Study: Declines in air pollutants had direct positive effect on children’s health

Pump Handle - March 17, 2015

In the first study of its kind, researchers have found that improved air quality in southern California had a direct effect on children’s respiratory health. The findings point to the effectiveness of smart public health policy — in other words, even as southern California experienced increases in traffic and commerce, aggressive air pollution policies resulted in cleaner air and healthier kids.

Published earlier this month in the New England Journal of Medicine, the study concluded that air quality improvements in the southern California communities studied were associated with significantly positive effects on lung function growth in children. In even simpler terms, as pollution declined, children’s lungs actually grew stronger.

“The most surprising part was the magnitude of improvements over a relatively short period of time,” study co-author W. James Gauderman, professor of preventive medicine at the University of Southern California (USC) Keck School of Medicine, told me. “It’s really an amazing turnaround to have had these improvements even with increased sources of emissions.”

To conduct the study, researchers measured annual lung function among more than 2,100 children in three different cohorts and during three separate time periods: 1994-1998, 1997-2001 and 2007-2011. The children, who were 11 years old at the beginning of each time period and 15 years old at the end, hailed from the communities of Long Beach, Mira Loma, Riverside, San Dimas and Upland. Lung function growth over the four-year intervals was measured via forced expiratory volume in one second (also known as FEV and defined as the amount of air exhaled in the first second of a forced exhalation) and forced vital capacity (known as FVC and defined as the amount of air exhaled after taking the deepest breath possible). Pollutant levels were gleaned from data collected via outdoor monitoring stations.

Researchers found that lung growth between ages 11 and 15 was more than 10 percent greater for the children exposed to lower levels of nitrogen dioxide from 2007 to 2011 compared to children breathing higher levels of the air pollutant from 1994 to 1998. Also, the percentage of 15-year-old children with abnormally low lung function dropped from about 8 percent within the 1994-1998 study cohort to 6.3 percent in the 1997-2001 cohort to 3.6 percent in the 2007-2011 cohort. Those improvements coincided with the enactment of health-driven air quality policies and vehicle emissions standards, which have produced dramatic air quality results. The study found that combined exposure to two pollutants harmful to human health — nitrogen dioxide and particulate matter less than 2.5 microns (PM2.5) — declined by about 40 percent for the 2007-2011 cohort when compared to the 1994-1998 cohort.

What’s even more impressive is that the positive gains in children’s lung function were documented even after researchers adjusted for confounding variables, such as tobacco smoke exposure, health insurance status, parental educational attainment, asthma and indoor pollutants, such as pets and mold. Indeed, both children with and without asthma experienced better lung function growth as air quality improved. Study authors Gauderman, Robert Urman, Edward Avol, Kiros Berhane, Rob McConnell, Edward Rappaport, Roger Chang, Fred Lurmann and Frank Gilliland wrote:

This study shows an association between secular improvements in air quality in southern California and measurable improvements in lung-function development in children. Improved lung function was most strongly associated with lower levels of particulate pollution (PM2.5 and PM10) and nitrogen dioxide. These associations were observed in boys and girls, Hispanic white and non-Hispanic white children, and children with asthma and children without asthma, which suggests that all children have the potential to benefit from improvements in air quality.

Gauderman told me that while we’ve known for some time that breathing dirty air is bad for kids via studies that compare polluted and unpolluted communities, this is the first study to start with a polluted community and follows its young residents over time as air pollutants decline. He noted that the study caught kids at a time of rapid lung development. By age 15, lung function development in girls is about finished and boys’ development is slowing down, Gauderman said, and so by the time adolescents transition into adulthood, they have the lungs they’ll have for life. That’s why it’s so important to encourage respiratory health in the early years, as reduced lung capacity and function is a primary risk factor for lung disease in adulthood as well as reduced lifespan. In other words, kids who grow up breathing cleaner air may have a jumpstart on becoming healthier adults, he said.

Gauderman added that among the pollutants studied, declines in nitrogen dioxide and particulate matter, which are products of fuel combustion, were most associated with improvements in kids’ health. And because such pollutants are common in urban areas, Gauderman said similar health improvements could be expected in other communities that pursue stricter clean air policies.

“In an urban environment, you obviously can’t make decisions about breathing the air or not, so it really does take societal decisions to change those exposures,” Gauderman told me. “Given the projections we have for even more cars, more people and more economic activity, we definitely do not want to lose the gains we’ve made. It’s going to take continued vigilance — we certainly don’t want to get complacent as if the job is done.”

Marlon Boarnet, professor and senior associate dean for academic affairs as well as director of graduate programs in urban planning and development at the USC Sol Price School of Public Policy, told me that the children’s lung study is a reminder that air quality protections and a robust economy can coexist. But he added that a strong regulatory regime, political support and decades-long commitment were “absolutely necessary” to achieving the clean air and health gains documented in the study.

“This was absolutely a result of public policy, there’s no question about it — end of story,” he said. “This would not have happened without policy. …If you want to have reduced lung capacity in our children, then by all means, leave it to the market.”

To read a full copy of the children’s lung study, visit the New England Journal of Medicine.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.

Categories: Health

California Could Install Ample Solar Power Without Damaging Habitats

Yale Environment 360 - March 17, 2015
California could generate enough electricity from solar power to exceed the state's energy demand five times over, even if solar equipment were only to be installed on and near existing infrastructure, a report in Nature Climate Change says. The report shows it is possible to substantially boost California's solar energy production without converting natural habitat, harming the environment, or moving solar installations to remote areas far from consumers. Roughly eight percent California's land area has been developed by humans, the study says, and residential and commercial rooftops provide ample opportunity for generating electricity through small- and utility-scale solar power installations. Additional solar facilities could be constructed in undeveloped areas that are not ecologically sensitive, such as degraded lands, the report notes. "Integrating solar facilities into the urban and suburban environment causes the least amount of land-cover change and the lowest environmental impact," says lead researcher Rebecca R. Hernandez.
Categories: Environment, Health

El Niño and La Niña Can Predict Severity of Tornado Season, Study Says

Yale Environment 360 - March 16, 2015
El Niño and La Niña conditions can help predict the frequency of tornadoes and hail storms in some of the most

Tornado near El Reno, Okla., in May 2013. susceptible regions of the U.S., new research published in the journal Nature Geoscience shows. Scientists have been using El Niño and La Niña conditions, which can be identified months before the climate cycles actually develop, to make more accurate forecasts of droughts, flooding, and hurricane activity. Now, a team of researchers says they can also forecast how active the spring tornado season will be based on the state of El Niño or La Niña in December, and sometimes even earlier. Moderately strong La Niña events lead to more tornadoes and hail storms over portions of Oklahoma, Texas, Kansas, and other parts of the southern U.S., the study shows, whereas El Niño patterns suppress the storms. Scientists have detected El Niño conditions over the past few weeks, which indicates that this spring will be a relatively quiet one for severe storms in the southern U.S., the authors say.
Categories: Environment, Health

London’s congestion charge and Seattle’s affordable transit

Pump Handle - March 16, 2015

In 2003, the city of London took a dramatic step in the battle against traffic congestion: It implemented a congestion charge of £5 for those driving private vehicles into an eight-square-mile central congestion zone on weekdays between 7am and 6:30pm. The fees were increased twice, and since 2011 have stood at £10. Drivers purchase day passes online, and a camera network and a license-plate-recognition system allow for enforcement and penalty collection. Motorcycles, bicycles, taxis, and buses are exempt from the charges.

An essential aspect of London’s system is that it invests the revenue fees in public transportation — helping to make transit more attractive as driving downtown has become more expensive. And even without spending on more buses or drivers, the fee system helped. After the congestion charge began, bus congestion delays dropped 50%, while ridership increased 14%.

While the program has certainly succeeded in reducing traffic congestion, safety advocates have raised concerns about the possibility of faster traffic speeds resulting in more crashes. Now, the Washington Post’s Emily Badger reports on new research with an encouraging finding: Central London’s roads have actually become safer since the congestion charge began.

Colin Green, John Heywood, and Maria Navarro of the Lancaster University Management School analyzed crash data, and find a “substantial and significant” decline in serious and fatal crashes both within the congestion zone and in the surrounding areas following the system’s implementation. Badger summarizes the findings:

In total, the researchers conclude that congestion pricing in Central London has been associated with 30 fewer crashes a month in the area, a drop of about 40 percent. Meanwhile, they estimate that the policy has led to about 46 fewer serious and fatal collisions a year — and 4.6 fewer deaths.

This wasn’t an obvious result when the city began this experiment a decade ago. Buses, taxis, motorcycles and bikes are exempt from the charge, which now costs £10 a day (it’s enforced through a series of video cameras and license plate readers). It’s possible that any safety gains from having fewer cars on the road might have been wiped out by other changes created by the policy — if, for instance, faster travel turned fender-benders into major crashes, or if more taxis and bikes flooded the roads, or if cars simply changed when and where they drive to skirt the congestion fee.

A system that reduces both pollution and congestion benefits public health. If a city is going to expect a large portion of its workers and residents to switch from driving to riding the bus, though, it had better have a high-quality, affordable bus system. Congestion reductions can make for a faster bus trip, but that’s little help if the bus doesn’t stop near your home or workplace, or if it’s not sufficiently usable for parents with small children or people with disabilities. Congestion fees can fund expansions in transit service, but voters are likely to be skeptical of new service that won’t materialize until a congestion-charge system is implemented.

As far as making transit more financially attractive than driving, Seattle recently began discounting fares for lower-income residents — specifically, those whose household incomes are at or below 200% of the federal poverty level ($47,700 for a family of four in 2014). Rides are now $1.50 — a discount of more than 50% off peak fares — when riders use an ORCA smart card. King County transit officials anticipate getting ORCA cards to 100,000 qualified people, in part by relying on an outreach network developed to enroll people in health plans that recently became available under the Affordable Care Act. One driving force behind Seattle’s program is concern for the region’s economy, explains the New York Times’ Kirk Johnson:

The problem it addresses is that many commuters from places like SeaTac, an outlying suburb, are too poor to live in Seattle, where prices and rents are soaring in a technology-driven boom. If they are pushed out so far that they cannot afford to get to work or give up on doing so, backers of the project said, Seattle’s economy could choke.

“I would characterize this as a safety valve,” said Dow Constantine, the King County executive and chairman of Sound Transit, a transportation agency serving multiple counties in the region. From 1999 to 2012, Mr. Constantine said, 95 percent of the new households in King County have been either rich or poor, earning more than $125,000 a year or less than $33,000, with hardly anything in between.

It’s in everyone’s interest for people to be able to get where they need to go without spending hours sitting in traffic. Studying outcomes in cities like London and Seattle that try bold new approaches to transportation gives us important data to inform future transportation policies.

Categories: Health

Designing Wetlands to Remove Drugs and Chemical Pollutants

Yale Environment 360 - March 16, 2015
Drinking water supplies around the world often contain trace amounts of pharmaceuticals and synthetic compounds that may be harmful to human health. One solution being tried in the U.S. and Europe is to construct man-made wetlands that naturally degrade these contaminants. BY CARINA STORRS
Categories: Environment, Health

Designing Wetlands to RemoveMedical Wastes and Pollutants

Yale Environment 360 - March 16, 2015
Drinking water supplies around the world often contain trace amounts of pharmaceuticals and synthetic compounds that may be harmful to human health. One solution being tried in the U.S. and Europe is to construct man-made wetlands that naturally degrade these contaminants. BY CARINA STORRS
Categories: Environment, Health

Obama Administration Doubles Size of Two Key California Marine Sanctuaries

Yale Environment 360 - March 13, 2015
The Obama administration yesterday expanded protections for two major marine sanctuaries off the coast of San Francisco,

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Sea stars on the shores of Gulf of the Farallones National Marine Sanctuary California — the Gulf of the Farallones and Cordell Bank national marine sanctuaries — doubling their extent to create a protected area the size of Connecticut. The sanctuaries encompass a wide array of habitats, including estuarine wetlands, rocky intertidal habitat, open ocean, and shallow marine banks, as well as areas of major upwelling where nutrients come to the surface and support a vast array of marine life, the National Oceanic and Atmospheric Administration said. The expansion comes after more than a decade of of community action, scientific research, and political effort. Although it was nearly unanimously supported by San Francisco Bay Area residents, the expansion faced strong opposition from the oil and gas industry, which will now be barred from drilling in the region.
Categories: Environment, Health

Glimmer of hope for beleaguered Chemical Safety Board

Pump Handle - March 12, 2015

Cronyism, retaliation, and abuse of power are just a few of the many unsavory terms and themes on full display at last week’s congressional hearing about the US Chemical Safety Board (CSB). It was the second time in less than 10 months that CSB chairman Rafael Moure-Eraso, PhD and board members have been called before the House Committee on Oversight and Government Reform (Committee).

For me, and others in the worker health and safety community, it was disappointing and discouraging to watch the four-hour spectacle. Congress pays too little attention to the causes and toll of work-related injuries and illnesses. It’s a rare occasion when the head of a workplace safety agency is given the congressional stage. When it does, I want them talking about protecting workers’ lives and health, not about their pissing match with the Inspector General. [Was I the only person talking to my computer saying “sign the damn form”?]  At the Committee’s June 2014 hearing, we heard allegations of retaliation against those with dissenting views, and the use of personal email for official business. Last week’s hearing added more including new questionable steps at the CSB to elevate the chair’s power.

Others have written about the beleaguered agency‘s problems (here, here, here), and members of the Committee, both Republican and Democrat, were unanimous in their calls for the chairman to resign, retire, be fired, or step down. For all the dark clouds hanging over the CSB, a glimmer of hope pierced the tension filled hearing room. Rick Engler, who was sworn in on February 5 as the CSB’s fourth board member, pledged to get the agency back on track. Among others, he said the reforms he’ll be seeking should include:

  • “Hold frequent, publicized, public business meetings and votes and take other steps to ensure public transparency. Every public meeting agenda should include ample time for public statements and dialogue. I reject any notion that carrying out the people’s business by a public agency is merely theater.”
  • “Ensure that CSB Members and staff work together collegially, where all views are respected, even when there are disagreements. It is especially important to respect differing scientific viewpoints.”
  • Resolve the controversy over CSB governance including the Board’s role—not just the chair’s—-in deciding budgets and major use of funds, deciding key contracts, and approving appointment of department heads.

As the hearing was wrapping up and ranking member Elijah Cummings (D-MD) was preparing to offer his closing remarks, he gave Rick Engler the last word. Engler described what happened at the CSB in the lead-up to the congressional hearing:

“…which involved going over voluminous documents and involving an outside consultant to, frankly, spin what cannot be spun. I want to go on the record to point out that I said—-and I think this is pretty close to a precise quote—‘I refuse to participate in this process.'”

Engler went on:

“This agency has no credibility whatsoever to tell anyone outside the agency virtually anything around its internal practices. …I am dedicated to the mission of the agency. I want to move forward. I hope to be back here before your committee and to work with the Inspector General, but based on whether we are accomplishing the mission of the agency, not whether we are taking steps that have been described today to interfere with the mission of the agency. I pledge to you that’s why I am here, that’s what I’m going to work for, and I look forward to coming back to this committee and to be accountable to all the relevant stakeholders and the Inspector General in the months ahead.”

Congressman Cummings responded, “to hear that is refreshing.”

Categories: Health

Bubbling From Melting Glaciers Makes Fjords Noisiest Places in Oceans

Yale Environment 360 - March 12, 2015
Bubbles gushing from melting glaciers and their icebergs make fjords the noisiest places in the oceans, according to

Listen to sound of bubbles escaping melting ice. research published in Geophysical Research Letters. Researchers used underwater microphones to record noise levels in three bays where glaciers flow into ocean fjords and icebergs calve from glaciers. They found that average noise levels from bubbles in these fjords exceeded those generated by all other sources, including weather, wildlife, and machines such as ships and sonar devices. Glacial calving contributed some of the noise, but the constant melting and bubbling was the real culprit, the researchers said. Their findings raise questions about how the underwater noise in the fjords — which are foraging hotspots for seabirds and marine mammals and important breeding habitat for harbor seals — will affect animals as climate change further increases melting rates.
Categories: Environment, Health

On the River Nile, a Move to Avert a Conflict Over Water

Yale Environment 360 - March 12, 2015
Ethiopia’s plans to build Africa’s largest hydroelectric dam on the Nile have sparked tensions with Egypt, which depends on the river to irrigate its arid land. But after years of tensions, an international agreement to share the Nile’s waters may be in sight. BY FRED PEARCE
Categories: Environment, Health

Warming To Sharply Increase For Remainder of 21st Century, Paper Says

Yale Environment 360 - March 11, 2015
Within a decade, the earth — and particularly the northern hemisphere — will begin warming at rates unprecedented in the last 1,000 to 2,000 years, according to new research in the journal Nature Climate Change. Examining the rate of temperature increases in 40-year intervals over the past 2,000 years, the scientists concluded that temperatures had fluctuated up or down by about 0.2 degrees F over each interval. In the past 40 years, however, warming has approached 0.4 degrees F per decade. And beginning in 2020, temperatures could start to rise by 0.7 degrees F per decade and continue at that rate until at least 2100. Warming will be especially pronounced in the Arctic, where temperatures are expected to soar by 1.1 degrees F by 2040. The scientists warned that such greenhouse gas-driven warming is moving the planet into an unstable climatic state.
Categories: Environment, Health

Not an “accident”: Alejandro Anguiana, 41, suffers fatal work-related injury in Kingsbury, IN

Pump Handle - March 11, 2015

Alejandro Anguiana, 41, suffered fatal traumatic injuries on Friday, March 6, 2015 while working at Markman Peat Corp. in Kingsbury, Indiana. ABC57 reports:

  • Mr. Anguiana was a payload/forklift operator. A co-worker found Mr. Anguiana trapped in a running piece of machinery. EMS was called to the scene at 6:20 am.

WISHTV says the machinery was a “peat-loading conveyor belt.”

WSBT.com reports:

  • “Sheriff John Boyd said the man was pulled in when his sweatshirt got wrapped around the power takeoff shaft that turns to operate the machine. “
  • “Several employees were involved in turning off the machine and cutting off clothing to free Anguiano, who was unconscious.”
  • “Markman Peat, also known as New Plant Life, has existed in Kingsbury for some 30 years. … The company packages a variety of soils and rocks used for landscaping and its products in individual-sized bags are found at major retailers like Menard’s.”

In 2002, at a Markman Peat Corp. facility in Morrison, Illinois, a 19-year old employee was fatally injured on-the-job while operating a dump truck. The facility had an unmarked railroad crossing and while driving the dump truck the employee was struck by a train. The company paid a $2,500 penalty for a serious and a willful violation.

In 2011, the Markman family sold Markman Peat Corporation to Jeff Widdop and Brian Sherrick who are in the financial services industry.

Each year, more than 100 workers in Indiana are fatally injured on-the-job. The Bureau of Labor Statistics reports 123 work-related fatal injuries in Indiana during 2013 (preliminary data, most recent available.) Nationwide, at least 4,405 workers suffered fatal traumatic injuries in 2013.

The AFL-CIO’s annual Death on the Job report notes:

  • Indiana OSHA has 39 inspectors to cover more than 144,000 workplaces.
  • The average penalty for a serious workplace safety violation in Indiana is $1,054.

Indiana OSHA has until early-September 2015 to issue any citations and penalties related to the incident that stole Alejandro Anguiana’s life. It’s likely they’ll determine that Anguiana’s death was preventable. It was no “accident.”

Categories: Health

Occupational Health News Roundup

Pump Handle - March 10, 2015

The same day that NPR and ProPublica published their investigation into the dismantling of the workers’ compensation system, OSHA released its own report, “Adding Inequality to Injury: The Cost of Failing to Protect Workers on the Job.” The agency writes that the failure of employers to prevent millions of work-related injuries and illnesses each year coupled with changes to workers’ compensation systems is exacerbating income inequality and pushing many workers into poverty. The report states:

For many injured workers and their families, a workplace injury creates a trap which leaves them less able to save for the future or to make the investments in skills and education that provide the opportunity for advancement. These injuries and illnesses contribute to the pressing issue of income inequality: they force working families out of the middle class and into poverty, and keep the families of lower-wage workers from entering the middle class. Work injuries hamper the ability of many working families to realize the American Dream.

The OSHA report, which includes the personal stories of injured workers, noted that even with workers’ compensation benefits, the incomes of injured workers are typically $31,000 less over 10 years than if the worker hadn’t been injured in the first place. And while workers’ compensation was designed to protect workers, OSHA reports that it’s workers and taxpayers who are shouldering the burden.

In reality, the costs of workplace injury and illness are borne primarily by injured workers, their families, and taxpayer-supported safety-net programs. State legislatures and courts have made it increasingly difficult for injured workers to receive the payments for lost wages and medical expenses that they deserve. As a result of this cost-shifting, workers’ compensation payments cover only a small fraction (about 21 percent) of lost wages and medical costs of work injuries and illnesses; workers, their families and their private health insurance pay for nearly 63 percent of these costs, with taxpayers shouldering the remaining 16 percent.

The Center for Public Integrity conducted a Q&A about the report with David Michaels, U.S. assistant secretary of labor for occupational safety and health. In responding to a question about what’s driving changes to workers’ comp, Michaels replied: “This race to the bottom is being driven by employers in every state who see an opportunity to have lower costs.”

To access a full copy of the new report, visit OSHA.

In other news:

Huffington Post: McDonald’s and its industry peers in the International Franchise Association are suing Seattle to stop the city’s scheduled minimum wage increase to $15 an hour. Writer Ron Fein reports that the fast food giant isn’t just claiming that a wage increase is bad for business, but that it actually violates the U.S. Constitution, specifically the 14th amendment. Fein writes: “That amendment was passed in 1866 to ensure equal rights for the freed slaves, and it says that no state may ‘deny to any person … the equal protection of the laws.’ According to the Hamburglar, treating a franchised business differently from a local business violates this Equal Protection Clause.”

The Californian: Roberto Robledo reports that California state lawmakers are considering a bill that would establish a pilot fund to provide agricultural workers with medical care for workplace-related injuries and illnesses as well as for health problems not related to work. Financing for the measure would come through funds that agricultural employers already pay toward workers’ compensation. Robledo reports that the idea of providing farmworkers with “24-hour medical service appeals to some growers.” The story quotes the bill’s sponsor, Luis Alejo Jr.: “Agriculture workers are exposed…to the elements, extreme heat and cold and they work in an industry that strains the body. Yet they don’t have access to even the most basic of healthcare services.”

Modern Healthcare: Steven Ross Johnson writes about the health care industry’s opposition to a proposed OSHA rule that would require health care employers and other industries to report cases of work-related injuries and illnesses. The occupational health data would then be available to the public online. However, some health care industry advocates say the reporting requirement could compromise patient privacy. Johnson, who noted that worker injury rates at hospitals were nearly twice the national average of private industries in 2011, talked to worker advocates who say the new rule could elevate the conversation around nurse safety: “Unfortunately, I don’t think the musculoskeletal-injury situation has captured the attention of the public, the scientists and the policymakers,” said Pamela Cipriano, president of the American Nurses Association.

Washington Post: Reporter Josh Hicks writes that the Justice Department will begin notifying thousands of federal employees that they can now sue the government for late payments during the government shutdown of 2013. Specifically, eligible workers can now join an ongoing lawsuit claiming that the government owes damages in accordance with the Fair Labor Standards Act. The article states: “Many workers took months to recover financially from the impact of the government shutdown,” said Heidi Burakiewicz, an attorney with the D.C. law firm representing the plaintiffs. “They should not be financially punished for circumstances beyond their control.”

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.

Categories: Health

Solar and Wind on Track to Dominate New U.S. Power Capacity in 2015

Yale Environment 360 - March 10, 2015
U.S. electric companies expect to install more than 20 gigawatts (GW) of utility-scale generating capacity this year and

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Power generating capacity set to come online in 2015. 60 percent of that will be wind and solar power, according to a U.S. Energy Information Administration analysis. Energy companies plan to retire 16 GW of generating capacity this year, EIA numbers show, and 81 percent of that will be coal-fired power plants. The large number of coal plant retirements can be attributed to the EPA's Mercury and Air Toxics Standards, which are slated to go into effect this year. Many companies decided that shuttering coal generators would be more cost effective than retrofitting them to meet the new standards, the EIA said. Natural gas power plants — which, although they burn fossil fuels, emit significantly less carbon than coal-fired plants — will make up roughly 32 percent of the additional capacity.
Categories: Environment, Health

Blue Crabs Are Moving Into Gulf of Maine's Warming Waters, Study Says

Yale Environment 360 - March 09, 2015
Blue crabs have become the first documented commercially important species to move into the Gulf of Maine

Blue crab caught 80 miles north of its historic range. a migration that may be driven by climate change, according to ecologist David Johnson of the Marine Biological Laboratory. Although the historic northern limit of the blue crab is Cape Cod, Massachusetts, scientists and resource managers have observed blue crabs as far north as northern Maine and Nova Scotia, Canada. Johnson says that warmer ocean temperatures in 2012 and 2013, which were 1.3 degrees C higher than the previous decade's average, allowed the crabs to move north. In the 1950s, blue crabs were observed in the gulf during a time of warmer waters, Johnson notes in the Journal of Crustacean Biology, but once the gulf returned to average temperatures, the crabs disappeared. He added that "recent observations of blue crabs may be a crystal ball into the future ecology of the Gulf of Maine."
Categories: Environment, Health
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