In a watershed whose population has expanded by more than eight million people in the last 50 years, protecting land while allowing urban and suburban growth can pose a challenge. But one piece of Maryland’s land protection puzzle has proven successful in protecting forests and, according to some, could provide guidance to other regions interested in keeping trees on land that is threatened by residential development.
The Maryland Forest Conservation Act was passed under Governor William Donald Schaefer in late 1991 and implemented at the local level by county and municipal governments in 1993. It was designed to reduce forest loss following development and is the only statewide forest conservation regulation in the nation to focus on forest retention and replanting during the construction permitting process.
The Act affects those who propose land use changes on properties of one acre and greater in size and that require a subdivision approval, grading permit or sediment control permit: for example, a homeowner who wants to add a new residence to his property or a developer who wants to build a subdivision. These landowners must work with a licensed forester, licensed landscape architect or other qualified professional to submit their plans to protect trees during construction and to mitigate construction by retaining a portion of existing forest cover or by planting new trees.
By its nature as a required rather than optional regulation, the Act affects and engages a wide swath of landowners in planting trees and protecting land. “We’re more restrictive here [in Maryland than in other states] on what happens [to land] during development. There are a lot of environmental laws at the local level and at the state level that you need in order to get your building permits. Other states aren’t that way,” said Marian Honeczy, Urban & Community Forestry Programs Manager with the Maryland Forest Service.
Some landowners have argued against planting new trees when their proposed developments don’t involve removing them. But as Honeczy explains, the Act was meant to engage everyone in the work of environmental conservation. “Governor Schaefer felt that everyone should bear the burden of protecting the Bay, since we’re all sharing the benefits. It didn’t matter if you had a forested site or a farm field [slated for development]. Everyone had to comply with the law.”
That said, not everyone bears the same burden. Different zoning categories have different afforestation and reforestation thresholds and different forest retention amounts. In other words, those developing a farm field may have to plant fewer trees than those developing a woodlot. “But you’re still planting trees,” Honeczy said.
Healthy forests are critical to a healthy Chesapeake Bay: they protect clean air and water and provide food and habitat to wildlife. (For this reason, the Chesapeake Bay Program has committed to expanding urban tree canopy by 2,400 acres by 2025.) And for Honeczy, the Forest Conservation Act has “more than accomplished” its intended goal of conserving forests in the face of development. Indeed, research suggests the regulation has had a significant and positive effect on Maryland’s forest cover, and the numbers seem to agree: In the first 20 years of the Forest Conservation Act, 110,701 acres of forest land were put under protection from development. That area is two and a half times bigger than Washington, D.C.!
The Act does face challenges—in the form of finite land and finite funding—but it was “never intended to be the sole answer for all of our forest cover and urban tree issues,” Honeczy said. Just as protecting forests was not intended to be a burden on the shoulders of one landowner, it was also not intended to be a burden on the shoulders of one law, one program or one state agency.
Whether it is through the Woodland Incentive Program—which provides cost-share assistance for tree planting and timber stand improvement on forests between five and 1,000 acres in size—the Lawn to Woodland program—which fully funds the conversion of one- to four-acre lawns to forests—or the Marylanders Plant Trees program—which provides coupons to homeowners who want to purchase trees to plant—the Maryland Forest Service and their partners across the state will continue to connect anyone who wants to plant a tree with people and programs that will help them do so.
“Trees do so much in a cheap, efficient way to protect the Bay,” Honeczy said. “And every person can plant a tree on their property.”
The well-being of the Chesapeake Bay watershed will soon rest in the hands of its youngest residents. For many, efforts to instill in students a connection to the natural world—and in turn, a desire to care for it—begin with greening the buildings in which students learn. Whether by installing rain gardens and water bottle filling stations like Lanier Middle School in Fairfax, Virginia; turning an unused open-air space to a light-filled atrium like Woodrow Wilson High School in Washington, D.C.; or installing a geothermal heat pump and two thousand solar panels like Wilde Lake Middle School in Columbia, Maryland, schools across the region have made big strides toward sustainability.
Sustainable schools are built around reducing environmental impact, improving human health and strengthening environmental literacy. Because certification programs often require progress in each of these three pillars of sustainability, the benefits of sustainable schools are varied, from the conservation of water and energy to the improved test scores that have been linked to hands-on environmental education.
But building a sustainable school can take time and dedication on the part of principals, teachers and facilities staff. While the benefits of sustainable schools are proven—and outweigh costs 20 to 1—resources aren’t always distributed evenly and buy-in is not always easy to get.
“If a school administration does not understand the benefits of a sustainable school program and does not support teachers or other school staff investing time towards school sustainability, then it’s going to be difficult for any school to achieve it,” said Kevin Schabow, coordinator of the Chesapeake Bay Program’s Education Workgroup, which advances the partnership’s environmental literacy goals. “There are many priorities for administrators, and school sustainability may not be on their radar.”
That said, making a school sustainable can begin with grassroots enthusiasm. “Student voice is a powerful thing,” Schabow said. Whether the driver is a desire to compete with other schools or the knowledge that sustainable schools are good for staff and students alike, motivation can come in the form of a superintendent who encourages principals to go green, a teacher who excites students about stewardship or a group of students who lobby their principal for a change.
In the Chesapeake Bay watershed, a total of 502 public and charter schools—or 12 percent of all public and charter schools—are certified sustainable by one of the following programs: U.S. Green Ribbon Schools, Eco-Schools USA, Maryland Green Schools and Virginia Naturally Schools. Maryland is home to most of the sustainable schools in the region, in large part because their robust in-state program was established almost 20 years ago. Indeed, state-specific programs are not equal: in some states, these programs are robust; in others, these programs are not well-established; and in others, these programs do not yet exist. The Chesapeake Bay Program will continue to monitor sustainable schools in the region and provide support through funding and other means.
Schabow notes that the partnership’s sustainable school goal—which was adopted in the 2014 Chesapeake Bay Watershed Agreement and aims to continually increase the number of sustainable schools in the region—has increased awareness around the sustainable school initiative. “I’m hopeful that we can continue supporting state projects and see increased interest and participation in these programs,” Schabow said. “That’s really what we’re looking for. We’ve got the baseline [counted], but we want to see more.”
Learn more about our work to increase sustainable schools in the Chesapeake Bay watershed.
With more than 150,000 miles of riparian forest buffers growing in the Chesapeake Bay watershed, it’s clear that planting trees and shrubs along rivers and streams is a popular practice for protecting waterways. While it stands to reason that wide forest buffers could generate more benefits than narrow ones, it was not until 2014 that the Stroud Water Research Center set about to determine just how wide a buffer needed to be to work.
When Stroud Water Research Center President, Director and Senior Research Scientist Bernard W. Sweeney and Research Scientist J. Denis Newbold dove into research on forest buffer width, they were already decades into forest buffer history. In the seventies, wide zones of streamside vegetation were known to protect streams from the impacts of logging. In 1985, the sixth U.S. Farm Bill funded the planting of streamside vegetation to slow farmland erosion. And seven years later, research from Sweeney himself revealed the quality of streamside vegetation was likely the single most important human-altered factor affecting the structure, function and quality of our streams. But would width amplify all the benefits a forest buffer has to offer? And how wide is wide enough?
After examining eight ecosystem functions streams are known to support—including nutrient removal, sediment trapping and the health of macroinvertebrates and fish—Sweeney and Newbold found that the integrity of small streams can only be protected by forest buffers at least 30 meters—about 100 feet—wide. In other words, the ideal width of a forest buffer is only slightly shorter than three school buses laid end to end!
Of course, Sweeney and Newbold recognized the layout of a particular piece of land could limit the width of any forest buffers that may be planted there. The scientists also acknowledged forest buffer policies may need to accommodate site-specific factors. In the Chesapeake Bay watershed, a forest buffer must be at least 35 feet wide to count as a pollution-reducing practice that supports work toward the Bay’s “pollution diet.” Even so, the average forest buffer in the watershed is almost three times this size, and the benefits of a wide forest buffer are clear.
According to Sweeney and Newbold’s literature review, which synthesized the results of hundreds of scientific studies, effective nitrogen removal requires buffers that are at least 30 meters wide. Buffers of this size can also be expected to trap about 85 percent of any sediment delivered by water moving over the land (which is 30 percent more than a buffer only 10 meters wide!). A 30-meter width can also ensure a buffer protects streams from measurable increases in water temperature during summer months; sends a natural level of stems, branches and other large woody debris into a waterway; and supports natural macroinvertebrate and fish communities.
In our watershed, the planting and care of forest buffers can be limited by a lack of technical assistance and maintenance support. Indeed, buffer restoration has slowed in recent years. While the Chesapeake Bay Program has set a goal to restore 900 miles of buffers every year until at least 70 percent of the watershed’s riparian areas are forested, plantings continue to fall short of this annual target: last year saw the lowest restoration total of the last 16 years.
As part of our work to restore forest buffers, our partners have committed to increasing efforts to teach landowners about buffer establishment and care. Our partners have also committed to better tracking and spending technical assistance funds, seeking out additional funding for the suppression of interfering weeds and determining whether current payments that support buffer care should be raised.
Learn about our work to restore forest buffers.
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.
The Chesapeake Bay has more than 11,600 miles of shoreline. Evidence of its changing tides can be observed along much of the region, whether it is a high water mark on a dock piling, a line of seaweed on a beach or a shorebird pulling shellfish from the mud of a temporarily exposed flat.
In some watershed cities—like Annapolis, Maryland—the difference between high and low tides is about one foot. In others—like Norfolk, Virginia—this difference can reach up to three feet. We have built our roads, homes and buildings around the regular movement of this water. But as sea levels rise, land subsides and natural barriers to coastal flooding are lost, our coastal cities will face more impactful high-tide flooding that occurs regardless of heavy winds or rain.
High-tide flooding has also been called sunny-day, shallow coastal or nuisance flooding. The National Oceanic and Atmospheric Administration (NOAA) records a high-tide flood when one of its local tide gauges measures a water level above the local threshold for minor impacts. While the depth and extent of high-tide floods can vary, the nuisances that result are far from minor: disrupted transportation, degraded stormwater management systems, flooded roads, homes and businesses, and strained maintenance budgets.
Rates of high-tide flooding on all coasts are rising. In a June 2016 report on the state of high-tide nuisance flooding in the United States, NOAA researchers attribute increasing flood frequencies to local sea level rise—which itself is attributed to the melting of ice on land as the air warms and the expansion of seawater as oceans warm—and local land subsidence, or the settling or sinking of land. Indeed, according to the report, “annual flood rates have increased locally by two or three times or more as compared to the rate experienced 20 years ago.”
Of the 28 local long-term tide gauges operated by NOAA, four are in the Chesapeake Bay watershed. Together, these four cities—Annapolis and Baltimore in Maryland, Norfolk in Virginia and the District of Columbia—experienced a total of 128 high-tide flood days in 2015, with Baltimore and Norfolk experiencing local totals just two days and one day below the highest historical record. These floods were likely exacerbated by El Niño, which affected winds and storm tracks along the mid-Atlantic and West coasts.
The 2016 outlook for each of these four cities is lower than the number of flood days the cities observed in 2015: 15 flood days are expected to occur in 2016 in Baltimore, 47 in Annapolis, 33 in Washington, D.C., and 8 in Norfolk. However, NOAA expects future outlooks to underestimate flood days because of the increasingly “nonlinear response” flood frequencies will have to sea level rise. Furthermore, the agency’s high-tide flood outlook does not account for flooding compounded by local rainfall, and precipitation in the watershed is expected to increase in response to climate change.
While we cannot reverse the effects of climate change that have already been observed in the region—which include warming temperatures, rising sea levels and more extreme weather events, as well as coastal flooding, eroding shorelines and changes in the abundance and migration patterns of wildlife—we can enhance our resiliency against them. To build resiliency against high-tide flooding, for example, cities have relied on flood barriers to block rising water, drafted ambitious plans to raise low-lying streets and constructed new facilities higher off the ground.
Through the Chesapeake Bay Watershed Agreement, the Chesapeake Bay Program has committed to increasing the resiliency of the region’s communities, living resources and wildlife habitats to the adverse impacts of changing environmental conditions. Learn about our work to monitor and assess the trends and impacts of climate change and to pursue, design and construct restoration and protection projects that will enhance the resiliency of our ecosystem.
For more than a century, the United States has worked to protect the wilderness around us with parks, preserves and sanctuaries. While natural spaces of all shapes and sizes can benefit wildlife, only one government-designated wilderness program was established in order to build a network of wildlife habitat: the national wildlife refuge system.
The first national wildlife refuge was established in 1903. Today, there are more than 560 wildlife refuges in the nation, whose 150 million acres of land and water are managed by the U.S. Fish and Wildlife Service and marked with the emblem of a flying blue goose. Fifteen wildlife refuges are located in the Chesapeake Bay watershed, protecting forests, fields, ponds, marshes, swamps and shorelines in Maryland and Virginia. Federally owned land—which includes wildlife refuges—accounts for about 26 percent of the 8.37 million protected acres in the region, and is integral to our work to safeguard wildlife habitat from development. Learn about five wildlife refuges in the watershed below.
1. Eastern Neck National Wildlife Refuge (Rock Hall, Md.). Established in December of 1962, this 2,285-acre island refuge is located where the Chester River meets the Chesapeake Bay. The island was among the first parts of Maryland to be settled by European colonists: between 1658 and 1680, two men acquired the entire island tract by tract. Today, the island’s forests, grasslands, ponds and tidal marshes offer critical feeding and resting grounds to hundreds of species of migratory birds. Ducks, swans and geese are particularly abundant in late fall and early winter, and refuge staff have documented peaks of more than 50,000 waterfowl at one time on or near the refuge. The refuge provides visitors with opportunities to walk and bike, view wildlife, boat, fish, crab and hunt for turkey and white-tailed deer.
2. Patuxent Research Refuge (Laurel, Md.). Established in December of 1936, this refuge has expanded from its original 2,670 acres to encompass more than 12,800 acres between Baltimore and Washington, D.C. It is the only wildlife refuge established to support wildlife research. The Patuxent Wildlife Research Center is operated by the U.S. Geological Survey, whose staff specialize in research related to wildlife and natural resources science, from the status and trends of bird populations to the effects of chemical contaminants on wildlife. One of its most famous programs involves the captive breeding of whooping cranes: biological technicians raise more than 30 chicks each year, releasing most to a non-migratory flock in Louisiana and training the rest to migrate from Wisconsin to Florida. While the grounds that house the research center are not open to the public, the refuge’s North Tract and impressive National Wildlife Visitor Center provide visitors with opportunities to walk, view wildlife, fish and hunt.
3. Eastern Shore National Wildlife Refuge (Cape Charles, Va.). Established in 1984 to promote migratory and endangered species management, this 1,123-acre refuge located at the tip of the Delmarva Peninsula was once a military fort. During World War II, Fort John Custis protected naval bases in Virginia Beach and Norfolk. In 1950, the U.S. Air Force took ownership of the fort, renamed it the Cape Charles Air Force Station and occupied the area until 1981. Today, the refuge is valued as one of the most important stopover sites for migrating birds and butterflies in the nation. Each fall, songbirds, raptors and monarch butterflies gather at the refuge to feed and rest before resuming their migrations south. More than 400 bird species have been seen in and around the refuge, and on peak days, 100,000 monarch butterflies have been seen on refuge roosts. The refuge’s wood- and shrublands, fields, ponds and marshes are also valuable to insects (including the endangered northeastern beach tiger beetle), mammals and other critters. The refuge provides visitors with opportunities to walk, view wildlife, boat and hunt for white-tailed deer.
4. Elizabeth Hartwell Mason Neck National Wildlife Refuge (Lorton, Va.). Established in February of 1969, this 2,227-acre refuge sits on a boot-shaped peninsula between the Potomac and Occoquan rivers. While an airport and residential community were planned for the land in the early 1960s, local resident Elizabeth van Laer Speer Hartwell launched a campaign to halt the development and protect the bald eagles that called the Potomac River home. As a result, this refuge—located just 18 miles south of Washington, D.C.—became the first that was established for the explicit protection of the bald eagle and one of four named after women. It encompasses almost six miles of shoreline, 2,000 acres of mature hardwood forest and 207 acres of tidal freshwater marsh that is home to a large breeding colony of great blue herons. The refuge provides visitors with opportunities to walk, view wildlife and hunt for white-tailed deer.
5. Rappahannock River Valley National Wildlife Refuge (Warsaw, Va.). Established in 1996, this refuge is the newest of four that compose the Eastern Virginia Rivers National Wildlife Refuge Complex. While it currently consists of 8,720 acres of forests, grassland, marshland and swamps, the U.S. Fish and Wildlife Service hopes to protect 20,000 acres of habitat along the Rappahannock and its tributaries over time. The refuge is home to breeding bald eagles and migrating birds, and provides visitors with opportunities to walk, view wildlife, boat, fish and hunt for white-tailed deer.
As humans have shaped the world around us, we have ensured that lakes, rivers, oceans and even Arctic sea ice have something in common: these waters now contain microscopic pieces of plastic from our cosmetics, cleaners and synthetic clothing capable of harming the growth, development and behavior of marine life.
Known as microplastics, these debris are smaller than the width of a common drinking straw and are appearing in more regions and in bigger quantities around the world. In 2014, scientists reported the presence of microplastics in four Chesapeake Bay rivers: the Patapsco, Rhode, Corsica and Magothy. In 2015, scientists used a manta trawl to skim the surface of waters across the Bay and visually observed microplastics in many of the 60 samples that were taken.
The danger of microplastics is in their size, their makeup and the things that can happen to them once they are in the water. Microplastics are incredibly small and can be absorbed or ingested by a wide range of animals up and down the food chain. Microplastics are made from synthetic polymers that contain chemicals that can leach into the environment. And microplastics can “pick up” exotic organisms, pathogens and toxic contaminants and carry them over long distances. Research shows that microplastics have been ingested by hundreds of species—including some that we consume as food—and can affect the reproduction rate of zooplankton, the weight of benthic worms and the behavior of fish.
One kind of microplastic that has been the focus of media attention—as well as a successful movement to ban the item from personal care products—is the microbead: synthetic polymers that have replaced pumice, oatmeal and other natural exfoliants as abrasive scrubbers. Their fate is inherent in their design: many microbeads are meant to be washed down the drain, moving through wastewater treatment plants and into rivers and streams as direct effluent or as so-called “biosolids” applied to farm fields and pushed by rain or wind back into the water. In the United States alone, an estimated eight billion microbeads are released into aquatic habitats every day. Assuming these beads are 100 micrometer spheres—close to the diameter of a human hair—you can wrap them around the earth more than seven times.
Because microbeads are a significant source of microplastics, any effort to eliminate them removes a significant source of microplastics from the environment. In a technical review of microbeads and microplastics in the Chesapeake Bay, our Scientific and Technical Advisory Committee (STAC) called federal legislation to ban microbeads from rinse-off personal care products “laudable,” but found the regulations’ scope is too limited to address the whole microplastics—and even the whole microbead—problem.
As experts noted in the STAC report, a focus on rinse-off personal care products does not eliminate all sources of microbeads from the environment. Cosmetics, deodorants, lotions and non-personal care products like industrial and household cleaners aren’t addressed. So this legislation could be seen as the beginning of a suite of management strategies for microbeads and microplastics. To maintain momentum in the fight against microplastics, experts recommend improving techniques to detect the presence, composition and quantities of microplastics in the environment; initiating a long-term study on the amount, sources and sinks of microplastics in the Bay; improving waste management and promoting sustainable product design; and leading educational outreach and legislation on the topic.
As part of the Chesapeake Bay Program's work toward its Toxic Contaminants Research Outcome, partners have committed to gathering more information on microplastics and other issues of emerging concern. Learn about our efforts to combat microplastics and how you can help.
Many residents of the region know that pollutants in rivers like the James, Potomac and Susquehanna can end up in the Chesapeake Bay. In fact, the Chesapeake Bay watershed—or the area of land over which water flows into the nation’s largest estuary—stretches from Cooperstown, New York, to Norfolk, Virginia. Less well known is the fact that the Bay’s so-called “airshed” extends much farther: particles of air pollution emitted as far away as Cincinnati, Ohio, can reach the waters of the Bay.
At 570,000 square miles, the Bay’s airshed is nine times as large as its watershed. Because pollution emitted into the air can be carried over long distances by wind and weather, it should come as no surprise that emissions associated with hydraulic fracturing operations in Pennsylvania and West Virginia have been found in Baltimore, Maryland, and Washington, D.C., or that emissions from gas, coal and oil-powered machines in Tennessee or North Carolina can lead to algae blooms in the waters of Maryland and Virginia.
Scientists estimate that one-third of the total nitrogen that pollutes the Bay comes from the air, often in the form of nitrogen oxides generated by power plants or machines. Through a process known as atmospheric deposition, six to eight percent of this airborne nitrogen falls onto the water directly, sometimes as dry particles and sometimes attached to raindrops, snowflakes or sleet. The rest falls onto the land, where it soaks into groundwater or washes into rivers and streams. Once in the water, nitrogen can fuel the growth of harmful algae blooms that create low-oxygen dead zones that suffocate marine life.
But there is evidence that regulations meant to curb air pollution are having a positive impact on our air and our water. In 2014, for instance, researchers with the University of Maryland Center for Environmental Science traced a drop in the amount of nitrogen found in some Maryland, Pennsylvania and Virginia waterways to the Clean Air Act. In 2015, the U.S. Environmental Protection Agency declared the drop in the atmospheric deposition of nitrogen observed in the region over the past two decades can also be attributed to the Clean Air Act. And in 2016, our own water quality modeling experts confirmed we are still seeing benefits of the Clean Air Act emerge as estimates of the atmospheric deposition of nitrogen continue to fall.
This means efforts to curb air pollution across the nation have curbed water pollution in our watershed. In 1985, an estimated 52.2 million pounds of nitrogen fell directly onto the region’s waters. Thirty years later, this number has dropped to 17.88 million pounds, and data show that pollution-reducing practices put in place between 2009 and 2015 in an effort to meet the Bay’s “pollution diet” have reduced the atmospheric deposition of nitrogen 20 percent.
Less than 15 years ago, an exotic green beetle was discovered in southeastern Michigan. In the years that followed, the metallic insect that is no more than half an inch long spread into 24 more states—including five in the Chesapeake Bay watershed—and now threaten millions of native ash trees that fall sick and die when the insect’s larvae feed on the tissue underneath their bark.
The emerald ash borer likely arrived in the United States on wood packing material carried on airplanes or cargo ships from its native China. While the insects can fly at least half a mile from where they emerge as adults, it is the movement of larvae-laden wood that is thought to be the cause of many emerald ash borer infestations. As a result, the shipment of ash trees and logs is regulated, and transporting firewood outside of quarantined areas is illegal.
Such precautions are necessary because of the impact the emerald ash borer can have on forests. As larvae feed on the nutrient-rich inner bark of ash trees, they disrupt the trees’ ability to move food and water from its roots to its leaves. Once a tree is infested with emerald ash borer larvae, one-third to one-half of its branches may die within a year. Most of its canopy may be dead within two years, with the entire tree dead in three to four.
Ash trees can be found in almost all parts of the United States. All North American ash trees are susceptible to infestation, which means countless forests are susceptible to the loss of a species that supports the ecosystem’s protection of clean air, water and wildlife habitat. While native trees could fill the gaps left by dead ash, invasive plants could also spread in response to new light levels. Even the makeup of the surrounding soil may change, as ash trees are “dynamic accumulators” that gather calcium from the soil around them.
The economic impacts of the emerald ash borer are significant. First, there are costs to losing trees. The U.S. Forest Service estimates the eight billion ash trees on U.S. timberlands to be valued at $282.25 billion. Then, there are costs to mitigating the damage the insect has done. The Forest Service has predicted that an expanding infestation through 2019 will warrant the treatment, removal and replacement of more than 17 million ash trees, with an estimated price tag of $10.7 billion.
But the Forest Service has also explored an impressive number of emerald ash borer control and management methods. Experts have searched for effective predators, parasitoids and pathogens that could act as biological controls, evaluated the efficacy of insecticides injected into trunks of infested trees and explored the development of genetic hybrids that would integrate the resistance of Asian ash tree species into those native to North America. Experts have also conducted research into ridding trees of larvae by submerging infested logs under water, treating infested logs with chemicals and removing the bark of infested logs that could otherwise be sent to sawmills and manufacturing plants to be used for lumber, railroad ties and other value-added products.
In light of the extensive research that has been done in the years since the emerald ash borer was first found in the United States, the most important thing for individuals to remember is to follow regulatory guidelines for moving ash trees, logs and firewood and to report potential infestations to your local Cooperative Extension Service office. According to the Forest Service, making a large investment in understanding and controlling the spread of this invasive insect now could slow the expansion and postpone the ultimate costs of the emerald ash borer.
Each winter, the mid-Atlantic receives an average of 23 inches of snow. To combat the flakes that freeze on roads and slow drivers down, states spread road salt on highly traveled highways. While removing ice and increasing tire traction is critical to keeping drivers safe during snowstorms, the most commonly used road salt can have adverse effects on the surrounding environment.
According to the Chesapeake Stormwater Network, between 10 and 20 million tons of road salt—the most common form of which is sodium chloride—are applied to the nation’s highways each year. About a third of this is applied to states in the mid-Atlantic, and stormwater professionals estimate that 2.5 million tons of road salt are applied annually across the Chesapeake Bay watershed. While a Chesapeake Bay Commission review of regional road salt policies found that the indiscriminate application of road salt does not typically occur in Maryland, Virginia or Pennsylvania, evidence shows that chloride concentrations in Maryland’s freshwater streams have increased over the last 40 years because of salt accumulation.
Because sodium chloride dissolves in water, it enters streams easily when surrounding snow melts. Small streams located close to treated roads are disproportionately affected by road salt and suffer notable chloride spikes each winter. While streams that are considered freshwater typically contain less than 300 mg of chloride per liter—and the U.S. Environmental Protection Agency has recommended long-term chloride exposure fall under 230 mg per liter in freshwater streams—a paper published in the Proceedings of the National Academy of Sciences shows that urban streams in the mid-Atlantic can contain five to ten times that amount.
What does this mean for streams and the critters that call them home? A literature review from the Maryland Department of the Environment notes that malformations among green frogs and mortality among spotted salamanders rise with exposure to road salt. High chloride levels can also lower the variety and abundance of fish in a waterway and cause those fish that are left to eat less and exhibit slower growth. And while some bottom-dwelling macroinvertebrates—whose presence is a key indicator of stream health—can withstand elevated chloride concentrations, long-term exposure is harmful. In Maryland, Index of Biotic Integrity scores—which rank stream health on a five-point scale—appear to decline as chloride concentrations increase, indicating road salt could be at least partially responsible for the “impaired” listings of certain streams in the state.
What can be done? Because road salt is a clear contributor to the long-term salinization of streams in the region, the Maryland Department of the Environment recommends aggressively managing and, in some cases, limiting road salt use. States can set chloride concentration standards, for instance, while highway agencies can work to improve the storage and application efficiency of deicers. Individual homeowners can make sure to apply deicers when they will be most effective or use chemical alternatives.
Countless creeks, streams and rivers flow into the Chesapeake Bay. For decades, the U.S. Geological Survey (USGS) has measured the flow of the region’s rivers in order to forecast floods, spot low-flow conditions and estimate the amount of pollution running from the land into the water. While annual river flow has remained within its normal range for much of the last decade, our increasingly variable climate has fostered increasingly variable river flow, which has the potential to affect habitats and pollution levels in the Bay.
While river flow is tracked at 300 monitoring stations across the watershed, it is the data that are collected at stations along its three biggest rivers—the Susquehanna, the Potomac and the James—that are used to calculate total flow into the Bay. Data collected at these monitoring stations show that, on average, 51 billion gallons of water flow into the Bay each day.
Annual river flow that falls between 44 and 58 billion gallons per day is considered normal. But the last 15 years have seen extreme flow variability, which can affect the surrounding ecosystem.
While low river flow can dry up stream beds and threaten fish, high river flow has garnered much attention in the region.Excess river flow can damage stream banks, trigger sewage overflows and push pollutants—including nutrients, sediment and toxic contaminants picked up from farm fields, backyards, parking lots and roads—into the Bay. It can also lower salinity levels in the Bay itself, which has a direct impact on underwater grasses, fish and shellfish. Often, high river flow is linked to heavy precipitation, which has become a noted impact of our changing climate.
In 2014, the U.S. Global Change Research Program reported in its National Climate Assessment that heavy downpours have increased across the nation. The Northeast, in particular, has seen a 71 percent rise in the amount of precipitation that falls during heavy downpours: a higher jump than any other region in the United States. In our work to protect the nation’s largest estuary, the Chesapeake Bay Program is taking these and other climate impacts into account.
Through the Chesapeake Bay Watershed Agreement’s climate resiliency goal, our partners have committed to monitoring climate trends and the effectiveness of our restoration policies, programs and projects under these changing conditions. Our partners have also committed to adjusting our work as needed in order to enhance the resiliency of the watershed against climate change. Because in building the resiliency of the Bay, we can increase the likelihood that its living resources, habitats, public infrastructure and communities will withstand the changes—to temperature, sea level and even river flow—that may come their way.
With its rough shell, gray body and big ecological value, the eastern oyster is one of the most iconic species in the Chesapeake Bay. And for decades, protecting oyster populations has been part of the Chesapeake Bay Program’s work. But it was not until the signing of the Chesapeake Bay Watershed Agreement that our partners committed to what is known as a tributary-based restoration strategy, setting a goal to restore oyster reefs in ten Maryland and Virginia rivers by 2025 in order to foster the ecological services these reefs provide.
In Maryland, three tributaries—often referred to collectively as the Choptank Complex—have been selected for oyster reef restoration, which will take place where oyster harvest doesn’t occur. While the implementation of restoration treatments in Harris Creek was completed this September, work remains in two other waterways that flow into the Choptank. According to a December update from our Sustainable Fisheries Goal Implementation Team, 589 acres of oyster reefs are targeted for restoration in the Little Choptank and Tred Avon rivers. That’s an area bigger than the town of Oxford, Maryland, which is located between the two waterways.
But what does restoring reefs to a tributary entail? The process varies by state and even by waterway. While its overarching steps—from selecting a tributary and setting a target to tracking progress and monitoring oyster health—are often the same, a range of factors can impact the specific course of work. The availability of shell and other hard substrates (which are used to build reefs) and the availability of spat (which are planted on reefs) are of particular concern in a region where both resources are used for other work (including aquaculture and shellfish harvest).
Nevertheless, work is underway in the Little Choptank and Tred Avon. In the Little Choptank, which has a restoration target of 442 acres, 114 acres have been built and 35 have been seeded with spat to date. In the Tred Avon, which has a restoration target of 147 acres, 17 have been built and just over two and a half have been seeded to date. The next progress report from the Maryland Oyster Restoration Interagency Workgroup will be released in spring of 2016, and tributary teams in Virginia will continue their work in the Piankatank, Lafayette and Lynnhaven rivers. The two-year work plan detailing the steps that will be taken to restore reefs in Maryland and Virginia will be released in summer.
Update: On January 13, 2016, the Chesapeake Bay Journal reported that the state of Maryland has instituted a "brief pause" in its construction of oyster reefs in the Tred Avon River. Maryland Department of Natural Resources Secretary Mark J. Belton told the newspaper that the pause will be in place until the state completes an internal review of its oyster management policies, due in July.
With its attractive mix of forested uplands, tidal marshes and intertidal mud flats, beaches and manmade rocky shores, the Chesapeake Bay offers a wide range of habitats to waterbirds. Even in the dead of winter, the productivity and position of the nation’s largest estuary—which offers fish, grasses and aquatic invertebrates to eat and is located in the center of the Atlantic Flyway—make it a perfect place for those birds that depend on aquatic resources to take up residence. Indeed, according to a report from the Center for Conservation Biology, the Bay supports 87 species of waterbirds during winter months.
Of these wintering waterbirds, 14 species rely on the Bay to serve as habitat for more than 10 percent of their continental populations. Learn about five of these species below.
1. The canvasback (Aythya valisineria) is the largest species of diving duck, with a long, sloping profile and wedge-shaped head. Because the birds keep their breeding plumage for most of the year, males are often seen with chestnut-colored heads, black breasts and white wings, sides and bellies. Canvasbacks feed on the roots, leaves and buds of underwater grasses—with wild celery a favorite winter food—as well as snails, clams and other aquatic invertebrates. In 2015, researchers with the Maryland Mid-winter Waterfowl Survey recorded 64,200 canvasbacks along the state’s Bay shoreline and Atlantic coast. This is one of the state’s highest canvasback counts since the mid-1960s, and close to the survey’s 2014 estimate of 68,400 birds.
2. The horned grebe (Podiceps auritus) is a small, duck-like waterbird whose plumage is black and white during winter months. During the breeding season, it has black and chestnut plumage and two golden patches of feathers behind its scarlet eyes. It can raise and lower these “horns” at will, and these give the species its common name. Horned grebes can use their straight, stubby bills to pick insects out of the air or off of the water’s surface, but most often dive into the water to hunt for aquatic invertebrates.
3. The long-tailed duck (Clangula hyemalis) is a medium-sized diving duck that has been reported to forage for food at depths of up to 200 feet. In the Chesapeake Bay, however, the birds usually dive to depths of 25 feet to reach the plant matter, small fish and aquatic invertebrates on which it feeds. Male long-tailed ducks have two long and slender tail feathers—which give the species its common name—and often have a pink band near the tip of their black bills. The birds often swim in small groups within a large, loose gathering of several hundred individuals. In 2015, researchers with the Maryland Mid-winter Waterfowl Survey recorded 100 long-tailed ducks along the state’s Bay shoreline and Atlantic coast. This is the state’s lowest long-tailed duck count of the last five years, and continues the decline that has been recorded since 2012, when 800 birds were observed.
4. The ruddy duck (Oxyura jamaicensis) is one of the smallest ducks of the Chesapeake Bay. The chubby bird has a long, stiff tail—which it often holds upright—and a wide, gray bill—which on males turns blue in the summer. Ruddy ducks dive into the water to search for aquatic plants and invertebrates and to seek refuge from predators, diving instead of flying when frightened. In 2015, researchers with the Maryland Mid-winter Waterfowl Survey recorded 20,000 ruddy ducks along the state’s Bay shoreline and Atlantic coast. This is just below the state’s short-term average ruddy duck count.
5. The Atlantic brant (Branta bernicla) is a small goose with a small, black head; short, black bill and neck; white necklace; and light gray belly. Brants graze on land, dip their heads underwater and upend their whole bodies to feed on aquatic plants and invertebrates. Eelgrass is a favorite food and staple of their diet. In 2015, researchers with the Maryland Mid-winter Waterfowl Survey recorded 900 brants along state’s Bay shoreline and Atlantic coast. This is just below the state’s short-term average brant count.
Three centuries ago, the Chesapeake Bay watershed was covered with trees. Maples, pines and oaks captured rainfall, stabilized the soil and offered food, shelter and migration paths to wildlife. But as the country was settled and developed, more people moved into the region, and forests were cleared for farms and communities and trees were cut for timber and fuel. The population of the region now stands at almost 18 million—more than double what it was in the 1950s. While valuable forests do remain in the region, many suffer from fragmentation: separation into smaller pieces that are vulnerable to threats.
According to a report from the U.S. Forest Service, 60 percent of Chesapeake forests have been divided into disconnected fragments by roads, homes and other gaps that are too wide or dangerous for wildlife to cross. The isolated communities of plants and animals that result have smaller gene pools that make them more susceptible to disease. The sensitive species that thrive in the moderate temperatures and light levels of an “interior” forest (which is mature and separate from other land uses) can’t find the unique habitat characteristics they need. And the forests themselves are more vulnerable to invasive species and other threats.
In an effort to reconnect fragmented forests, conservationists have turned to wildlife corridors. These corridors give wildlife the space to move and can be found around the world. The World Wildlife Federation runs the Freedom to Roam initiative to protect corridors along the Northern Great Plains and Eastern Himalayas. The National Wildlife Federation runs the Critical Paths Project to cut the number of fatal road crossings for animals in Vermont. And watershed states like Maryland and Virginia have incorporated wildlife corridors into their green infrastructure plans.
Even local landowners have contributed to the corridor movement: in September, the Alliance for the Chesapeake Bay recognized Christine and Fred Andreae as Exemplary Forest Stewards for their work to manage 800 acres of forestland—including a corridor that connects George Washington National Forest and Shenandoah National Park—along the Page and Warren county lines in Virginia.
Christine and Fred placed the property under conservation easement through the Virginia Outdoors Foundation, which was established by the Commonwealth in 1966. The Andreaes have also convinced their neighbors to follow suit: what started as an agreement between Christine, Fred and one neighbor to connect a patch of land on two sides of the Shenandoah River eventually expanded to include eight property owners and 1,750 contiguous acres. Today, bald eagles and bears abound on the land that can be seen from Skyline Drive.
“[Our neighbors] wanted to keep the land undeveloped,” Fred said when asked how he motivated others to join the conservation cause. “Most of them had family connections to the land—some [spanning] 100 years or more. It was their heritage they wanted to see preserved.”
The Andreaes have made their property as self-sustaining as possible so that once their two sons inherit it, it won’t have to be sold. “We’ve done something that will last. That’s a legacy. That will be there, theoretically, forever,” Fred said. “There aren’t too many things you can do that will be there after you’re gone—that will have an impact on my family and the other people who live in the area.”
Through the Chesapeake Bay Watershed Agreement, the Chesapeake Bay Program has committed to expanding urban tree canopy and restoring hundreds of thousands of miles of streamside trees and shrubs. Learn more about forests and our work to protect them.
Blue crabs are one of the most recognized and oft-consumed species in the Chesapeake Bay. Watermen harvest the olive green, eight-legged crustacean with trotlines and crab pots so tourists and watershed natives alike can eat them at bars, restaurants and paper-covered picnic tables all summer long. But despite continued demand, the commercial harvest of blue crabs has dropped by two-thirds over the last two and a half decades.
Since 1990, commercial watermen have harvested more than 1.6 billion pounds of blue crabs from the Bay. Data show commercial harvest has experienced a steady decline, and last year hit the lowest level recorded in 25 years: 35 million pounds.
Why was harvest so low? “A combination of factors,” said Chesapeake Bay Stock Assessment Committee Coordinator Emilie Franke. One factor that often affects harvest is the set of regulations put in place to conserve the population. Last season, Maryland, Virginia and the Potomac River Fisheries Commission responded to relatively low blue crab abundance by putting additional commercial harvest regulations in place. But these regulations alone do not determine harvest levels. Low crab abundance can also lower harvest, making it harder for crabbers to catch crabs in the first place. In other words, the explanation could lay in the blue crab population and the host of factors that affect it.
The Chesapeake Bay Stock Assessment Committee (CBSAC) brings together scientists and representatives from the federal government, state governments and academic institutions. It meets each year to review the results of blue crab surveys and develop management advice.
“Chesapeake Bay blue crabs were considered depleted in 2014 due to low female abundance," Franke said. "But jurisdictions have harvested below the female exploitation target for seven consecutive years. So there are obviously other factors at play affecting population and harvest levels. A lot of these factors are things fishery managers can't control."
On the list? Natural variability, water quality, habitat quality, predator and prey abundance, disease, competition and overwintering mortality, all of which affect the amount of blue crabs in the Bay. (Overwintering mortality affected all segments of the blue crab population in 2015, for instance, and led to an estimated 15 percent drop in overall abundance.)
Tracking these factors—including those we can control—is critical to blue crab management. This is one reason accurate harvest reporting is so important. In its annual report on the status of the blue crab population, CBSAC recommended continued improvement in the quality of catch and fishing effort information submitted by commercial and recreational harvesters. Jurisdictions have explored new harvest technologies in recent years, and the Chesapeake Bay Watershed Agreement includes a commitment to improve harvest accountability.
The state of Maryland’s electronic harvest reporting pilot program is an example of new harvest reporting technology in action. While traditional paper-based reporting can be inefficient and prone to errors, electronic reporting can provide more timely, accurate and verifiable information to fishery managers.
“Increased harvest accountability provides managers with an accurate picture of the fishery, which helps inform future management decisions,” Franke said. “Getting a better understanding of catch and fishing effort is a big priority.”
In the rivers and streams of Pennsylvania, you can find channel catfish, small and largemouth bass, white perch and rainbow trout. But the persistence of toxic contaminants in the Delaware, Ohio and Susquehanna river basins has limited the amount of fish you can consume from the Commonwealth’s waters.
Mercury, polychlorinated biphenyls (PCBs) and other toxic contaminants pose risks across the United States. Toxics enter the environment through air pollution, agricultural and urban runoff, and wastewater discharged from industrial and municipal treatment plants. Toxics bind to sediment, build up in the tissues of fish and move through the food web through a process called bioaccumulation. Because of the health risks associated with the frequent consumption of fish affected by toxics—birth defects and cancer among them—Pennsylvania has advised people to consume no more than eight ounces of locally caught sport fish in a given week.
Pennsylvania isn’t the only state in the watershed coping with contaminants. According to data from the U.S. Environmental Protection Agency (EPA), 74 percent of the tidal Chesapeake Bay is partially or fully impaired by toxics. And all states in the watershed have issued fish consumption advisories as a result.
Of course, most fish consumption advisories aren’t meant to stop the consumption of all locally caught fish, unless Do Not Eat is shown in an advisory listing. Some people are more at-risk (pregnant and breast-feeding women, women of childbearing age, and children), and some fish are safer to eat (smaller, younger fish and those species that are not as fatty as their catfish, carp or eel counterparts). For most, the benefits of eating fish can be gained as long as you choose a safe place to fish, pick a safe species to eat, trim and cook your catch correctly, and follow recommended meal frequencies.
Through the Chesapeake Bay Watershed Agreement, the Chesapeake Bay Program has committed to reviewing the latest research on toxic contaminants and improving the practices and controls that would reduce their effects. Learn more about our efforts to further toxic contaminants research and policy and prevention.
Like animals on land, critters in the Chesapeake Bay need oxygen to survive. But persistent nutrient pollution—and the algae blooms that result—mean some fish and shellfish have a hard time finding the oxygen they need to survive and thrive.
Under water, oxygen is present in dissolved form. When nutrient-fueled algae blooms die, the bacteria that arrive to decompose them use up oxygen in the water, leaving little for fish and shellfish and creating so-called “dead zones.” Increased nutrient pollution leads to larger algae blooms, which in turn create more dead zones.
Scientists measure dissolved oxygen as part of their work to determine the health of an ecosystem. Because an animal’s size and habitat determine how much oxygen it needs, scientists have set different dissolved oxygen standards for different aquatic habitats at different times of the year. An American shad, white perch or other fish found in shallow water, for instance, needs more oxygen than a worm, clam, oyster or other invertebrate found on the Bay’s bottom. While the former thrive at dissolved oxygen concentrations of 5 milligrams per liter of water, the latter need just one. The Bay’s infamous blue crabs and oysters, on the other hand, need dissolved oxygen concentrations of three milligrams per liter to thrive.
According to recent data, between 2011 and 2013, 24 percent of the water quality standards for dissolved oxygen were met in the deep-water habitat where bottom-feeding fish, blue crabs and oysters are found. Because the Chesapeake Bay Program has set a goal to achieve the clean water necessary to support aquatic resources and protect human health, our partners are working to reduce pollution and bring the Bay up to water quality standards. Learn how you can help.
Each spring, migratory fish use the rivers and streams of the Chesapeake Bay watershed to move between fresh water and the saltier ocean. Anadromous species—like American shad, hickory shad and blueback herring—return from the ocean to lay their eggs in fresh water, while catadromous species—like the American eel—move from streams to the ocean to spawn. While dams and culverts can block the movement of these fish, dam removal and fish passage construction projects have reopened thousands of area stream miles to fish migration.
According to the Maryland Department of Natural Resources, 33 fish species have ascended a fish lift, ladder or other structure in the state. While this indicates the value of fish ladders, lifts and other structures that help move fish over dams, it’s important to note the shift that new research has brought to fish passage restoration.
“Our [fish passage] program has changed over the years,” said Nancy Butowski, who manages fish passage in Maryland and serves as a member of the Chesapeake Bay Program’s Fish Passage Workgroup. “In the 1990s, it was focused on providing fish passage through ladders. But…fish passages are not 100 percent efficient. Now, we prefer dam removal.”
Dam removal can benefit a wider range of species—like the resident fish who also move up and downstream at different times of year—and the stream itself, Butowski said. Depending on the dam, its removal can even benefit human health: there have been several deaths at the Patapsco River’s Bloede Dam, which is slated for removal.
Maryland has worked with Pennsylvania, Virginia and the Nature Conservancy to develop a tool that will prioritize fish passage restoration projects. It takes close to 40 different characteristics into account, including how many miles a project would open, how much a project would cost and whether there are migratory fish currently using the waterway. Through the Chesapeake Bay Watershed Agreement, the Bay Program has committed to reopening 1,000 more stream miles to migratory fish by 2025. Learn more about our work to reopen fish passage.