Starting next year, oil and gas industry ships could be crisscrossing the Atlantic coastline, firing off seismic air guns every 12 seconds at a noise level that would rupture a human eardrum.
But the underwater blasts will remain imperceptible to people, instead affecting marine mammals and fish in largely unknown ways.
The noise could mask the calls of whales, cause mammals to leave feeding areas and interrupt breeding. It might damage whales’ hearing, in the short term and perhaps even permanently. Fish and sea turtles might flee. Larvae may die.
But the seismic surveys form a crucial part of the Obama administration’s plan to open up Atlantic waters to drilling. The Bureau of Ocean Energy Management (BOEM) has proposed selling leases in its 2017-2022 plan, and oil and gas companies want to use air guns to find untapped mineral deposits and decide where to drill.
The upshot: Federal officials will have to make a decision on seismic surveys before the science is set, weighing the precautionary principle against mounting pressure to open new areas to development.
A recent congressional hearing laid bare the politics, with House Republicans accusing the National Oceanic and Atmospheric Administration of dragging its feet in approving permits for seismic surveys to injure and harass marine mammals (E&E Daily, July 15). In the lawmakers’ view, the safety of seismic surveys is evident from their use around the world.
"Seismic surveying can be conducted safely, causing no harm to marine mammals, so why should it take so long to get a permit?" Rep. Doug Lamborn (R-Colo.) said. "I have yet to hear a reasonable answer to this question."
Many scientists, however, say marine mammals — and particularly whales — are almost certainly affected by the sound. Though research is limited, companies that use seismic testing must get approval from NOAA’s National Marine Fisheries Service (NMFS) because of the potential for injuries and harassment to marine mammals.
NOAA in July released applications from four companies for such permits in the Atlantic and hopes to publish proposed authorizations in September and finalize them by the end of the year (Greenwire, July 28).
Until now, most seismic activity has occurred in the Gulf of Mexico and the Arctic. Alaska’s Cook Inlet, for example, is host to two or three seismic surveys a year. A recently issued permit from NOAA allows one company to harass endangered beluga whales there up to 30 times in a year, meaning the agency believes the sound could cause 10 percent of the whale’s population to change its behavior.
How whales specifically react is frustratingly unclear. NOAA has listed numerous possibilities: changing duration of dives, switching directions, reducing or increasing vocal activities, and stopping feeding activities, among others.
Amy Scholik-Schlomer, an acoustics expert from NMFS’s Office of Protected Resources, said the size of a seismic air gun array makes a difference. Companies use all types of seismic surveys, with varying levels of sound and time between the blasts.
Where an animal is during the blast also plays into how it’s affected. Experts are fairly confident about how a blast would affect an animal right next to it; depending on the array, the sound can be far louder than a jet engine, causing direct physical injury.
But most whales and other marine mammals are not that close. Instead, they hear the sound as it travels from the source, where it stretches into longer and quieter signals.
"It’s fairly new science," Scholik-Schlomer said. "We’ve probably learned a lot in the last decade or so, but there’s still a lot of unanswered questions on the effect of noise in general."
Impacts also depend on context. If a whale is feeding, for example, it might stop and thus suffer the effects of that lost dinner. But if it is just passing through, researchers might not witness any effect.
Scholik-Schlomer emphasized that scientists have data showing effects. But existing studies have so far focused on a "snapshot in time and space." In other words, researchers know some of the scenes but haven’t seen the feature-length film.
"The challenging part is understanding what a change in migration pattern or a change in avoidance means to a particular individual in the long term and what that means to the species in a population-level effect," she said. "If they alter their migration pattern for a little while, is that a big deal or not? That’s the harder question."
A ‘significant threat’ or no threat at all?
When it comes to introducing seismic surveys along the country’s Atlantic coast, predicting the effects becomes even more difficult.
The coast is loud, partly due to the constant rumbling of ships. And though the oil and gas industry hasn’t used seismic surveys there since the 1980s, researchers occasionally use the same technology. Over the past year, a project involving the U.S. Geological Survey and the National Science Foundation used seismic air guns to map sediment thickness on the sea floor.
Proponents of offshore drilling argue that oil and gas seismic surveys are a drop in a proverbial bucket. The ocean is filled with sounds, they say, both natural and human-made.
At a House Natural Resources Committee hearing, a scientist with the International Association of Geophysical Contractors asserted that marine mammals are perhaps bothered, but not harmed, by the booms of seismic air guns.
"There is no doubt that seismic surveys — as do many natural sounds — get the attention of animals, alter their behavior in some way, that’s a normal part of life," Robert Gisiner, the association’s director of marine environment, told lawmakers. "We’re talking about when that disturbance becomes something that is more than they can accommodate in their normal course of life, and we haven’t seen that yet. We’ll continue to look for it, but we haven’t seen it yet."
Gisiner’s comments hit the crux of the debate over seismic surveys: Does the lack of proven, population-level effects mean they don’t exist? Or does it mean that science just hasn’t caught up yet?
BOEM has asserted that there is "no documented scientific evidence" that air guns adversely affect marine animal populations. In 2014, when the bureau announced its final decision to allow Atlantic seismic surveys, the agency’s CEO released a newsletter to ensure the public was "getting the facts right."
"BOEM has the legal responsibility to protect marine species and ecosystems from harm by the energy exploration and development which we regulate, and that is a responsibility which I embrace without reservation," William Brown wrote, before emphasizing that the bureau put mitigation measures in place to prevent harm.
But earlier this year, marine scientists from top universities disputed that characterization. In a letter to President Obama, they asserted that seismic surveys along the Atlantic coast pose a "significant threat to marine life," likely leaving an "enormous environmental footprint."
The scientists hailed from Cornell University, Duke University, the New England Aquarium and numerous other institutions. Their view: The Interior Department can’t mitigate the effect of seismic surveys because no one knows the extent to which air guns affect marine life (Greenwire, March 5).
"The Interior Department’s decision to authorize seismic surveys along the Atlantic coast is based on the premise that these activities would have only a negligible impact on marine species and populations," they wrote. "Our expert assessment is that the Department’s premise is not supported by the best available science."
Federal agencies clash
Among those who signed the letter was Andrew Read, a professor of marine biology at Duke whom Obama has nominated to head the Marine Mammal Commission (MMC) (E&E Daily, March 19).
The MMC has voiced some concerns about the number and scope of the proposed seismic surveys. The independent federal agency — which advises other agencies on protecting marine mammals — believes the government should have "good baseline information" on marine life along the Atlantic before seismic surveys begin, said Vicki Cornish, the commission’s energy policy analyst.
Such information would include the type and abundance of species, as well as hot spots for feeding and reproduction. Experts could in turn use that data to identify important areas that seismic surveys should avoid during certain times of the year or altogether.
The government would also have a baseline for further research. Once the seismic surveys began, researchers could compare the before-and-after — a perspective that has so far been out of reach. Seismic surveys in the Arctic and the Gulf of Mexico began without a comprehensive study of marine life in those areas.
Brandon Southall, the former director of NOAA’s Ocean Acoustics Program, advocated a similar idea in a recent interview. While scientists have studied coastal areas along the East Coast, he said, they know much less about the offshore areas where seismic surveys, and eventually drilling, would occur.
Without knowing what’s going on in the Atlantic now, he said, scientists may not be able to discern the behavioral changes that could significantly affect a species.
Southall led a group of experts to produce a 2007 paper, used often by NOAA, that recommends noise exposure criteria. He said he didn’t object to allowing seismic surveys; after all, such surveys undergo far more scrutiny than shipping.
But first, he said, the government should complete a three-to-five-year multidisciplinary study on the area.
"Just because we’ve blown it on shipping doesn’t mean we shouldn’t take a more informed response to allowing a major change in the environment," said Southall, now president of Southall Environmental Associates Inc. "I don’t think anybody would deny having these kinds of surveys, and the activities that would potentially follow them wouldn’t constitute a relatively major disturbance, at least locally."
Barring such a study, the MMC has asked Interior’s BOEM to consider limiting the number of seismic surveys. The eight companies that have applied for permits would overlap, looking in the same areas for mineral resources.
The MMC’s suggestion: consolidate surveys, so marine mammals are exposed to less sound overall.
"We understand that there are economics and market forces," the MMC’s Cornish said. "The bureau has noted that each applicant has a fair bite at the apple, but that’s a pretty precious apple to bite from, and if we could minimize the number of bites, it would be better for marine mammals in the long run."
But BOEM says the role is beyond its mission. In its final environmental impact statement (EIS) on allowing Atlantic seismic surveys — released last year — the agency points out that "consolidating and coordinating surveys would require the creation of another untested series of regulatory controls and reviews."
"As a leasing and permitting agency that administers Federal lands, BOEM acts upon requests to use those Federal lands; BOEM does not direct the actions of operators in the private sector or compel business decisions," BOEM officials wrote in the EIS.
Buzzing and moaning
Conservationists are particularly concerned about North Atlantic right whales, so named because their slow speed and tendency to swim at the surface made them easy targets for whalers. In the early 1900s, they were the "right" whale to hunt.
Today, the baleen whales number fewer than 500, with most, if not all, belonging to the "western" population that spends summer and autumn in Northeast waters and winters near Georgia and Florida. The eastern population — or those that migrate along the European coast — may already be extinct.
Like other whales, they communicate with sounds. To the human ear, their calls are diverse: They buzz, moan, warble, scream. The males produce a gunshot-like sound, thought to play a role in reproduction.
The whales already live in an underwater world filled with the noises of shipping. But on Sept. 11, 2001, much of that noise suddenly disappeared, as ship traffic decreased in the aftermath of the terrorist attacks.
Researchers in 2012 analyzed acoustic recordings from before and after the tragedy, as well as results from a study of the whales’ hormone levels. Their finding: North Atlantic right whales in Canada’s Bay of Fundy had lower stress-related hormone levels during the Sept. 11 pause in shipping.
Seismic surveys are a different sound, much louder but also with 10-to-20-second breaks. No one knows for sure how whales will react to that addition.
"You’re mucking with the communication system of animals that rely on sounds as their primary communication modality," said Douglas Nowacek, a marine science professor at Duke who has spent much of his career studying how noise affects marine mammals. "We don’t have any appreciation for how subtle these things are in the ocean."
A few studies have shown some effects on other baleen whales. A 2013 study in Marine Mammal Science found that calls from bowhead whales in Alaska’s Beaufort Sea decreased at the onset on air gun use, at sites near those air guns. Another from 2012 — published in Biological Conservation — indicated that fin whales left an area after the beginning of seismic activity and then stayed away beyond the 10-day survey. And a 2014 study in PLOS ONE indicated that seismic surveys off the coast of northern Angola decreased the singing activity of humpback whales.
The seismic surveys in the Atlantic — if approved — would run continuously for months, potentially 24 hours a day, seven days a week. Spectrum Geo Inc., for example, plans to use two survey vessels for 12 months, each with an array of 32 air guns.
BOEM has designated an area for seismic surveys that stretches from Delaware Bay to just south of Cape Canaveral, Fla. Companies will not be allowed to conduct surveys within the North Atlantic right whale’s critical habitat from Nov. 15 to April 15, when the whales are present and breeding.
The bureau has also set up other protections, such as sound restrictions on the boundaries of the whale’s critical habitat and additional closures along the coast during certain times of year.
Environmental groups say such closures are not broad enough. In 2013, research from Cornell’s Bioacoustics Research Program indicated right whales might migrate farther off Virginia’s shores than previously assumed (E&ENews PM, Dec. 19, 2013). Those whales would be beyond the 20-mile buffer from shore that BOEM plans to close part of the year.
But before operating in any area, companies need to obtain incidental harassment authorizations from NOAA — and those will come with additional mitigation measures.
For past surveys in the Arctic and the Gulf of Mexico, NOAA has required that a trained observer be on board survey vessels to spot marine mammals. Once the mammals are spotted within a certain distance, vessels must stop firing the air guns. Most surveys in the Atlantic would have two observers, according to BOEM’s EIS.
But that has its limits, according to scientists and environmentalists. In addition to human error, it can be difficult to detect animals that may be far under the surface.
"I’ve worked as a marine mammal observer on scientific cruises before," Ingrid Biedron, a marine scientist at Oceana, said in a recent interview. "It’s hard to see whales if you don’t have optimum conditions — if it’s foggy or it’s choppy or if it’s dark and night vision is limited."
The availability of passive acoustic monitoring has allayed some concerns. Such devices are used to detect mammals underwater when they make noise, alerting ships to their presence even if they can’t be seen from above.
For the seismic survey in Cook Inlet, for example, NOAA requires the company to use passive acoustic monitoring while it ramps up the air guns and from sunset to sunrise.
But when animals are silent, they go undetected.
A guessing game
Oceana thinks the risk is too great.
Last year, the environmental group kicked off a grass-roots campaign, urging local governments to protest seismic surveys off their shores. More than 70 towns, cities and counties along the East Coast have passed resolutions opposing or expressing concern over the surveys or the offshore drilling expected in the coming years, according to Oceana.
The group points to BOEM’s own estimates to build its case against the surveys. At face value, the effects can look staggering: BOEM estimates that the surveys could injure 138,000 marine animals and disturb 13 million.
What that means in reality is far less clear. BOEM has asserted that the numbers are misleading because they don’t consider mitigation measures. And NOAA routinely approves seismic surveys as having a "negligible impact" on marine mammals, even when incidental harassment authorizations allow disturbances on thousands of animals.
Injuries and disturbances for each species also vary drastically. Spectrum Geo, one of the companies that wants to operate in the Atlantic, estimates its air guns would injure marine mammals 32,000 times — but only 14 North Atlantic right whales.
When reviewing such applications, NOAA uses two sound thresholds to determine injuries: one for cetaceans such as whales, and another for pinnipeds, or seals. The agency is in the middle of updating those, recently releasing draft guidance that takes into account the difference of sound sources and the hearing ability of different mammals.
But NOAA is still working on guidance addressing behavioral response — the effect that worries scientists the most. The agency currently estimates how many mammals will be disturbed by using a sound threshold; if the sound registers lower than that, it is assumed that animals don’t respond.
Duke’s Nowacek has argued that the threshold is "overly simple, artificially rigid and hopelessly outdated." But a more nuanced system for determining impacts may not come until after Atlantic marine life hears its first air gun in 30 years.
Southall, the former NOAA official, said that lack of data leaves risks.
"The focus on killing animals with these kinds of things is misplaced. It misses the point. From lab work and the monitoring that’s been done, it seems that these animals are built to tolerate pretty loud sounds," Southall said. "I think the thing that we run the risk of happening would be not doing a good job of understanding the basics of ecological and behavioral effects."