounding of the M/V Argo Merchant near Nantucket Island, Massachusetts, and we later had some of those drift cards found as far away as Ireland and France.

A Learning Experience

A young boy in a life jacket holding a yellow wooden card and sitting on the edge of a boat.

Alek released 400 biodegradable drift cards near Washington’s San Juan Islands in the Salish Sea, at both incoming and outgoing tides, and tracked their movements to simulate an oil spill. (Used with permission of Alek)

Of course, any scientist, young or old, comes across a number of challenges and questions in the pursuit of knowledge. For Alek, that ranged from fundraising for supplies and partnering with an organization with a boat to examining tide tables to decide when and where to release the drift cards and learning how to use Google Earth to map and measure the drift cards’ paths.

Only a couple weeks after releasing them, Alek began to see reports of his drift cards turning up in the San Juan Islands and even Vancouver Island, Canada, with kayakers finding quite a few of them.

As Alek started to analyze his data, we tried to help him avoid overestimating the area of water and length of coastline potentially affected by the simulated oil spill. Once released, oil tends to spread out on the water surface and would end up in patches on the shoreline as well.

Another issue our oceanographer Amy MacFadyen pointed out to Alek was that “over time the oil is removed from the surface of the ocean (some evaporates, some is mixed into the water column, etc.). So, the sites that it took a long time for the drift cards to reach would likely see less impacts as the oil would be much more spread out and there would be less of it.”

During his project, Alek was particularly interested in examining the potential impacts of an oil spill on his favorite marine organism, the Southern Resident killer whales (orcas) that live year-round in the Salish Sea but which are endangered. He used publicly available information about their movements to estimate where the killer whales might have intersected the simulated oil (the drift cards) across the Salish Sea.

Originally, Alek had hoped to estimate how many killer whales might have died as a result of a hypothetical oil spill in this area, but determining the impacts—both deadly and otherwise—of oil on marine mammals is a complicated matter. As a result, we advised him that there is too much uncertainty and not enough data for him to venture a guess. Instead, he settled on showing the number of killer whales that might be at risk of swimming through areas of simulated oil—and hence the killer whales that could be at risk of being affected by oil.

Ocean Scientist in Training

Google Earth view of the differing paths Alek's two drift card releases traveled around Washington's San Juan Islands and Canada's Vancouver Island.

A Google Earth view of the differing paths Alek’s two drift card releases traveled around Washington’s San Juan Islands and Canada’s Vancouver Island. Red represents the paths of drift cards released on an outgoing tide and yellow, the paths of cards released on an incoming tide. (Used with permission of Alek)

“I’d like to congratulate him on a successful drift card experiment,” said MacFadyen. “His results clearly show some of the features of the ocean circulation in this region.”

In a touching note in his final report, Alek dedicated his study to several great ocean scientists and explorers who came before him, namely, Sylvia Earle, Jacques Cousteau, William Beebe, and Rachel Carson. He was also enthusiastic in his appreciation of our help: “Thank you very very much for all of your help! I love what you do at NOAA. Maybe someday I will be a NOAA scientist!”

If you’re interested in learning more about Alek’s study and his results, you can visit his website www.oilspillscience.org, where you also can view a video summary of his project.


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Why Is It So Hard to Count the Number of Animals Killed by Oil Spills?

Dead bird covered in oil next to spill containment boom on a beach.

Many animals directly killed by oil spills will never be found at all for a number of reasons. Even if people can find a dead animal carcass, it might be too decomposed to tell if oil killed it. (Department of Interior)

After an oil spill along the coast, the impacts might appear to be pretty obvious: oil on beaches, dead birds, oil-coated otters. When conducting a Natural Resource Damage Assessment, it’s our job to measure those environmental impacts and determine what kind of restoration—and how much—is needed to make up for those impacts.

But in general we don’t base those calculations solely on how many animals were observed dead on shorelines, because that would drastically underestimate the total number of animals killed by an oil spill.

Why?

Well, for starters, the length of shoreline where animals might wash up could be very long, isolated, or otherwise difficult to survey. For a large oil spill, imagine trying to study a place as expansive as the Gulf of Mexico. This body of water covers roughly 600,000 square miles and borders five states. Also, significant portions of the shore are wetlands with convoluted shorelines that make searching and finding animals much more difficult than on sandy beaches.

Let Me Count the Ways

Scientists records data on a dead dolphin on a beach.

Oil spills can have indirect effects that don’t necessarily kill animals and plants, at least, not right away, but those impacts can lead to death and health and reproductive problems months or years later. (Credit: Louisiana Department of Fisheries and Wildlife)

Trying to determine the total number of animals that died because of an oil spill offers multiple challenges. Quantifying these impacts to wildlife relies in part on people being able to find, record, and sometimes take samples of dead animal carcasses across an extended distance and length of time.

They then would need to tie those deaths to a particular oil spill, which is part of our responsibility as we assess the environmental harm after a spill. It’s also complicated by the fact that animals die every day for many reasons other than oil spills, due to changes in weather, food supplies, predation, background pollution, and disease.

This difficult undertaking has numerous limitations, and as a result, relying on counts of animal deaths alone can drastically underestimate the actual harm caused by a spill.

Graphic of oil spill in ocean near coast showing the multiple scenarios for the carcasses of animals killed by an oil spill. They include: Discovered carcasses (Of those carcasses that are found, most are too decomposed to determine the cause of death), remote strandings (Animals strand on remote shorelines that humans don't frequent), scavenging (Carcasses attract scavengers, such as sharks, birds, crabs, and others, that consume and remove evidence of dead animals), dying underwater (Some animals may die while underwater and disappear), decomposition (Hot weather causes carcasses to decay quickly in the water and on the shore), sinking (Carcasses may sink), and winds, currents, and distance from shore (These factors impact the movement of animals toward or away from shore).

The challenge of finding an animal that dies from an oil spill: Only a fraction of the turtles, dolphins, birds, fish, and other animals killed by an oil spill are ever found. (NOAA)

For example, even if people can find a dead animal carcass, it might be too decomposed to tell if oil killed it. But more likely are the scenarios where animals directly killed by oil will never be found at all because they:

  • Are eaten by predators or scavengers.
  • Die underwater.
  • Sink below the ocean surface.
  • Wash ashore in remote areas where people can’t or don’t often go.
  • Are carried out to the open ocean by winds and currents.
  • Decompose before people can observe them.
  • Are too tiny for people to easily observe after they die (e.g., young fish and crustaceans).

Late-Breaking Effects

To make things even more challenging, oil spills can have indirect effects that don’t outright kill animals and plants, at least, not right away. Dealing with exposure to oil can cause a number of damaging impacts, including lung disease (from inhaling oil vapors), stress hormone dysfunction, reduced growth, increased vulnerability to disease, heart failure and deformities in developing fish, and reproductive problems in animals such as dolphins and fish.

These types of effects can lead to other health impacts and sometimes eventually death, with the fallout felt across generations. Simply trying to count the number of dead animal carcasses found immediately after an oil spill would miss these deaths (or births that never happen) that can come months or even years afterward.

Seek and You May or May Not Find

Despite these challenges, it’s still useful to collect dead animal carcasses after an oil spill and use information gained from them to support other approaches for determining broader oil spill impacts.

One such approach takes into account several additional types of data, along with the observations of dead animals, to infer the likely true number of animals killed by an oil spill. These data include different animals’ estimated exposure to oil, health effects observed in laboratory and field studies, and basic information about animal behavior at different stages of life.

For instance, after the 2007 Cosco Busan oil spill in California’s San Francisco Bay, search teams recovered several thousand oiled birds, and additional studies were later performed to determine how many more dead birds were likely killed that were never seen or collected.

In one such study (known as a “Searcher Efficiency Study”), a study team randomly placed 107 real bird carcasses along San Francisco Bay shorelines over the course of three days, and teams were deployed to search for them and collect what they could find. It is surprisingly easy for searchers to miss dead birds on the beach since the animals blend in with other debris or beach wrack, can be hidden by small depressions, or be too far away to recognize.

Since the study team knew the actual number and locations of carcasses deployed for the study, the number that search teams collected provided a basis for calculating how many dead birds were likely missed by search teams during the actual Cosco Busan oil spill. This study determined that a two-person search team would find 68% of the dead bird carcasses on San Francisco Bay beaches.

More than a dozen other studies [PDF] were also performed after this oil spill, contributing additional data that went into the calculations of the total numbers and species of birds killed. Through this work, the actual number of birds killed by the spill was estimated to be 6,849, nearly two and a half times the number of birds actually collected during the Cosco Busan oil spill.

We commonly use several other methods to determine the magnitude of an oil spill’s effects on animals and plants, including studies of habitat changes, laboratory toxicity studies, and modeling.

Stay tuned because we plan to discuss these approaches more in-depth in the future. In the meantime, learn about the scientific processes we use to assess an oil spill’s environmental impacts at darrp.noaa.gov/science/our-scientific-process.


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Explore Oil Spill Data for Gulf of Mexico Marine Life With NOAA GIS Tools

In the wake of the Deepwater Horizon oil spill, the sheer amount of data scientists were gathering from the Gulf of Mexico was nearly overwhelming. Everything from water quality samples to the locations of oiled sea turtles to photos of dolphins swimming through oil—the list goes on for more than 13 million scientific records.

So, how would anyone even start to dig through all this scientific information? Fortunately, you don’t have to be a NOAA scientist to access, download, or even map it. We have been building tools to allow anyone to access this wealth of information on the Gulf of Mexico environment following the Deepwater Horizon oil spill.

We’re taking a look at two of our geographic information systems tools and how they help scientists, emergency responders, and the public navigate the oceans of environmental data collected since the 2010 Deepwater Horizon oil spill.

When it comes to mapping and understanding huge amounts of these data, we turn to our GIS-based tool, the Environmental Response Management Application, known as ERMA®. This online mapping tool is like a Swiss army knife for organizing data and information for planning and environmental emergencies, such as oil spills and hurricanes.

ERMA not only allows pollution responders to see real-time information, including weather information and ship locations, but also enables users to display years of data, revealing to us broader trends.

View of Environmental Response Management Application showing map of Gulf of Mexico with varying probabilities of oil presence and sea turtle oiling during the Deepwater Horizon oil spill with data source information.

In the “Layer” tab on the right side of the screen, you can choose which groups of data, or “layers,” to display in ERMA. Right click on a data layer, such as “Turtle Captures Probability of Oiling (NOAA) (PDARP),” and select “View metadata” to view more information about the data being shown. (NOAA)

For instance, say you want to know the likelihood of sea turtles being exposed to heavy oil during the Deepwater Horizon oil spill. ERMA enables you to see where sea turtles were spotted during aerial surveys or captured by researchers across the Gulf of Mexico between May and September 2010. At the same time, you can view data showing the probability that certain areas of the ocean surface were oiled (and for how long), all displayed on a single, interactive map.

View of Environmental Management Application map of Gulf of Mexico showing varying probabilities of oil presence and sea turtle exposure to oil during the Deepwater Horizon oil spill with map legend.

Clicking on the “Legend” tab on the right side of the screen shows you basic information about the data displayed in ERMA. Here, the red area represents portions of the Gulf of Mexico which had the highest likelihood of exposing marine life to oil. Triangles show sea turtle sightings and squares show sea turtle captures between May and September 2010. The color of the symbol indicates the likelihood of that sea turtle receiving heavy exposure to oil. (NOAA)

Perhaps you want to focus on where Atlantic bluefin tuna were traveling around the Gulf and where that overlaps with the oil spill’s footprint. Or compare coastal habitat restoration projects with the degree of oil different sections of shoreline experienced. ERMA gives you that access.

You can use ERMA Deepwater Gulf Response to find these data in a number of ways (including search) and choose which GIS “layers” of data to turn on and off in the map. To see the most recently added data, click on the “Recent Data” tab in the upper left of the map interface, or find data by browsing through the “Layers” tab on the right. Or look for data in special “bookmark views” on the lower right of the “Layers” tab to find data for a specific topic of interest.

Now, what if you not only want to see a map of the data, what if you also want to explore any trends in the data at a deeper level? Or download photos, videos, or scientific analyses of the data?

That’s where our data management tool DIVER comes in. This tool serves as a central repository for environmental impact data from the oil spill and was designed to help researchers share and find scientific information ranging from photos and field notes to sample data and analyses.

As Ocean Conservancy’s Elizabeth Fetherston put it:

Until recently, there was no real way to combine all of these disparate pixels of information into a coherent picture of, for instance, a day in the life of a sea turtle. DIVER, NOAA’s new website for Deepwater Horizon assessment data, gives us the tools to do just that.

Data information and integration systems like DIVER put all of that information in one place at one time, allowing you to look for causes and effects that you might not have ever known were there and then use that information to better manage species recovery. These data give us a new kind of power for protecting marine species.

One of the most important features of DIVER, called DIVER Explorer, is the powerful search function that allows you to narrow down the millions of data pieces to the precise set you’re seeking. You do it one step, or “filter,” at a time.

DIVER software dialog box showing how to build a query by workplan topic area for marine mammals studied during the Deepwater Horizon oil spill.

A view of the step-by-step process of building a “query,” or specialized search, in our DIVER tool for Deepwater Horizon oil spill environmental impact data. (NOAA)

For example, when you go to DIVER Explorer, click on “Guided Query” at the top and then “Start to Explore Data,” choose “By Workplan Topic Area,” hit “Next,” and finally select “Marine Mammals” before clicking “Run Query” to access information about scientific samples taken from marine mammals and turtles. You can view it on a map, in a table, or download the data to analyze yourself.

An even easier way to explore these data in DIVER, however, is by visiting https://www.doi.gov/deepwaterhorizon/adminrecord and scrolling down to and clicking on #5 Preassessment/Assessment (§§ 990.40 – 990.45; 990.51). This will reveal a list of various types of environmental impacts—to birds, sea floor habitat, marine mammals, etc.—which the federal government studied as part of the Deepwater Horizon oil spill’s Natural Resource Damage Assessment.

Say you’re interested in marine mammals, so you click on 5.6 Marine Mammal Injury and then 5.6.3 Data sets. You can then download and open the document “NOAA Marine Mammal data related to the Deepwater Horizon incident, available through systems such as DIVER and ERMA, or as direct downloads. (September 23, 2015).”

Under the section “Data Links,” you can choose from a variety of stored searches (or “queries”) in DIVER that will show you where and when, for example, bottlenose dolphins with satellite tags traveled after the spill (tip: zoom in to view this data on the map)—along with photographs to go with it (tip: click on the “Photos” tab under the map to browse).

Map view of DIVER software map showing where tagged dolphins swam in the Gulf of Mexico after the Deepwater Horizon oil spill.

A map view of DIVER shows where tagged dolphins traveled along the Gulf Coast, showing two populations that stayed in their home bases of Barataria Bay and Mississippi Sound. (NOAA)

This can tell us key information, such as the fact that certain populations of dolphins stay in the same areas along the coast, meaning they don’t travel far from home. We can also look at data about whether those dolphin homes were exposed to a lot of oil, which would suggest that the dolphins that lived there likely were exposed to oil again and again.

Both of these tools allow us to work with incredible amounts of data and see their stories brought to life through the power of geographic information systems. So, go ahead and start exploring!


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Births Down and Deaths Up in Gulf Dolphins Affected by Deepwater Horizon Oil Spill

A mother bottlenose dolphin pushes her dead newborn calf at the water's surface.

Dolphin Y01 pushes a dead calf through the waters of Barataria Bay, Louisiana, in March 2013. This behavior is sometimes observed in female dolphins when their newborn calf does not survive. Barataria Bay dolphins have seen a disturbingly low rate of reproductive success in the wake of the Deepwater Horizon oil spill. (Louisiana Department of Wildlife and Fisheries)

In August of 2011, a team of independent and government scientists evaluating the health of bottlenose dolphins in Louisiana’s Barataria Bay gave dolphin Y35 a good health outlook.

Based on the ultrasound, she was in the early stages of pregnancy, but unlike many of the other dolphins examined that summer day, Y35 was in pretty good shape. She wasn’t extremely underweight or suffering from moderate-to-severe lung disease, conditions connected to exposure to Deepwater Horizon oil in the heavily impacted Barataria Bay.

Veterinarians did note, however, that she had alarmingly low levels of important stress hormones responsible for behaviors such as the fight-or-flight response. Normal levels of these hormones help animals cope with stressful situations. This rare condition—known as hypoadrenocorticism—had never been reported before in dolphins, which is why it was not used for Y35 and the other dolphins’ health prognoses.

Less than six months later, researchers spotted Y35 for the last time. It was only 16 days before her expected due date. She and her calf are now both presumed dead, a disturbingly common trend among the bottlenose dolphins that call Barataria Bay their year-round home.

This trend of reproductive failure and death in Gulf dolphins over five years of monitoring after the 2010 Deepwater Horizon oil spill is outlined in a November 2015 study led by NOAA and published in the peer-reviewed journal Proceedings of the Royal Society.

Of the 10 Barataria Bay dolphins confirmed to be pregnant during the 2011 health assessment, only two successfully gave birth to calves that have survived. This unusually low rate of reproductive success—only 20%—stands in contrast to the 83% success rate in the generally healthier dolphins being studied in Florida’s Sarasota Bay, an area not affected by Deepwater Horizon oil.

Baby Bump in Failed Pregnancies

While hypoadrenocorticism had not been documented previously in dolphins, it has been found in humans. In human mothers with this condition, pregnancy and birth—stressful and risky enough conditions on their own—can be life-threatening for both mother and child when the condition is left untreated. Wild dolphins with this condition would be in a similar situation.

Mink exposed to oil in an experiment ended up exhibiting very low levels of stress hormones, while sea otters exposed to the Exxon Valdez oil spill experienced high rates of failed pregnancies and pup death. These cases are akin to what scientists have observed in the dolphins of Barataria Bay after the Deepwater Horizon oil spill.

Among the pregnant dolphins being monitored in this study, at least two lost their calves before giving birth. Veterinarians confirmed with ultrasound that one of these dolphins, Y31, was carrying a dead calf in utero during her 2011 exam. Another pregnant dolphin, Y01, did not successfully give birth in 2012, and was then seen pushing a dead newborn calf in 2013. Given that dolphins have a gestation of over 12 months, this means Y01 had two failed pregnancies in a row.

The other five dolphins to lose their calves after the Deepwater Horizon oil spill, excluding Y35, survived pregnancy themselves but were seen again and again in the months after their due dates without any young. Dolphin calves stick close to their mothers’ sides in the first two or three months after birth, indicating that these pregnant dolphins also had calves that did not survive.

At least half of the dolphins with failed pregnancies also suffered from moderate-to-severe lung disease, a symptom associated with exposure to petroleum products. The only two dolphins to give birth to healthy calves had relatively minor lung conditions.

Survival of the Least Oiled

Dolphin Y35 wasn’t the only one of the 32 dolphins being monitored in Barataria Bay to disappear in the months following her 2011 examination. Three others were never sighted again in the 15 straight surveys tracking these dolphins. Or rather, they were never seen again alive. One of them, Y12, was a 16-year-old adult male whose emaciated carcass washed up in Louisiana only a few weeks before the pregnant Y35 was last seen. In fact, the number of dolphins washing up dead in Barataria Bay from August 2010 through 2011 was the highest ever recorded for that area.

Survival rate in this group of dolphins was estimated at only 86%, down from the 95-96% survival seen in dolphin populations not in contact with Deepwater Horizon oil. The marshy maze of Barataria Bay falls squarely inside the footprint of the Deepwater Horizon oil spill, and its dolphins and others along the northern Gulf Coast have repeatedly been found to be sick and dying in historically high numbers. Considering how deadly this oil spill has been for Gulf bottlenose dolphins and their young, researchers expect recovery for these marine mammals to be a long time coming.

Watch an updated video of the researchers as they temporarily catch and give health exams to some of the dolphins in Barataria Bay, Louisiana, in August of 2011 and read a 2013 Q&A with two of the NOAA researchers involved in these studies:

This study was conducted under the Natural Resource Damage Assessment for the Deepwater Horizon oil spill. These results are included in the injury assessment documented in the Draft Programmatic Assessment and Restoration Plan that is currently out for public comment. We will accept comments on the plan through December 4, 2015.

This research was conducted under the authority of Scientific Research Permit nos. 779-1633 and 932-1905/MA-009526 issued by NOAA’s National Marine Fisheries Service pursuant to the U.S. Marine Mammal Protection Act.