Environmental

Farmland runoff containing fertilizers and livestock waste, some of it from as far away as the Corn Belt, is the main source of the nitrogen and phosphorus that cause the annual Gulf of Mexico "dead zone." Image credit: Donald ScaviaANN ARBOR—Spring floods across the Midwest are expected to contribute to a very large and potentially record-setting 2013 Gulf of Mexico "dead zone," according to a University of Michigan ecologist and colleagues who released their annual forecast today, along with one for the Chesapeake Bay.
The Gulf forecast, one of two announced by the National Oceanic and Atmospheric Administration, calls for an oxygen-depleted, or hypoxic, region of between 7,286 and 8,561 square miles, which would place it among the 10 largest on record.
The low end of the forecast range is well above the long-term average and would be roughly equivalent to the size of Connecticut, Rhode Island and the District of Columbia combined. The upper end would exceed the largest ever reported (8,481 square miles in 2002) and would be comparable in size to New Jersey.
Farmland runoff containing fertilizers and livestock waste, some of it from as far away as the Corn Belt, is the main source of the nitrogen and phosphorus that cause the annual Gulf of Mexico hypoxic zone. In its 2001 and 2008 action plans, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force, a coalition of federal, state and tribal agencies, set the goal of reducing the five-year running average areal extent of the Gulf hypoxic zone to 5,000 square kilometers (1,950 square miles) by 2015.
Little progress has been made toward that goal. Since 1995, the Gulf dead zone has averaged 5,960 square miles, an area roughly the size of Connecticut.
"The size of the Gulf dead zone goes up and down depending on that particular year's weather patterns. But the bottom line is that we will never reach the action plan's goal of 1,950 square miles until more serious actions are taken to reduce the loss of Midwest fertilizers to the Mississippi River system, regardless of the weather," said U-M aquatic ecologist Donald Scavia, director of the Graham Sustainability Institute, who contributes to both the Gulf and Chesapeake Bay forecasts.
This year's Chesapeake Bay forecast calls for a smaller-than-average dead zone in the nation's biggest estuary. The forecast from Scavia and University of Maryland researchers has three parts: a prediction for the mid-summer volume of the low-oxygen hypoxic zone, one for the mid-summer oxygen-free anoxic zone, and a third that is an average value for the entire summer season.
An oxygen-starved hypoxic zone, commonly called a dead zone and shown in red, forms each summer in the Gulf of Mexico. Fish and shellfish either leave the oxygen-depleted waters or die, resulting in losses to commercial and sports fisheries. Credit: NOAAThe forecast calls for a mid-summer hypoxic zone of 1.46 cubic miles, a mid-summer anoxic zone of 0.26 to 0.38 cubic miles, and a summer average hypoxia of 1.108 cubic miles, all at the low end of previously recorded dead zones. Last year, the mid-summer hypoxic zone was 1.45 cubic miles. Because of the shallow nature of large parts of the estuary, the forecast focuses on water volume expressed in cubic miles instead of surface area in square miles.
The annual Gulf forecast is prepared by researchers at U-M, Louisiana State University and the Louisiana Universities Marine Consortium. The Bay forecast is provided by U-M and the University of Maryland's Center for Environmental Science. Both studies are funded by NOAA.
The forecasts are based on nutrient runoff and river-and-stream data from the U.S. Geological Survey, which are then fed into computer models developed with funding from NOAA's National Centers for Coastal Ocean Science.
"Monitoring the health and vitality of our nation's oceans, waterways and watersheds is critical as we work to preserve and protect coastal ecosystems," said Kathryn Sullivan, acting undersecretary of commerce for oceans and atmosphere and acting NOAA administrator. "These ecological forecasts are good examples of the critical environmental intelligence products and tools that help shape a healthier coast, one that is so inextricably linked to the vitality of our communities and our livelihoods."
Floods inundated much of the Midwest this spring. Several states, including Minnesota, Wisconsin, Illinois and Iowa, had spring seasons that ranked among the 10 wettest on record. Iowa had its wettest spring on record, with 17.61 inches of precipitation, according to the National Climatic Data Center.
Nutrient-rich runoff from those farming states ends up in the Mississippi River and eventually makes its way to the Gulf. The amount of nitrogen entering the Gulf of Mexico each spring has increased by about 300 percent since the 1960s, mainly due to increased agricultural runoff.
According to U.S. Geological Survey estimates, 153,000 metric tons of nutrients flowed down the Mississippi and Atchafalaya rivers to the northern Gulf in May 2013, an increase of 94,900 metric tons over last year's drought-reduced 58,100 metric tons. The 2013 input is 16 percent higher than the average nutrient load estimated over the past 34 years.
In the Gulf and the Bay, the nutrient-rich waters fuel explosive algae blooms. When the algae die and sink, bottom-dwelling bacteria decompose the organic matter, consuming oxygen in the process. The result is a low-oxygen (hypoxic) or oxygen-free (anoxic) region in the bottom and near-bottom waters: the dead zone.
Fish and shellfish either leave the oxygen-depleted waters or die, resulting in losses to commercial and sports fisheries. In the Gulf, the dockside value of commercial fisheries was $629 million in 2009, and nearly 3 million recreational anglers contributed more than $1 billion to the region's economy.
Chesapeake Bay dead zones, which have been highly variable in recent years, threaten a multi-
year effort to restore the bay's water quality and to enhance its production of crabs, oysters and other fisheries. The Geological Survey estimates that 36,600 metric tons of nitrogen entered the estuary from the Susquehanna and Potomac rivers from January through May, which is 30 percent below the average loads estimated between 1990 and 2013.
The final Chesapeake Bay measurement will be released in October following surveys by the Maryland Department of Natural Resources and the Virginia Department of Environmental Quality.
The 2013 Gulf estimate is based on the assumption of no significant tropical storms in the two weeks preceding or during the official measurement survey cruise scheduled from July 25 to Aug. 3. If a storm does occur, the size estimate could drop to a low of 5,344 square miles, slightly smaller than Connecticut.
Last year's Gulf dead zone was the fourth-smallest on record, due to drought conditions, and covered about 2,889 square miles, an area slightly larger than Delaware.
Related Links:

U-M Sustainability fosters a more sustainable world through collaborations across campus and beyond aimed at educating students, generating new knowledge, and minimizing our environmental footprint. Learn more at sustainability.umich.edu.

A rise in fish farms has meant cheap, fast-growing protein to feed the world's growing human population. But a new study suggests that countries located at lower latitudes – many of which rely heavily on fish farming – may be most at risk for fish disease outbreaks. The tropical environments in countries near the equator are ripe for breeding waterborne pathogens. 

Aquaculture, the technical term for the farming of aquatic plants and animals, is the fastest-growing agricultural industry in the world. The term refers to farming in all sorts of water environments, including ponds, rivers, lakes and controlled areas in the ocean. According to the Food and Agriculture Organization of the United Nations, more than 90 percent of these fish farms are located in developing countries, which often have warm, tropical environments, conducive to raising fish year-round.
A study published earlier this year in the Journal of Applied Ecology, however, shows that operations near the equator are also more prone to dangerous and rapid disease outbreaks that could wipe out entire stocks of fish.
Tommy Leung, a lecturer in parasitology and evolutionary biology at the University of New England in Armidale, Australia, and his colleague Amanda Bates at the University of Tasmania, reviewed 114 previously published reports on disease outbreaks at fish farms from Norway to South America.
The implications of these findings for developing countries, many of which are located near the equator, could be dire.
"A lot of these countries are really dependent on aquaculture as a way to have a secure food source, so it provides them with food security, as well as a way of supporting their economy," said Leung.
In their analysis, Leung's team considered the geographical location of the fish farm outbreaks, the severity of the outbreaks, the type of fish or shellfish involved, and the type of farm -- fresh or saltwater, and how the farms were separated from the surrounding waters. They also considered the types of pathogens that caused disease, generally viruses, bacteria or parasites.
Diseases ranged from skin flukes, which make fish scales appear discolored and peel off, to salmon anemia, a viral disease thought to be carried by sea lice.
The findings showed that the closer the fish farms were to the equator, the more likely they were to have an outbreak and the more severe the outbreaks were compared to fish farms located farther away from the equator. Young fish and shellfish were particularly susceptible to the deadly outbreaks. Leung said, on average, disease outbreaks in tropical areas wipe out 88 percent of the fish in any given stock. This is mainly because diseases tend to breed and spread faster in the warmer waters of the tropics.
In addition, disease is difficult to contain in water. "Unlike on a dairy farm where if you have a sick calf you can put them aside to quarantine them, it's much harder to quarantine in an aquatic environment," said Leung.
According to Jeffrey Lotz, an aquaculture specialist at the University of Southern Mississippi in Ocean Springs, Miss., diseases will always threaten aquaculture. "Certainly there have been more problems in the tropics but there are disease problems in the [higher] latitudes as well," he explained.
Lotz said he's worried about the implications for imports. According to the National Oceanic and Atmospheric Administration the U.S. imports 85 percent of its seafood, more than half of which is from aquaculture operations rather than wild-caught.
While imported pork, beef and chicken are subject to inspections by the Food and Drug Administration, fish imports don't face the same scrutiny. According to Lotz, the less stringent inspection regulations could allow diseased fish imported from tropical countries onto grocery store shelves in the U.S., potentially posing a threat to public health.
Both Leung and Lotz are concerned about the implications for the future, saying global warming could result in rising temperatures and thus, a rise in the incidence of fish disease across the globe. Lotz said some of the tropical diseases will likely move farther from the equator and the overall prevalence of fish disease will increase, impacting both supply and food safety.
Contacts and sources:
Inside Science News Service
By Tegan Wendland, ISNS Contributor

KUWAIT, June 15 (KUNA) -- Environment Public Authority (EPA) has carried out a surveillance of beaches opposing Chest Hospital and Maternity Hospital following discovery of dead fish near these beaches.
A team from EPA's water pollution monitoring department noticed, yesterday and today, scattered quantities of dead fish but then concluded that they were dead for long time and not recently, EPA said in a statement Saturday.
EPA said it contacted the municipality to clean the beaches, asserting keenness to follow up any reports of similar incidents to preserve the environment. (end) zak.bs KUNA 152107 Jun 13NNNN

Galway Bay fm newsroom - Marine Institute testing carried out following the discovery of dead fish on Loughrea Lake last month (May) has found no significant bacteria or viral disease.
Samples were taken and sent for labortatory analysis after 100 dead perch were recovered on May 12th.
A spokesperson for Inland Fisheries Ireland says the cause of the fish kill is not clear, however it is quite likely to be just stress-related and associated with spawning.
Fish can get stressed during spawning time resulting in the weakening of their immune systems.
A statement adds that the number of fish killed was quite small in terms of the stock in the lake and other species were not impacted.
Inland Fisheries concludes that Loughrea Lake has produced good trout fishing in recent weeks so it appears to be an isolated incident.

Please bear with us while we re-organise our new site - we've made it a little slicker and a lot faster - come back soon to see the finished product.

"We know very little at this point, we have the D.E.P coming out to conduct some follow-up tests. We've already done some initial testing of the water, no obvious contaminants have been found in the water," said Borough Manager Dawn Human.
Residents are being asked not to fish or go into the lake until authorities finish testing the water.
Human says it's possible the dead fish may have washed up in this week's storms.

Park spokeswoman Christie Vanover says the mysterious fish deaths and foam were found in the Overton Arm, where the lake extends north. She says the foam appeared to be coming from the mouth of the Virgin River and stretched about eight miles down to Echo Bay.
Officials said over the weekend that the Southern Nevada Water Authority is working with the National Park Service to collect water samples.
The authority is also keeping track of water at its two water treatment facilities to ensure the quality meets the federal standards of the Safe Drinking Water Act.

Think your friends should see this? Share it with them!

Fish biologists in Southern Oregon are worried that abnormally warm water in the Rogue River could lead to a a die-off of chinook salmon. Pictured here is a die-off from Klamath River in 2002. / Mail Tribune file

The Project / Operations Director for the Corps of Engineers R. J. Harms confirmed there have been reports of dead carp washing up on the bank at the north end of the lake in the military marina area, and as far south as around the city of Milford and the Farnum Creek arm of the lake.
Harms said Kansas Wildlife, Parks, and Tourism has done some preliminary investigation. "And it looks like what they're thinking is that these fish were probably oxygen stressed, and have come down the river." Harms noted they were probably in the shallow water pools in the Republican River, and were stressed with low oxygen levels. "And then with the recent rains, the inflows we've had into the lake, some of those fish have been basically brought down into the lake then, and have died here at the lake."

FAIRBANKS — After surveying Quartz Lake on Wednesday, officials at the Alaska Department of Fish and Game in Fairbanks are hoping the fish die-off that occurred this winter isn't as large as first thought.

Sport fish research supervisor Tom Taube in Fairbanks said two technicians and a biologist boated around the entire shoreline of the 1,500-acre lake and counted 121 dead arctic char and rainbow trout, most of which were large fish in the 20-plus inch range.

"It wasn't thousands," Taube said.
That was the report ADFG got earlier this week after the ice went out on Quartz Lake last weekend. The department received several calls from fishermen and local residents that hundreds, if not thousands, of dead fish were littering the shoreline around the lake.
"We're kind of hoping there are some large fish left and they're just in deeper water," Taube said. "It looks like there was some level of mortality there but not a total mortality."
Biologists attributed the winterkill to the long winter that kept thicker ice on the lake longer than normal, reducing the amount of oxygen for fish.
ADFG doesn't plan to put nets out to catch fish to see what's left in the lake because the department stocked the lake with several thousand catchable-size rainbow trout on Tuesday, Taube said. There's also the fact that ADFG doesn't know how many fish were in the lake last fall.
"It would be a pretty involved project to determine what was lost and what's left," he said.
The department also got a report of a winterkill at Polaris Lake on Eielson Air Force Base, a lake that has had similar die-offs in past years, Taube said.
"As we get reports (of winterkills) we're trying to check them out," he said. "If any year it was going to happen this was the year it could."
Contact staff writer Tim Mowry at 459-7587.

GEARY COUNTY, Kan. (WIBW) -- The Army Corps of Engineers at Milford Lake confirms that they've received several reports of dead carp turning up in different areas like boat ramps and beach areas, mostly in the northern part of the lake.

The Corps of Engineers has worked with biologists from the Kansas Department of Wildlife and Parks and they believe that the fish were caught in shallow pools in the Republican River in between rainfalls, causing them to die from stress and oxygen deprivation.

When another rainfall came and the river started to flow, the fish were pushed into the lake.

One viewer reported seeing 70-75 dead fish along the shoreline and more out in the lake while boating.

Officials say there are no safety issues.