Underwater bay grasses covered 79,675 acres of the Chesapeake Bay and its tidal rivers in 2010, according to data from scientists with the Chesapeake Bay Program. This is a 7 percent decrease from 2009, when bay grasses covered 85,914 acres of the Bay’s shallows.
Despite the drop, the 2010 bay grass acreage estimate ranks as the third-highest Bay-wide acreage since 1984, when the annual survey began.
"Even with the decreases in the 2010 bay grass coverage, the patterns are similar to previous years,” said Lee Karrh, living resources assessment chief with the Maryland Department of Natural Resources and chair of the Bay Program's SAV Workgroup. “Many of the fresh and low salinity areas have very high abundances, including 16 that have reached their restoration targets. However, the saltier parts of the Bay continue to struggle, with most areas well below the restoration goals, with only the mouth of the James River exceeding the goal.”
Bay grass abundance is currently at 43 percent of the Bay Program’s 185,000-acre goal. This goal is based on approximate historic bay grass abundance from the 1930s to present.
“We were pleased that grasses remain healthy and abundant in two areas where nutrient pollution was reduced: the upper Potomac River and Susquehanna Flats,” said Bob Orth, scientist with the Virginia Institute of Marine Science and leader of the baywide annual survey. “However, the overall condition for bay grasses remains one of concern with many areas still having few, if any, grass beds.”
In the upper Bay (from the Susquehanna Flats to the Chesapeake Bay Bridge), bay grasses covered about 21,353 acres. This is a 10 percent decrease from 2009. Large increases were observed in the Chesapeake and Delaware Canal and part of the Sassafras River. However, these were offset by large decreases in local rivers, including the Bush, Bohemia and Magothy. The massive grass bed in the Susquehanna Flats continues to dominate this area.
In the middle Bay (from the Chesapeake Bay Bridge to the Potomac River and Pocomoke Sound), bay grass acreage decreased 11 percent to 35,446 acres. Most segments in this part of the Bay lost grasses. The largest percentage decreases occurred in the middle and lower central Bay, as well as the Choptank, Honga, Patuxent and Potomac rivers. Increases were seen in Tangier and Pocomoke sounds and the Manokin and Big Annemessex rivers, where eelgrass continued to come back following a 2005 die-off.
In the lower Bay (south of the Potomac River), scientists mapped 22,876 acres, a 1 percent increase from 2009. This is the fourth year that bay grasses in this part of the Bay have increased since 2005, when hot summer temperatures caused a dramatic large-scale eelgrass die-off. Most of the gains were in the upper Rappahannock, lower Piankatank, and the upper section and mouth of the James River. These gains offset losses in other areas.
“In 2010, our big concern arose in the lower Bay where eelgrass appeared to suffer another setback from the incredibly hot summertime temperatures,” said Orth. “Since we had mapped those beds prior to the heat wave, losses there are not reflected in our final figures. We believe the really hot summer temperatures in the early part of the growing season may have just cooked the grasses before we were able to map them, e.g. parts of the Honga River. The changes also occurred in areas dominated by just one species, widgeongrass, which has been shown to be a boom or bust species. 2010 may have been the hottest on record but it was those summer time temperatures in June that may have tipped the scale for SAV in some areas.”
Bay grasses – also known as submerged aquatic vegetation or SAV – are a critical part of the Bay ecosystem. They provide underwater life with food and habitat, absorb nutrients, trap sediments, reduce erosion, and add oxygen to the water.
Bay grasses are also an excellent measure of the Bay’s overall condition. The health of bay grasses is closely linked with Bay health. Annual bay grass acreage estimates are an indication of the Bay’s response to pollution control efforts.
Annual bay grass acreage is estimated through an aerial survey, which is conducted from late spring to early autumn. For more information about the aerial survey, and to view an interactive map of bay grass acreage throughout the Bay and its tidal rivers, visit VIMS’ website.
It takes a lot of work to protect the critical land that borders the Chesapeake Bay and its streams, rivers and wetlands. Mary Owens, conservation and education coordinator for the Maryland Critical Area Commission, takes us through a typical day in her job in our latest “From the Field” feature.
The calendar tells me that it is spring, and I am looking forward to a day in the field. As a natural resources planner for Maryland’s Critical Area Commission, my days are varied and involve a combination of tasks and activities that frequently have me outdoors. I love this part of my job!
The Critical Area Program is a natural resources protection and conservation program. Through the Critical Area Program, Maryland works cooperatively with local county and municipal governments to regulate land use and development activity within the state’s “Critical Area.” The Critical Area includes all land and water within 1,000 feet of tidal waters and tidal wetlands. Because of the Chesapeake Bay’s irregular shoreline, as well as the Atlantic coastal bays and all of the tidal rivers and creeks that feed into the bays, this “strip” of land includes about 680,000 acres -- about 11 percent of the state.
After stepping outside and realizing that the weather has turned back to a wintry chill, I get a fleece vest, scarf and gloves (just in case). In this line of work, you soon realize that it is always colder and windier near the water. While this is great in August, it can be a little rough in early April. It’s difficult to review a proposed development project or evaluate a forested buffer when all you can think about is being cold.
My first task for the day is to talk with my boss about a problem with a development project in southern Maryland. The project I am reviewing is an 11-lot subdivision that involves clearing a mature forest, which has been identified as Forest Interior Dwelling Species (FIDS) habitat. This type of habitat is very important to Maryland songbirds. Many songbird species have experienced significant population declines in the last several decades. The dwindling numbers are largely due to fragmentation of the large forested tracts (usually 50 to 100 acres) that songbirds need to nest and breed. To offset the impacts associated with clearing FIDS habitat, developers are usually required to plant and protect similar habitat on another property.
The problem is that a suitable FIDS mitigation site has not been identified for this project. So we have to notify the planning staff that the project cannot proceed without addressing this requirement. We agree to send a letter to the planning director to request a meeting to resolve this issue before any additional permits are issued.
My next activity is also related to FIDS mitigation, and it involves a FIDS Mitigation Bank that we have been working on for over a year. Over the last two years, Commission staff have worked very closely with several local governments and the Department of Natural Resources Wildlife and Heritage to develop FIDS Mitigation Banks throughout the Critical Area. This effort is essential to the successful protection and conservation of FIDS species.
I have just obtained updated survey information, aerial imagery and a forest management plan for a proposed bank. I meet with DNR Heritage staff to go over the information as we move toward “certifying the bank” as suitable for FIDS mitigation. The meeting goes well, and it looks like we have just over the necessary 100 acres that we hoped to protect on this property. Hopefully this “bank” will be “open for business” in the next month or so.
After these two meetings, I finally get on the road and head out to a site visit in Historic St. Mary’s City (HSMC). It’s rainy, windy, and cold, so I am glad I have extra clothes in the car. The purpose of my field trip is to meet with a horticulturist and other HSMC staff to explore the possibility of using goats to remove invasive plant species. Yes – goats! Low tech perhaps, but highly effective, since they eat undesirables like poison ivy and multiflora rose.
Within the Critical Area and particularly within the buffer (the first 100 feet adjacent to tidal waters, tidal wetlands and tributary streams), maintaining natural vegetation is very important. Unfortunately, this is the area where most people want to clear all of the vegetation so they can have a panoramic water view. Massive clearing, grading and bushogging are not allowed in the buffer because they remove natural forest vegetation, which is extremely important to water quality and habitat. These activities can also create severe erosion and sedimentation problems in tidal waters and wetlands.
Fortunately at Historic St. Mary’s City, they aren’t proposing to “clear” large buffer areas to create a view. Rather, they are looking at creative ways to address a serious invasive species problem. We walk around several areas of the property to look at the condition of the landscape and assess topography, soils, vegetation, and existing uses and access. In various areas, the invasive species have literally taken over the natural forest. Without eliminating these undesirable species, it is impossible for the buffer to function optimally. Often, removing invasive species and judiciously pruning trees can create a great view without compromising the value of the forested buffer. This type of work requires a Buffer Management Plan to ensure that the work is properly managed and that mitigation, in the form of supplemental planting, is provided if necessary.
The meeting with the owner of Eco-Goats goes well. It seems like using the goat herd may be a cost-effective and ecologically friendly method of addressing the invasive species problem. The owner tells us that the goats especially like many of the species that are present. The goats can also get to steeply sloping areas that are generally inaccessible to equipment and dangerous for humans. Using the goats is definitely preferable to applying herbicides, especially close to streams, wetlands and waterways. In the roughly one-half to 1 acre area that is identified as a good test site, he estimates that it would take 30 goats less than a week to munch the invasive species down to stems.
After this meeting, the HSMC staff wants to show me a site where they are proposing to construct a special events pavilion. The proposed location is outside the 100-foot buffer, which is good. Unfortunately, it is located in an area where there is an existing stormwater management facility, so that facility will need to be relocated. Fortunately, there are many new stormwater treatment technologies available, so it is likely that we well be able to use several smaller practices such as rain gardens, submerged gravel wetlands or infiltration practices. It’s really beneficial to have the opportunity to discuss various options at the beginning of the design stage, because planning is very important when you are proposing projects in the Critical Area.
My day wraps up in a good way as the sun finally comes out, and it feels like spring. I’ve driven quite a few miles, walked a couple of miles, and learned a lot about goats! As I head homeI drive past the St. Mary’s River, and the sun sparkling on the water is absolutely beautiful! It reminds me that it often does take many small efforts to accomplish things. Small steps, taken together, can eventually take you somewhere. It’s always good to not just focus on the destination, but to enjoy the journey as well.
The Chesapeake Bay’s blue crab population is at its second-highest level since 1997, according to results from the 2011 Blue Crab Winter Dredge Survey. At 460 million crabs, the blue crab population is nearly double the record low of 249 million in 2007.
Additionally, the survey shows that there are 254 million adult crabs in the Bay, a figure that is above the 200 million population target for the third year in a row. This marks the first time since the early 1990s that there have been three consecutive years where the adult population was above the target.
These figures indicate that emergency crab management measures put into place in 2008 are helping the Bay’s blue crabs recover, according to the Maryland Department of Natural Resources (DNR) and the Virginia Marine Resources Commission (VMRC).
“We continue to realize the benefits of the very tough decisions we made three years ago – decisions that are bringing us closer to our ultimate goal: a self-sustaining fishery that will support our industry and recreational fisheries over the long term,” said Maryland Gov. Martin O’Malley.
“The stock’s improved status from just a few short years ago is neither a random event nor a reflection of improved environmental conditions,” said Dr. Rom Lipcius, who directs the Virginia component of the dredge survey for the Virginia Institute of Marine Science (VIMS).
The unusually high crab abundance allowed watermen to harvest more than 89 million pounds of crabs, the largest amount since 1993. In addition, recreational crabbing license sales increased by 8 percent in 2010. However, the combined commercial and recreational blue crab harvest did not exceed the target of 46 percent. This shows that a healthy crab industry can coexist with stronger regulations, according to VMRC.
Despite these positive figures, overall crab abundance declined due to this past winter’s deep freeze that killed as many as 31 percent of Maryland’s adult crabs, compared to about 11 percent in 2010. Crab reproduction – which is heavily influenced by environmental conditions – was also lower in 2011.
“It was a harsh winter and crab mortality was higher than normal. In fact, it was the worst we’ve seen since 1996,” said VMRC Commissioner Steven G. Bowman. “Thankfully, we acted when we did in 2008 to begin rebuilding the crab population, or the crab census results we see today would be grim indeed.”
“The evidence indicates we’ve succeeded in rebuilding the stock to a degree that it can withstand a perfect storm of rapid temperature drop as crabs move into their overwintering grounds in the lower end of the Chesapeake Bay, followed by a prolonged bout of cold weather,” said VMRC Fisheries Chief Jack Travelstead.
Abundance estimates for young of the year, mature female and adult male crabs are developed separately. Together, these groups of crabs will support the 2011 fishery and produce the next generation of crabs.
The annual Blue Crab Winter Dredge Survey is the primary assessment of the Bay’s blue crab population. Since 1990, Maryland DNR and VIMS have sampled for blue crabs at 1,500 sites throughout the Chesapeake from December to March. By sampling during winter – when blue crabs “hibernate” by burying themselves in the mud – scientists can develop the most accurate estimate of the Bay’s blu crab population.
For more information about the blue crab survey results, view this presentation from Maryland DNR.
Maryland Gov. Martin O’Malley has signed an executive order to study septic system use in the state and find out how much pollution the on-site wastewater systems contribute to the Chesapeake Bay and its rivers.
The executive order forms a task force that includes representatives from science, business, government, agriculture and environmental advocacy communities.
The task force will review, study and make recommendations on a variety of septic and growth-related issues, including:
Approximately 411,000 Maryland households are currently on septic systems. During the next 25 years, new developments using septic systems are expected to account for 26 percent of growth in Maryland, but 76 percent of new nitrogen pollution. Maryland must reduce nitrogen pollution by 21 percent by 2020 to comply with the EPA's Bay pollution diet.”
"There's greater recognition now for the societal costs of sprawl development on septic,” said Governor O’Malley. “Continuing down the same path will undercut the progress we’ve made on restoring the health of the Chesapeake Bay and will overburden our farmers and other industries that are making changes to limit pollution in our waterways."
The task force will report its findings by December 1.
For more information about septic systems and pollution, view this presentation given by Gov. O’Malley to the Maryland General Assembly in March.