When you imagine fish in the Chesapeake Bay, top predators probably come to mind. But the most important fish in the Bay weighs no more than a pair of playing cards, measures no longer than the width of your hand and is more abundant than any other fish that calls the Chesapeake home.
The bay anchovy (Anchoa mitchilli) can be found in great numbers along the Atlantic coast and in all parts of the Chesapeake Bay. “It is the single most abundant fish on the east coast of North America," said fisheries scientist Ed Houde. “That in itself says something about its importance.”
Because it is such an oft-consumed prey item for so many predators, the bay anchovy is considered a forage fish. But the bay anchovy stands out among forage species. Scientists have long known, for instance, that the bay anchovy is a major source of energy fueling the growth and production of predators in the Chesapeake, and can even comprise up to 90 percent of the diets of predatory fish in the fall. A recent investigation into the diets of five predatory fish found that the bay anchovy was the fishes’ most common prey, confirming the bay anchovy is the most important forage species in the Bay ecosystem.
“We’ve studied the production and consumption of bay anchovy in the Chesapeake Bay, and the numbers are impressive,” said Houde, who worked at the University of Maryland Center for Environmental Science’s Chesapeake Biological Laboratory for more than 35 years and served as the institution’s Vice President for Education before retiring in July 2016. According to Houde, about 50,000 tons of bay anchovy can be found in this estuary at any given time—but an average of 458,000 tons are produced here each year. “That means a huge amount is being eaten and is fueling the production of Bay predators,” Houde said.
According to Houde, several characteristics make the bay anchovy the perfect prey fish. First, it’s a small fish, which means a range of predators both big and small can fit the fish into their mouths. Second, it’s a fecund fish, which means it spawns large numbers of eggs; eggs, larvae, juveniles and adults are eaten by predators. Third, there are a lot of them, almost everywhere, all the time. While other prey species may only inhabit certain areas of the Bay at certain times of year, the bay anchovy is generally available throughout the Bay most of the year.
Indeed, the bay anchovy is surprisingly tolerant of both the normal fluctuations observed in an estuarine environment and the hostile conditions that can occur when this environment is stressed. Through laboratory experiments and field work, Houde and his students have found that low dissolved oxygen, for instance, may not impact the bay anchovy like it impacts many other species. Areas of low dissolved oxygen—which occur in the Bay each summer, and which can suffocate shellfish and other organisms living on or near the bottom—seem to affect the distribution of bay anchovy but not their death rates, driving adults into the lower portion of the Bay. Coincidentally, it is in this portion of the Chesapeake that bay anchovy larvae and young are most likely to thrive. It may seem counterintuitive, but in this way, low dissolved oxygen can enhance the bay anchovy’s reproductive success.
“This is not an argument to support benefits of low dissolved oxygen in the Bay,” Houde cautioned. “But in the case of the anchovy, it does seem to promote conditions that increase its productivity.”
The Maryland Department of Natural Resources and Virginia Institute of Marine Science have gathered survey data on bay anchovy abundance for decades, and the University of Maryland Center for Environmental Science has also tracked this number as an indicator of Bay health. While bay anchovy populations fluctuate seasonally and annually and the fish is less abundant now than in the decades before 1990, Houde does not believe the bay anchovy has declined since the mid-1990s.
That said, Houde acknowledges that there must be environmental thresholds the bay anchovy cannot successfully cross. Little research has been done into the effects that chemical contaminants could have on the fish, and environmental conditions that lower plankton productivity—the mainstay of the bay anchovy’s diet—could have substantial effects on anchovy production and abundance.
How can we ensure the continued abundance of the most important fish in the Bay? “Ensuring the bay anchovy population remains healthy depends on keeping estuaries healthy,” Houde said. “Good water quality that supports abundant zooplankton to fuel anchovy production is what we need to maintain the health of anchovies. That’s not so different from [protecting] most of the things in the Bay.”
Through the Chesapeake Bay Watershed Agreement, the Chesapeake Bay Program has committed to improving our understanding of the role of forage species in the Bay. Learn about our work to develop a strategy for assessing the Bay’s forage base.
Air quality improvements throughout the Potomac River watershed—due primarily to the Clean Air Act—have helped improve water quality in the Chesapeake Bay, according to research from the University of Maryland Center for Environmental Science (UMCES).
When cars, power plants and other sources emit air pollution, it can be carried by wind and weather over long distances until it falls onto land or directly into the water. In fact, scientists estimate that one third of the nitrogen in the Chesapeake Bay comes from the air—through a process known as atmospheric deposition. And while studying water quality trends in the Upper Potomac River Basin, UMCES scientists confirmed that reductions in atmospheric nitrogen deposition are playing a large role in improvements in the area’s water quality.
“Most best management practices—like a riparian buffer or retention pond—only impact a relatively small area,” said Keith Eshleman, professor at UMCES’ Appalachian Laboratory and co-author of the study. “You can think about the Clean Air Act as a best management practice that affects every square meter of the watershed.”
Experts at the Chesapeake Bay Program will be able to incorporate the findings into their modeling efforts, in order to better simulate the benefits of the Clean Air Act on reducing nitrogen pollution. The study—along with other research, monitoring and data collected over the past decade—will support Bay Program decision-making during the upcoming Midpoint Assessment of the Chesapeake Bay Total Maximum Daily Load, or TMDL.
Last year, the Chesapeake Bay Program released an interactive story map illustrating how Clean Air Act regulations, as well as decades of enforcement actions, led to a steady decline in air pollution across the Chesapeake Bay watershed.
The study—“Declining nitrate-N yields in the Upper Potomac River Basin: What is really driving progress under the Chesapeake Bay restoration?”—can be found online.
Scientists expect low river flow and reduced nutrient-rich runoff from the Susquehanna and Potomac Rivers this spring to result in an average to slightly smaller-than-average dead zone in the main stem of the Chesapeake Bay this summer.
Aquatic life—from blue crabs to underwater grasses—relies on dissolved oxygen to survive. When nutrient-fueled algae blooms die and decompose, the resulting areas of little to no oxygen, known as dead zones, can suffocate underwater plants and animals. The latest forecast predicts a mid-summer hypoxic, or low-oxygen, zone of 1.58 cubic miles: close to the long-term average. The anoxic, or no-oxygen, zone is expected to reach 0.28 cubic miles in early summer and grow to 0.31 cubic miles by late-summer.
This forecast, funded by the National Ocean and Atmospheric Administration (NOAA), is based on models developed at the University of Maryland Center for Environmental Science and the University of Michigan and relies on estimated nutrient loads from the U.S. Geological Survey (USGS). According to USGS, 66.2 million pounds of nitrogen entered the Chesapeake Bay in from January to May 2016, which is 17 percent lower than average nitrogen loadings.
Over the next few months, researchers with the Maryland Department of Natural Resources (DNR) and the Virginia Department of Environmental Quality (DEQ) will monitor oxygen levels in the Bay, resulting in a final measurement of the Bay’s dead zone later this year.
Scientists at the University of Maryland Center for Environmental Science (UMCES) measured a modest improvement in Chesapeake Bay health in 2015, once again giving the estuary a “C” in their annual Chesapeake Bay Report Card.
Although the “C” grade has remained the same since 2012, the score of 53 percent marks one of the three highest since 1986: only 1992 and 2002 scored as high or higher. But unlike 2015, both those years accompanied major droughts, and according to UMCES researchers, that makes these results particularly notable.
“We’d expect to see improvements after a drought year because nutrients aren’t being washed into the Bay, fueling algae blooms and poor water quality,” said Bill Dennison, Vice President for Science Applications at UMCES, in a release. “However, in 2015 streamflow was below normal, but nowhere near the drought conditions in 1992 and 2002. Thus, the high score for 2015 indicate that we’re making progress reducing what’s coming off the land.”
The Bay Health Index is based on several indicators of Bay health, including water clarity and dissolved oxygen, the amount of algae and nutrients in the water, the abundance of underwater grasses and the strength of certain fish stocks, including blue crab and striped bass. Most of these indicators improved over the previous year; only phosphorus pollution worsened from 2014 to 2015.
"The information being released today by the University of Maryland Center for Environmental Science is very positive and consistent with the trends the Chesapeake Bay Program has been witnessing over the past few years,” said Nick DiPasquale, Director of the Chesapeake Bay Program. “We should take the opportunity to celebrate these results, but we should also recognize that the long term success of our work to restore water quality and the health of this vitally important ecosystem will depend on stepping up and sustaining our efforts over the long-term to reduce nutrient and sediment pollution discharges to streams and rivers throughout the watershed."
When it comes to scientific data, older isn't typically better. But when you are teasing out environmental trends, like temperature change, it helps to have a long record. The Chesapeake Biological Laboratory (CBL) in Solomons, Maryland, is the oldest state-supported marine laboratory on the East Coast, and it touts the longest continuous record of water temperature in the Chesapeake Bay.
CBL's 750-foot research pier on the Patuxent River was first built in 1936, and in 1938 scientists started walking out to collect thousands of daily temperature and salinity readings. Today, anyone can observe live water conditions at the pier online. In the 70 years after 1938, the laboratory documented a 2.7 degree Fahrenheit temperature increase in the water around the pier.
"And that's given a unique, long-term record that’s shown the essential elements of climate change,” said Dr. David Secor, a fisheries ecologist at CBL who first reported the trend. “That motivated our group to begin to look at how young fish that we collect here by the pier may change."
Secor’s lab has performed seining studies since 1999. His team first used a 100-foot seining net to focus on bluefish, which morphed into a project on menhaden. “We’ve basically shoe-stringed this effort along,” Secor said, describing short-term funding sources. “And I think we have a dedicated, motivated group of students and myself that will hopefully continue this on throughout my career.”
The most common species caught by the seine are Atlantic silverside, bay anchovy, and Atlantic menhaden. Another 10 percent is bluefish, blue crab, white perch, striped bass and spot. Secor said future observations depend on how well species can adapt to temperature change as well as seasonality—the conditions in spring and winter that “set the clock” for what fish are present later in the year.
“What we may see in the future, with warming, is a disruption of that clock,” Secor said. “Maybe we’ll see higher production of some things like blue crabs, but we may see diminished production of fish that don’t do so well in warmer waters such as striped bass, perch and black sea bass.”
“We saw a kingfish last year for the first time in our series,” Secor said. “These kinds of fish that we already see visiting the lower Chesapeake Bay will be coming up this way more frequently.”
Regardless of the fish that will be seen, one fair prediction for the future is that the CBL pier will be there to support the science.
“This pier has been here in purpose for 70 years but it’s been replaced several times, and that too is the result of climate events,” Secor said. “Hurricanes and tropical storms have really taken a bite out of this pier on occasion.”
In 2010, after several recent storms, the University of Maryland Center for Environmental Science received a $1.7 million grant to rebuild the pier from the National Science Foundation as part of the American Reinvestment and Recovery Act. In 2011, Hurricane Irene dealt additional damage before construction began the next year. The pier received several new pilings, an upgraded pump house, and new instrumentation to measure greenhouse gases in the air.
“It’s been rebuilt now,” Secor said, sitting on the pier’s new deck. The full length of the pier is now covered in a corrugated material designed to allow water—and fallen car keys—to pass through uninhibited.
“It’s made out of much more flexible, much more enduring materials.”
To view more photos, visit the Chesapeake Bay Program’s Flickr page
Video, Images and Text by Will Parson
Scientists expect the Chesapeake Bay to see a slightly smaller than average dead zone this summer, due to reduced rainfall and less nutrient-rich runoff flowing into the Bay from the Susquehanna River this spring.
Dead zones are areas of little to no dissolved oxygen that form when nutrient-fueled algae blooms die and decompose. Resulting low-oxygen conditions can suffocate marine life. The latest forecast predicts an early-summer no-oxygen zone of 0.27 cubic miles, a mid-summer low-oxygen zone of 1.37 cubic miles and a late-summer no-oxygen zone of 0.28 cubic miles. This forecast, funded by the National Ocean and Atmospheric Administration (NOAA), is based on models developed at the University of Maryland Center for Environmental Science and the University of Michigan.
Nutrient pollution and weather patterns influence dead zone size. According to the U.S. Geological Survey (USGS), 58 million pounds of nitrogen entered the Bay in the spring of 2015, which is 29 percent lower than last spring’s nitrogen loadings.
Researchers with the Maryland Department of Natural Resources (DNR) and the Virginia Department of Environmental Quality (DEQ) will measure oxygen levels in the Bay over the next few months. While the final dead zone measurement will not take place until October, bimonthly updates on Bay oxygen levels are available through DNR’s Eyes on the Bay.
If you’ve ever watched a solitary ant explore your countertop, you might have marveled at its tiny size. You also might have questioned how something seemingly insignificant can be such a nuisance in your aspiringly sterile kitchen. Then you remember what your tiny pioneer heralds — the impending arrival of thousands of her sisters — and she suddenly seems like a more formidable adversary.
At a few millimeters short of a typical carpenter ant, microplastics are another case of both extreme smallness and overwhelming magnitude. Microplastics are the fragments, pellets, sheets, fibers, microbeads and polystyrene that begin as improperly discarded plastic bottles and trash that get washed into our waterways. At less than five millimeters in length, they are nearly imperceptible. But plastic doesn’t degrade like most organic material, meaning the total amount of plastic in the environment doesn’t really change as it breaks down, allowing microplastics to persist in most surface waters around the globe, including the Chesapeake Bay.
University of Maryland Professor Dr. Lance Yonkos is the primary author on a study of microplastics collected from four tributaries of the Chesapeake Bay — the Patapsco, Magothy, Rhode, and Corsica Rivers. Of the 60 samples taken by the National Oceanic and Atmospheric Association (NOAA) Marine Debris Program, all but one contained microplastics.
To Yonkos, it’s not really a surprise there are microplastics in the Bay.
“We have many of the prime sources for creating and introducing microplastics to aquatic environments,” Yonkos said. Roads are a main contributor because they promote physical degradation of plastics and provide easy transport via storm drains to Bay tributaries. Yonkos listed wastewater treatment plant effluent and substantial shipping traffic.
As plastic fragments become smaller, a greater number of animals are able to swallow them—as exemplified by the recent case of a whale killed by a shard from a DVD case. When these materials break down enough reach the level of microplastics, even filter feeders like oysters can consume them.
Smaller pieces also mean more surface area, Yonkos said, which could mean more leaching, either of chemicals from the plastic itself or of the environmental contaminants that cling to its surface.
“In this way, microplastics might serve as a vehicle for introducing bioaccumulative contaminants to the food chain,” Yonkos said. The concentration of such toxic contaminants can become magnified at higher levels of the food web.
But, the science isn’t clear yet on whether microplastics represent a serious environmental or human health concern.
“Since we don’t really know yet, it is a little disconcerting to think that most of the plastics we have created over the past 70 years are still in the environment,” Yonkos said.
And microplastics are here to stay. With no feasible method for removing microplastics that are already in the environment, measures like improved recycling and decreased use of offending products — like those that include microbeads, which would be banned by the state of Maryland according to legislation passed recently — could improve the situation going forward.
“The take home message is prevention,” Yonkos said. “If we want to reduce microplastics in the oceans we need to limit their release at the source.”
To view more photos, visit the Chesapeake Bay Program's Flickr page.
The R/V Rachel Carson is docked on Solomons Island. At 81 feet long, the red and blue research vessel stands out against the deadrise workboats that share the Patuxent River marina. Her mission today is to lead researchers from the University of Maryland Center for Environmental Science (UMCES) to the Chesapeake Bay’s dead zone.
Every summer, this so-called “dead zone” forms in the main stem of the Bay. The area of low-oxygen water is created by bacteria as they feed on algae blooms growing in nutrient-rich water. The dead zone persists through the warm summer months because the Bay is stratified into two layers: a surface layer of lighter, fresher water that mixes with the atmosphere, and a bottom layer of denser, saltier water, where oxygen depletion persists. These layers won’t mix until the cooler temperatures of autumn allow the surface waters to sink.
To find the dead zone, Director of Marine Operations and Rachel Carson Captain Michael H. Hulme takes us to one of the deep troughs that run down the center of the Bay. Geologic remnants of the ancient Susquehanna River, these troughs can reach up to 174 feet deep in an estuary whose average depth is just 21 feet. Hulme anchors offshore of Calvert Cliffs State Park.
The boat is equipped with a dynamic positioning system, which holds it in place regardless of wind or waves. This allows the captain to step away from the helm and offer his hands on deck. “Being able to hover over that [specific] latitude and longitude is what makes the Rachel Carson so unique,” said Hulme. It’s also one of the reasons the vessel is so useful to scientists, who often return to the same sampling site again and again over time.
UMCES Senior Faculty Research Assistant David Loewensteiner drops a CTD overboard. The oceanography instrument takes eight measurements per second, tracking conductivity, temperature and depth as it is lowered through the water. Connected to the ship with a cable, the CTD sends data to a laptop in the boat’s dry lab. We measure 2.04 mg/L of dissolved oxygen in surface water, and just 0.33 mg/L at 98 feet deep. Critters need concentrations of 5 mg/L or more to thrive; these are “classic dead zone” conditions.
Dead zones are bad for the Bay. Like animals on land, underwater critters need oxygen to survive. In a dead zone, immobile shellfish suffocate and those fish that can swim are displaced into more hospitable waters. “If you were a self-respecting fish and oxygen was [low], what would you do?” asked Bill Dennison, Vice President for Science Applications and Professor at UMCES. “Swim away.”
First reported in the 1930s, the appearance of the dead zone in the Bay is linked to our actions on land: as we replace forests with cities, suburbs and farms, we increase the amount of nutrients entering rivers and streams. This fuels the growth of algae blooms that lead to dead zones. “Hypoxia [or low-oxygen conditions] is driven by what we do on the watershed,” said UMCES Assistant Professor Jeremy Testa. “The Bay is naturally set up to generate hypoxia because of that [stratification] feature. That said… when there were no people here, there was not much hypoxia.”
While it is our actions on land that created the dead zone, it is our actions on land that can make the dead zone go away. Research has shown that certain pollution-reducing practices—like upgrading wastewater treatment plants, lowering vehicle and power plant emissions and reducing runoff from farmland—can improve the health of local rivers and streams. Scientists have also traced a decline in the duration of the dead zone from five months to four, which suggests that conservation practices gaining traction across the watershed could have very real benefits for the entire Bay.
To view more photos, visit the Chesapeake Bay Program Flickr page.
Images by E. Guy Stephens/Southern Maryland Photography. Captions by Catherine Krikstan.
Scientists expect the Chesapeake Bay to see an above-average dead zone this summer, due to the excess nitrogen that flowed into the Bay from the Potomac and Susquehanna rivers this spring.
Dead zones, or areas of little to no dissolved oxygen, form when nutrient-fueled algae blooms die and decompose. The latest dead zone forecast predicts an early-summer oxygen-free zone of 0.51 cubic miles, a mid-summer low-oxygen zone of 1.97 cubic miles and a late-summer oxygen-free zone of 0.32 cubic miles. This forecast was funded by the National Oceanic and Atmospheric Administration (NOAA) and is based on models developed at the University of Maryland Center for Environmental Science (UMCES) and the University of Michigan.
Dead zone size depends on nutrient pollution and weather patterns. According to the U.S. Geological Survey (USGS), 44,000 metric tons of nitrogen entered the Bay in the spring of 2014. This is 20 percent higher than last spring’s nitrogen loadings, and will influence algae growth and dead zone formation this summer.
Researchers with the Maryland Department of Natural Resources (DNR) and the Virginia Department of Environmental Quality (DEQ) will measure oxygen levels in the Bay over the next few months. While a final dead zone measurement is not expected until October, DNR biologists measured a larger-than-average low-oxygen zone on their June monitoring cruise, confirming the dead zone forecast.
Reducing runoff from farmland has lowered pollution in Maryland, Virginia and Pennsylvania waters, indicating a boost in on-farm best management practices could lead to improved water quality in the Chesapeake Bay.
In a report released earlier this year, researchers with the Chesapeake Bay Program, the University of Maryland Center for Environmental Science (UMCES) and the U.S. Geological Survey (USGS) use case studies to show that planting cover crops, managing manure and excluding cattle from rivers and streams can lower nutrient concentrations and, in some cases, sediment loads in nearby waters.
Excess nutrients and sediment have long impaired the Bay: nitrogen and phosphorous can fuel the growth of algae blooms and lead to low-oxygen dead zones that suffocate marine life, while sediment can cloud the water and suffocate shellfish. In New Insights: Science-based evidence of water quality improvements, challenges and opportunities in the Chesapeake, scientists make clear that putting nutrient- and sediment-reducing practices in place on farms can improve water quality and aquatic habitat in as little as one to six years.
Planting winter cover crops on farm fields in the Wye River basin, for instance, lowered the amount of nutrients leaching into local groundwater, while planting cover crops and exporting nutrient-rich rich poultry litter in the upper Pocomoke River watershed lowered the amount of nitrogen and phosphorous in the Eastern Shore waterway. In addition, several studies in Maryland, Virginia and Pennsylvania showed that when cattle were excluded from streams, plant growth rebounded, nutrient and sediment levels declined and stream habitat and bank stability improved.
Image courtesy Chiot's Run/Flickr
Earlier this week, U.S. Department of Agriculture Secretary Tom Vilsack named the Bay watershed one of eight “critical conservation areas” under the new Farm Bill’s Regional Conservation Partnership Program, which will bring farmers and watershed organizations together to earn funds for soil and water conservation.
Researchers at the University of Maryland Center for Environmental Science (UMCES) measured minimal changes in Chesapeake Bay health in 2013, once again giving the estuary a “C” in their annual Chesapeake Bay Report Card.
This grade was the same in 2012, up from a “D+” in 2011. The Bay Health Index was reached using several indicators of Bay health, including water clarity and dissolved oxygen, the amount of algae and nutrients in the water, the abundance of underwater grasses, and the strength of certain fish stocks, including blue crab and striped bass. Introduced in this year’s report card, the Climate Change Resilience Index will measure the Bay’s ability to withstand rising sea levels, rising water temperatures and other impacts of climate change.
UMCES Vice President for Science Applications and Professor Bill Dennison attributed the Bay’s steady course to local management actions. While pollution-reducing technologies installed at wastewater treatment plants have improved the health of some rivers along the Bay’s Western Shore, continued fertilizer applications and agricultural runoff have stalled improvements along the Eastern Shore, Dennison said in a media release.
Upgrading wastewater treatment technologies has lowered pollution in the Potomac, Patuxent and Back rivers, leading researchers to celebrate the Clean Water Act and recommend continued investments in the sewage sector.
Introduced in 1972, the Clean Water Act’s National Pollutant Discharge Elimination System permit program regulates point sources of pollutants, or those that can be pinpointed to a specific location. Because wastewater treatment plants are a point source that can send nutrient-rich effluent into rivers and streams, this program has fueled advancements in wastewater treatment technologies. Biological nutrient removal, for instance, uses microorganisms to remove excess nutrients from wastewater, while the newer enhanced nutrient removal improves upon this process.
Researchers with the University of Maryland Center for Environmental Science (UMCES) have linked these wastewater treatment technologies to a cleaner environment. In a report released last month, five case studies show that wastewater treatment plant upgrades in Maryland, Virginia and the District of Columbia improved water quality in three Chesapeake Bay tributaries.
The link is clear: excess nutrients can fuel the growth of algae blooms, which block sunlight from reaching underwater grasses and create low-oxygen dead zones that suffocate marine life. Lowering the amount of nutrients that wastewater treatment plants send into rivers and streams can reduce algae blooms, bring back grass beds and improve water quality.
In New Insights: Science-based evidence of water quality improvements, challenges and opportunities in the Chesapeake, scientists show that new technologies at Baltimore’s Back River Wastewater Treatment Plant led to a drop in nitrogen concentrations in the Back River. Upgrades at plants in the upper Patuxent watershed led to a drop in nutrient concentrations and a resurgence in underwater grasses in the Patuxent River. And improvements at plants in northern Virginia and the District lowered nutrient pollution, shortened the duration of algae blooms and boosted underwater grass growth in the Potomac River.
Image courtesy Kevin Harber/Flickr
The Chesapeake Bay Program tracks wastewater permits as an indicator of Bay health. As of 2012, 45 percent of treatment plants in the watershed had limits in effect to meet water quality standards. But a growing watershed population is putting increasing pressure on urban and suburban sewage systems.
“Further investments in [wastewater treatment plants] are needed to reduce nutrient loading associated with an increasing number of people living in the Chesapeake Bay watershed,” New Insights notes.
Pollution-reducing practices can improve water quality in the Chesapeake Bay and have already improved the health of local rivers and streams, according to new research from the Chesapeake Bay Program partnership.
In a report released today, several case studies from across the watershed show that so-called “best management practices”—including upgrading wastewater treatment technologies, lowering vehicle and power plant emissions, and reducing runoff from farmland—have lowered nutrients and sediment in local waterways. In other words, the environmental practices supported under the Clean Water Act, the Clean Air Act and the Farm Bill are working.
Excess nutrients and sediment have long impaired local water quality: nitrogen and phosphorous can fuel the growth of algae blooms and lead to low-oxygen “dead zones” that suffocate marine life, while sediment can block sunlight from reaching underwater grasses and suffocate shellfish. Best management practices used in backyards, in cities and on farms can lower the flow of these pollutants into waterways.
Data collected and analyzed by the Bay Program, the University of Maryland Center for Environmental Science (UMCES) and the U.S. Geological Survey (USGS) have traced a number of local improvements in air, land and water to best management practices: a drop in power plant emissions across the mid-Atlantic has led to improvements in nine Appalachian watersheds, upgrades to the District of Columbia's Blue Plains Wastewater Treatment Plant have lowered the discharge of nutrients into the Potomac River and planting cover crops on Eastern Shore farms has lowered the amount of nutrients leaching into the earth and reduced nitrate concentrations in groundwater.
“In New Insights, we find the scientific evidence to support what we’ve said before: we are rebuilding nature’s resilience back into the Chesapeake Bay ecosystem, and the watershed can and will recover when our communities support clean local waters,” said Bay Program Director Nick DiPasquale in a media release.
But scientists have also noted that while we have improved water quality, our progress can be overwhelmed by intensified agriculture and unsustainable development, and our patience can be tested by the “lag-times” that delay the full benefits of restoration work.
“This report shows that long-term efforts to reduce pollution are working, but we need to remain patient and diligent in making sure we are putting the right practices in place at the right locations in Chesapeake Bay watershed,” said UMCES President Donald Boesch in a media release. “Science has and will continue to play a critical role informing us about what is working and what still needs to be done.”
UMCES Vice President for Science Applications Bill Dennison echoed Boesch’s support for patience and persistence, but added a third P to the list: perspiration. “We’ve got to do more to maintain the health of this magnificent Chesapeake Bay,” he said.
“We’ve learned that we can fix the Bay,” Dennison continued. “We can see this progress… and it’s not going to be hopeless. In fact, it’s quite hopeful. This report makes a good case for optimism about the Chesapeake Bay.”
The reduction of power plant emissions in the mid-Atlantic has improved water quality in the Chesapeake region, according to new research from the University of Maryland Center for Environmental Science (UMCES).
Image courtesy haglundc/Flickr
Researchers at the university’s Appalachian Laboratory have traced improvements in the water quality trends of nine forested watersheds located along the spine of the Appalachian Mountains to the Clean Air Act’s Acid Rain Program. Passed in 1990, the Acid Rain Program led to a 32 percent drop in human-caused nitrogen-oxide emissions in 20 states. As these emissions have declined, so too has the amount of nitrogen found in some Pennsylvania, Maryland and Virginia waterways.
In other words, while the Acid Rain Program only intended to reduce the air pollution that causes acid rain, it had the unintended consequence of reducing the amount of nitrogen oxide particles landing on the region’s forests, thus improving local water quality.
“Improvements in air quality provided benefits to water quality that we were not counting on,” said UMCES President Donald Boesch in a media release.
Once nitrogen oxide particles are emitted into the air, wind and weather can carry them long distances. In time, these particles fall onto the land or into the water. Nitrogen that enters rivers and streams can fuel the growth of algae blooms, which block sunlight from reaching underwater grasses and create low-oxygen “dead zones” that suffocate marine life. Scientists estimate that just over one-third of the nitrogen polluting the Bay comes from the air.
For almost two decades, state and federal partners have worked to rebuild Poplar Island in the Maryland waters of the Chesapeake Bay. Once home to a sawmill, a general store and a schoolhouse, the island succumbed to sea level rise, shrinking to a fraction of its size by 1996. Rebuilt using sand and sediment dredged up from the bottom of the Bay and hand-planted with native marsh grass, the island has become a refuge for 175 species of shorebirds, songbirds, waterfowl and raptors.
Eastern bluebirds, black ducks and snowy egrets are among the birds that nest on Poplar Island, but it is the osprey whose presence stands out. Their sprawling nests can be found on wooden platforms, abandoned barges and Bay-side rip-rap. Plentiful food and nesting space mean Poplar’s osprey population is healthy, and can give researchers like Rebecca Lazarus an idea of what the birds should look like under the best environmental circumstances.
Working with the U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (USFWS), Lazarus is studying contaminant exposure in osprey around the Bay. Because the birds sit at the top of the food chain, their health is an indicator of environmental problems. Tracking the buildup of chemical compounds in the eggs and blood of birds that Lazarus calls a “sentinel species” can tell us what toxics are present in our rivers and streams.
Lazarus started her season of research when ospreys returned to the Bay in mid-March. The University of Maryland doctoral candidate and USGS employee visited nests, counted eggs and watched the ospreys grow.
Once the chicks hatched, Lazarus used motion-activated game cameras to monitor their diets. The birds on Poplar eat almost exclusively striped bass and menhaden, reminding us that the management of these two fisheries has a big impact on the balance of the Bay ecosystem.
As the chicks grew, Lazarus tagged each one of them with a metal band. She measured their weight and culmen length, and took samples of blood to test for chemical contaminants.
The last large-scale study of contaminant exposure in osprey was conducted close to a decade ago, and found elevated concentrations of polychlorinated biphenyls (or PCBs) and flame retardants in egg samples from the Anacostia and middle Potomac rivers. Lazarus hopes her updated research will show us what contaminants persist in the watershed, posing potential threats to wildlife and human health.
The birds on Poplar are healthy and serve as a benchmark against which Lazarus can compare those that nest in more polluted parts of the Bay. Ospreys experienced such a strong population boom after the United States banned the insecticide DDT and other contaminants that they are now nesting along urbanized waterways where dense development, wastewater treatment plants and the flow of pharmaceuticals and other new toxics into our water have concern about their potential to thrive.
By monitoring the link between clean water, contaminant-free fish and healthy osprey, Lazarus has taken a holistic approach to her research. Once published, her findings could help state and federal agencies develop plans to mitigate pollution or prioritize contaminants of concern. And they will help improve the environmental quality, ecosystem integrity and sustainability of the Bay.
To view more photos, visit the Chesapeake Bay Program Flickr page.
Images by Steve Droter and Olivier Giron.
Captions by Catherine Krikstan.
Scientists at the University of Maryland Center for Environmental Science (UMCES) have measured an improvement in Chesapeake Bay health, giving the estuary a “C” in its latest Chesapeake Bay Report Card.
Up from a “D+” in 2011, the Bay Health Index of 47 percent takes into account seven indicators of Bay health, including water clarity and dissolved oxygen; the amount of algae, nitrogen and phosphorous in the water; the abundance of underwater grasses; and the health of the benthic or bottom-dwelling community. While underwater grasses continued to decline, the rest of the indicators improved in 2012.
Image courtesy EcoCheck/Integration and Application Network
“I’m cautiously optimistic about the health of the Chesapeake Bay,” said UMCES Vice President for Science Applications and Professor Bill Dennison in a media release. “We are seeing progress in our efforts to reduce nitrogen and phosphorous levels. In addition, water clarity, which had been declining, has leveled out—and may even be reversing course.”
According to the report card, these improvements are due to a number of weather events. While excess rainfall can push nutrient and sediment pollution into rivers and streams, a dry summer in 2011 led to improvements in water clarity and dissolved oxygen and the favorable timing and track of Superstorm Sandy meant the storm did less damage to the Bay than some feared.
Learn more about the 2012 Chesapeake Bay Report Card.
An online mapping tool is now available to help resource managers and restoration partners rebuild oyster reefs in the Chesapeake Bay.
Released this month by the National Oceanic and Atmospheric Administration (NOAA), the Oyster Decision Support Tool displays a range of information relevant to oyster restoration, from historic reef boundaries and maps of the seafloor to the rate of oyster disease, death and spatfall on bars in Maryland waters.
Over the past two centuries, native oyster populations have experienced a dramatic decline as habitat loss, disease and historic over-harvesting have taken their toll. But by filtering water, forming aquatic reefs and feeding countless watershed residents, the bivalves are an essential part of the Bay’s environment and economy.
But a new report from the University of Maryland Center for Environmental Science (UMCES) indicates that reef restoration could be more effective if paired with stronger harvest limits.
“Oysters should be able to come back if we help them out by reducing fishing pressure and improving their habitat,” said Michael Wilberg, Associate Professor at the UMCES Chesapeake Biological Laboratory, in a news release.
Dredging and tonging for oysters can damage reefs, pushing oysters onto unsuitable soft-bottom habitat or making them more vulnerable to suffocating sediment. According to the Wilberg-led study, if oysters were allowed to reproduce naturally and fishing were halted, it would take just 50 to 100 years for oyster abundance to reach as high a level as the Bay could support.
Learn more about the oyster population study.
Dead zones, or areas of little to no dissolved oxygen, form when nutrient-fueled algae blooms die. As bacteria help these blooms decompose, they suck up oxygen from the surrounding waters. The resulting hypoxic or anoxic conditions can suffocate marine life.
The Chesapeake Bay Program tracks dissolved oxygen as an indicator of water quality and Bay health.
The latest NOAA-funded forecast from researchers at the University of Maryland Center for Environmental Science (UMCES) and the University of Michigan predicts an average summer hypoxic zone of 1.108 cubic miles, lower than last year’s mid-summer hypoxic zone of 1.45 cubic miles.
This predicted improvement should result from the lower than average nutrient loads that entered the Bay this spring. According to the U.S. Geological Survey (USGS), 36,600 metric tons of nutrients entered the estuary from the Potomac and Susquehanna rivers, which is 30 percent lower than average.
The Bay’s dead zones are measured at regular intervals each year by the Maryland Department of Natural Resources (DNR) and the Virginia Department of Environmental Quality. While the final dead zone measurement will not take place until October, DNR biologists measured better than average dissolved oxygen on its June monitoring cruise, confirming the dead zone forecast.
A recent assessment of Superstorm Sandy shows the hurricane did less damage to the Chesapeake Bay than some feared, thanks in large part to its timing and track.
According to a University of Maryland report, the late-October hurricane whose path traveled north of the Bay had “ephemeral” impacts on Bay water quality—especially when compared to past storms.
The summertime arrival of Tropical Storm Agnes in 1972, for instance, coincided with a critical growing period for oysters, crabs and underwater grasses, and had a damaging effect on all three. But because Sandy arrived in the fall, the nutrients and sediment that it sent into the Bay were unable to fuel harmful algae blooms or damage the underwater grasses that had already begun to die back for the season. And while Tropical Storm Lee in 2011 brought heavy rainfall and a large plume of sediment to the Susquehanna River, the bulk of Sandy’s rainfall was concentrated elsewhere, meaning minimal scouring of sediment from behind the Conowingo Dam and “virtually no sediment plume” in the Upper Bay.
These findings echo those released in November by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS).
Read more about the ecological impacts of Sandy on the Chesapeake Bay.
The University of Maryland has received close to $700,000 in federal funding to help communities reduce stormwater runoff.
Using a software program to pinpoint pollution hot spots and an innovative brand of social marketing to boost citizen engagement, the university will embark on a multi-year project to increase the adoption of conservation practices in two watershed communities: the Wilde Lake watershed in Howard County, Md., and the Watts Branch watershed in Washington, D.C., whose waters flow into the Patuxent and Anacostia rivers, respectively.
Stormwater runoff, or rainfall that picks up pollutants as it flows across paved roads, parking lots, lawns and golf courses, is the fastest growing source of pollution into the Chesapeake Bay. Best management practices can reduce the flow of stormwater into creeks, streams and rivers, from the green roofs that trap and filter stormwater to the permeable pavement that allows stormwater to trickle underground rather than rush into storm drains.
But best management practices cannot work without the citizens who put them into action.
"We need to work with communities, rather than take a top-down approach [to stormwater management]," said project lead and assistant professor Paul Leisnham. "For the long-term successful implementation of these practices ... we need communities to be involved."
The university has partnered with local schools, religious organizations and grassroots associations (among them the Maryland Sea Grant, the Anacostia Watershed Society and Groundwork Anacostia) in hopes of breaking down barriers to the adoption of best management practices and increasing community involvement—and thus, investment—in local, long-term environmental conservation.
From left, U.S. Senator Ben Cardin, University of Maryland assistant professor Paul Leisnham and U.S. EPA Region 3 Administrator Shawn M. Garvin
U.S. Senator Ben Cardin commended the project at a Bladensburg Waterfront Park event as a creative and results-driven way to reduce stormwater runoff.
"It's going to allow us to make a difference in our [local] watershed, which will make a difference in the Chesapeake Bay," Cardin said.
The funding, which totaled $691,674, was awarded through the Sustainable Chesapeake Grant program administered by the U.S. Environmental Protection Agency.
An unusual sequence of weather events, including a wet spring, a hot, dry summer, and two tropical storms, caused the Chesapeake Bay’s health to decline in 2011, according to the University of Maryland Center for Environmental Science (UMCES) and the National Oceanic and Atmospheric Administration (NOAA).
(Image courtesy Chesapeake EcoCheck)
Scientists gave the Bay a D+ on the latest Chesapeake Bay Report Card, an annual assessment of the health of the Bay and its tidal rivers. The score of 38 percent was the second lowest since assessments began in 1986 and down from a C- in 2010.
Only two areas – the lower western shore and the Patapsco and Back rivers – improved last year. The rest of the Bay’s segments remained the same or got worse. Scientists recorded lower scores in the Patuxent River, Rappahannock River, James River, Tangier Sound, and the upper and middle Bay.
"The spring rains and hot, dry summer followed by Tropical Storm Lee and Hurricane Lee led to poor health throughout Chesapeake Bay and its tributaries," said Dr. Bill Dennison of the University of Maryland Center for Environmental Science. "While we have been making considerable progress in various restoration activities, these results indicate we still need to do much more to reduce the input of nutrients and sediments from stormwater runoff into the Bay."
The Bay’s health is largely affected by weather conditions. Rainfall carries pollution from farms, cities and suburbs to storm drains, streams and eventually the Bay. Even as the government, communities and citizens work to reduce pollution, an increase in stormwater runoff can mask the effects of these improvements.
Wet weather last spring washed more nutrient pollution into the water, fueling the growth of algae blooms that blocked sunlight from reaching bay grasses. Hot, dry weather allowed these algae blooms to persist through summer, leading to low-oxygen “dead zones” in the Bay’s bottom waters. In late summer, the Bay was slammed by the effects of Hurricane Irene and Tropical Storm Lee, both of which worsened water clarity.
"The report card clearly indicates that the Chesapeake Bay watershed is a dynamic ecosystem subject to severe weather events," said Bay Program Director Nick DiPasquale. “The silver lining is that the Hopkins-UMCES study of 60 years of water quality data concluded that a decrease in the frequency and severity of dead zones in the Bay is the direct result of implementing measures to reduce nitrogen and phosphorus pollution. We know what works; we just need to do more of it."
The Chesapeake Bay Report Card, produced by the EcoCheck partnership, offers a timely and geographically detailed assessment of the health of the Bay’s water quality and aquatic life. Visit EcoCheck’s website for more information about the report card, including region-specific data and downloadable graphics.
A new study analyzing 60 years of water quality data shows that efforts to reduce pollution from fertilizer, animal waste and other sources appear to be helping the Chesapeake Bay’s health improve.
The study, published in the Nov. 2011 issue of Estuaries and Coasts, was conducted by researchers from The Johns Hopkins University and the University of Maryland Center for Environmental Science (UMCES).
The research team found that the size of mid- to late-summer low oxygen areas, called “dead zones,” leveled off in the Bay’s deep channels during the 1980s and has been declining ever since. This is the same time that the Bay Program formed and federal and state agencies set the Bay’s first numeric pollution reduction goals.
“This study shows that our regional efforts to limit nutrient pollution may be producing results,” said Don Boesch, president of the University of Maryland Center for Environmental Science. “Continuing nutrient reduction remains critically important for achieving bay restoration goals.”
The study also found that the duration of the dead zone – how long it persists each summer – is closely linked to the amount of nutrient pollution entering the Bay each year.
For more information about the dead zone study, visit UMCES’s website.
The University of Maryland won top honors at the U.S. Department of Energy Solar Decathlon 2011 by designing, building and operating a solar-powered model house that helps reduce pollution to the Chesapeake Bay.
The house, named “WaterShed,” is a model of how development can help preserve the health of waterways like the Chesapeake Bay by managing stormwater runoff onsite, filtering pollution from greywater and minimizing overall water use. The house also includes solar features that make it less dependent on fossil fuels.
The Department of Energy deemed WaterShed the most cost-effective, attractive and energy-efficient house during the Solar Decathlon, held on the National Mall on Oct. 1.
The Solar Decathlon is a two-year project that challenges college students from around the world to design, build and operate solar-powered houses that are affordable, highly energy efficient, attractive and easy to live in.
Visit the WaterShed website to learn more about the winning house design.
Image courtesy Stefano Paltera/U.S. Department of Energy Solar Decathlon
A new study by researchers with the University of Maryland Center for Environmental Science recommends that Maryland place a moratorium on commercial oyster harvest from the Chesapeake Bay.
According to the study, Maryland’s oyster population is only 0.3 percent of what it was at its peak in the late 1800s. The population decline is due to a number of factors, including disease, pollution and overfishing.
The early summer dissolved oxygen forecast (called an “anoxia forecast”) is based on nitrogen loads to the Bay during winter and spring, as well as high river flow in May due to heavy rainfall. According to scientists, the Bay’s 2011 low-oxygen area – commonly called the “dead zone” – could be the fourth-largest since 1985.
The annual summer ecological forecast uses data such as nitrogen loads, wind direction and sea level to predict dissolved oxygen levels in the Bay’s mainstem. The forecast is split into early summer (June to mid-July) and late summer (mid-July to September) because scientists have observed a significant change in oxygen levels following early summer wind events.
The forecast is supported through research at the Chesapeake Bay Program, Johns Hopkins University, Old Dominion University, and the University of Maryland Center for Environmental Science Horn Point Lab.
For more information about the dissolved oxygen forecast, visit Chesapeake Eco-Check’s website.
The Chesapeake Bay has received a C-minus on the University of Maryland Center for Environmental Science’s (UMCES) 2010 Bay Health Report Card. The 2010 grade is a 4 percent decrease from 2009, when the Bay’s health received a C.
Higher rainfall – which led to increased stormwater runoff from the land – drove down scores for water quality and biological heath indicators. Researchers believe that two closely timed, large-scale weather events in winter 2010 played a role in the decrease.
The Bay’s health is affected by many factors, including human activities and natural variations in rainfall, which is the major driver of runoff from farms, cities and suburbs. Even as pollution is reduced, higher rainfall and associated runoff can mask the effects of these improvements.
“One of the main drivers of annual conditions in Chesapeake Bay is river flow related to weather patterns,” said UMCES-EcoCheck scientist Dr. Heath Kelsey. “While efforts to reduce pollution have been stepped up in recent years, nature overwhelmed those measures in 2010 and temporarily set the Bay back a bit.”
The declines are the first observed since 2003 and are on par with conditions observed in 2007. Annual weather-related variability in scores, even as more pollution-reduction measures are put into place, is to be expected in a highly complex ecosystem like the Bay, according to Dr. Kelsey.
Overall, the Lower Bay’s health score stayed relatively steady from 2009, while the Mid- and Upper Bay regions declined slightly. Results were fairly consistent in that declines were seen in most indicators.
The report card, based on data collected by state and federal agencies through the Chesapeake Bay Program, provides an independent analysis of Chesapeake Bay ecosystem health. It is expected that Bay Health Index scores will increase over time, as restoration and pollutant reduction activities are increased.
The report card analysis is conducted through the EcoCheck partnership between UMCES and the NOAA Chesapeake Bay Office. In addition to the Bay-wide reportcard, UMCES works with local watershed organizations to develop river-specific report cards to give residents a creek-by-creek look at their local waters.
For more information about the 2010 Chesapeake Bay Health Report Card, including region-specific data, visit the Chesapeake EcoCheck website.