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Wetland Management in Cameroon

​​​​by Audrey Smylie 

The Illinois Natural History Survey, the University of Illinois-Urbana Champaign, the University of Bamenda, Cameroon and others collaborated to present a seminar on wetlands management in Cameroon attended by Wetlands Associate Audrey Smylie. The seminar presenter, Kongnso W. Edith, is a PhD fellow at the University of Bamenda, Cameroon and a researcher at the Ministry of Scientific Research and Innovation in Cameroon. 

Cameroon is located on the Gulf of Guinea at the intersection of western and central Africa. With a population of 25.5 million and over 475,442 square kilometers of land, it is comparable to the size of Texas. Wetlands in Cameroon, once referred to as “wasteland,” and were typically owned by the government and used by local people for cultivation or dumping. Once the Cameroon government recognized the social, economic, and environmental importance of wetlands, they began to look at management approaches and became a contracting party of the RAMSAR Convention (see 2/2/15 BPW blog on RAMSAR), which provides guidance on the use and conservation of wetlands. Contracting parties of the convention are committed to:

  • Working towards the wise use of all wetlands
  • Designating suitable wetlands for the list of Wetlands of International Importance (the “Ramsar List”) and ensuring their effective management.  (The Ramsar List includes the Chesapeake Bay)
  • Cooperating internationally on transboundary wetlands, shared wetland systems, and shared species​

This is an image of a map of Cameroon.
An image of tidal wetlands.

Cameroon’s seven RAMSAR sites comprise a total surface area of 827,060 hectares. Although they have been able to identify priority sites, Cameroon continues to face challenges in wetlands management, including:

  • Significant pressure to inappropriately exploit wetlands for economic gain resulting in wetland destruction or degradation  
  • The absence of decision-making processes for regulation of wetland activity (plans of action and implementation) 
  • Insufficient research
  • Invasive aquatic plants
  • Lack of agreement between stakeholders on regulatory approaches
  • Upland waste disposal sites

A case study of urban wetlands in the Yaoundé ​Sub-Division found 32% of the area covered by settlement (over 5,000 houses). Wetland health in Yaoundé is jeopardized by farmers’ heavy pesticide use, waste disposal, and dumping. 

Cameroon continues to explore solutions to their various problems in wetlands management. Focus points for the Central Government’s future of wetland management in Cameroon include: 

  • Stakeholder involvement from start to finish to ensure a participatory approach to management
  • Applicable laws and a strong institutional framework to ensure sustainable management
  • Use of remote-sensing and GIS as a time- and cost-effective management and monitoring strategy
  • The creation of wetland buffer zones to keep urbanization in check
  • Funding wetland research     




Municipal Lake, Yaoundé

A recording of the seminar can be found here . ​

Lagdo, Far North Region

Date: 9/21/2022 Category: News

Annapolis’ Living Wave Wall

​​by Audrey Smylie & Bill Morgante

Have you heard of a living wave wall? Many Maryland marinas incorporate wave attenuation structures or wave walls to reduce wave action since storm waves and boat wakes can harm boats and marina structures. Wave walls are typically made of nonliving materials, yet a wave wall with live oysters can be found in Annapolis! The Board of Public Works’ Wetlands Administration Associate and Wetlands Administrator recently visited Annapolis’ Eastport Yacht Club (EYC) to learn firsthand about their living wave wall.


Concrete “wave wall” shelves.

Located at the busy confluence of Spa Creek and the Severn River, EYC docks receive sizable swells from storms and boat traffic. Swells are a series of waves formed by wind blowing over a large area. With the help of dedicated volunteers and the Chesapeake Bay Foundation’s Oyster Restoration Center, the EYC designed a living wave wall to buffer swell and boat traffic. Under EYC docks, the wave wall is made up of concrete shelves (like a bookcase) that receive concrete triangles containing juvenile oysters called spat. In November 2011, EYC received a wetlands license from the Board of Public Works to authorize installation of their living wave wall. Once installed, the wall’s oyster triangles are inspected and replenished annually. Since oysters filter around 50 gallons of water per day, over the past 10 years water quality around EYC has benefited from wave wall oysters.

The annual maintenance of inspecting and adding oyster spat to the living wave wall at EYC commences each fall. EYC volunteers create triangular slabs using a special concrete recipe that provides the best conditions for oyster growth. Each slab is sent to the Chesapeake Bay Foundation Oyster Restoration Center to be impregnated with spat and then transported back to EYC. Next, volunteer divers suit up and first check the condition of the concrete triangles on each shelf. Oysters are measured, some aged oysters are removed, and some new triangles are installed. This effort is necessary to maintain the wall’s function, which mimics a three-dimensional oyster reef. For the installation of new triangles, paddle boards are used for transport to the divers.


Concrete triangle covered in juvenile oysters.

All in all, the annual maintenance of this living wave wall is a vigorous process, especially for the divers! We noted that EYC volunteers and divers alike share a love of water and environmental stewardship. To learn more about the living wave wall and to check out some underwater footage, visit​ . For other BPW Wetlands Web Blog posts on oysters, see blog posts from 8/15/18 and 5/17/17.

EYC volunteer diver with concrete triangles on a paddleboard.

EYC volunteer diver with concrete triangles on a paddleboard.

Date: 12/29/2021 Category: News

“Assumption” Provides an Opportunity for Maryland to Manage Waters and Nontidal Wetland Resources

by Bill Morgante. Gary Setzer, MDE Senior Advisor, contributed to this post

One way to expedite the licensing of nontidal wetlands projects in our State would be for Maryland to “assume” the administration of the federal Section 404 Clean Water Act1 program.

One way to expedite the licensing of nontidal wetlands projects in our State would be for Maryland to “assume” the administration of the federal Section 404 Clean Water Actprogram.

This topic – whether and how individual states can assume administration of Section 404 of the Clean Water Act from the federal government – was on the agenda at the recent Association of State Wetland Managers Annual Coordination Meeting in Leesburg, VA.  This gathering included 119 wetland managers whose mission is to protect wetlands in the 35 states (plus D.C.) they represent.

Through Section 404 of the Clean Water Act, the federal government regulates discharge of dredged or fill material into waters of the United States, including wetlands.  Part of that law allows states, in certain circumstances and with approval from the Environmental Protection Agency, to step into the federal role and administer the 404 program in navigable waters. 

Currently, New Jersey and Michigan are the only states authorized to assume Section 404 authority; Maryland and other states are presently evaluating the costs and benefits of assumption.

The Federal Section 404 Program

2.  Some farm activities are exempt.Section 404 regulated activities include fill for development and infrastructure expansion including roadways. Some farm activities are exempt.

Implementing Section 404 is assigned to the U.S. Army Corps of Engineers (Corps) which must issue a permit before a project may discharge dredged or fill material into regulated waters and wetlands.  Discharge of dredged or fill material will not be permitted if: (1) a practicable alternative exists that is less damaging to the aquatic environment; or (2) wetlands and waters would be significantly degraded.  

Water Quality Certification is a prerequisite to a federal Section 404 permit. Under the 404 Program3, a state must certify that activities discharging dredged or fill materials into state waters will not violate the state’s water quality standards adopted to protect aquatic life, drinking water, and recreation.

An applicant for a permit must demonstrate steps taken to avoid impacts to wetlands and to minimize impacts that cannot be avoided. For unavoidable impacts, the permittee may have to provide compensation

The magnitude of the proposed impacts determines the extent of the Corps’ review:

  • Minimally adverse impacts usually require a General Permit. This permit process is less onerous for the applicant than an Individual Permit review (see below) and allows certain activities to proceed with little or no delay.  Example: minor road activities and utility line backfilling.
  • Potentially significant impacts require an Individual Permit. The Corps evaluates these applications under a public interest review, as well as the environmental criteria set forth in the Section 404(b)(1) Guidelines.

Maryland and Assumption

The preamble to the Maryland Nontidal Wetlands Protection Act states: “That it is the State’s intention to evaluate the feasibility of assuming the permit program under Section 404 of the Clean Water Act after implementation of a statewide permit program for nontidal wetlands4.”   The Act was adopted in 1989 and Maryland’s Statewide nontidal wetlands program began in January 1991. 

State officials met with EPA officials in 1993 to review Maryland’s statutes and regulations and assess their consistency with the Clean Water Act. Differences identified at that time demonstrated that the General Assembly would have to make law changes before Maryland could assume Section 404 authority.  Legislation to align Maryland’s statutes with the Clean Water Act as a prelude to developing a State application for assumption, however, failed in the 1994 and 1995 General Assembly sessions5. 

Nearly 25 years later, Maryland is again investigating the benefits and costs associated with assuming the Section 404 program.  The Initial Report of Governor Hogan’s Regulatory Reform Commission (2015) recommended: “The State should pursue transfer of jurisdiction from the Army Corps of Engineers to the Maryland Department of the Environment.  This will eliminate a huge time delay and will remove a possible third level of review for permits and applications.”  The MDE has reopened its dialogue with EPA to determine the statutory changes that will be necessary to align Maryland’s nontidal wetlands and waterways statutes with Section 404 of the Clean Water Act.

NOTE: The Clean Water Act requires the federal government to retain permitting jurisdiction over “all waters which are subject to the ebb and flow of the tide shoreward to their mean high water mark . . . including wetlands adjacent thereto6.”   As a result, it is unlikely that the Board of Public Works issuance of State tidal wetlands license would be affected if Maryland assumed the 404 Program since it is targeted toward nontidal wetlands.

1 33 USC § 1344

2 Maryland Nontidal wetlands Protection Act, ch. 536, 1989 MD Laws 3301, 3302 (uncodified language)

1994 General Assembly: House Bill 414/Senate Bill 291 offered amendments to Title 8 of the Natural Resources Article, Subtitles 8 and 12, identified by EPA as necessary for the State to assume Section 404 authority.

1995 General Assembly: House Bill 820/Senate Bill 649 offered amendments to Title 8 of the Natural Resources Article, Subtitles 8 and 12, to improve consistency between the State and federal nontidal wetlands programs.

6 33 USC § 1344(g)(1)

Date: 7/11/2019 Category: News

Study of Living Shoreline Projects Licensed by the MD Board of Public Works between 2013 & 2018

More than ten years ago, State Tidal Wetlands Law was amended by the Living Shoreline Protection Act of 20081 to mandate that “improvements to a person’s property against erosion shall​ consist of Living Shorelines2 unless an exception is granted authorizing structural measures3.”  The preference for using a Living Shoreline approach to stabilize shoreli​nes against erosion derived from growing concerns that climate change is connected to sea level rise leading to increased shoreline erosion, and that shoreline protection using Living Shorelines is optimal because they “trap sediment, filter pollution, and provide important aquatic and terrestrial habitat4.”

In the decade that followed, the Board of Public Works has issued State Tidal Wetlands licenses for numerous Living Shoreline projects in Maryland’s tidal waters5.  Based on this body of experience of BPW-licensed Living Shoreline projects, now is an appropriate time to evaluate the success of the Living Shoreline approach.

Specifically, Wetlands Administration evaluated 16 Living Shoreline projects that were licensed in the past five years to:

  • Evaluate success for these 16 living shoreline projects.
  • Inform the Board of Public Works about whether the intent of the 2008 amendment has been fulfilled.
  • Encourage the creation of a Living Shoreline database in Maryland usable by living shoreline designers, property owners with living shorelines, and property owners considering this approach.

Success of Living Shoreline Projects Summary

Of 16 Living Shoreline projects evaluated, 15 are successful. This study focused on three specific criteria assessed based on site visits to each site without detailed scientific study.
The three criteria include the project’s ability to: stem erosion, establish native vegetative cover of 85%, and have low incidence of invasive plants6.

  • Stemming erosion: Fifteen of 16 sites eliminated or substantially stemmed erosion through the installation of stone sills or breakwaters7.
  • Vegetative cover: Fifteen of 16 sites had at least 85% vegetative cover, meaning that a viable native plant community is established. This threshold is a marker for success8 in wetland mitigation projects.
  • Invasive plants incidence: While thirteen of 16 sites had the invasive Phragmites species present, it was present in low levels. These projects will require monitoring and annual herbicide application to eradicate Phragmites.

Success of these three baseline criteria can be used to infer that overall living shoreline projects are providing additional ecosystem services as well9.

Study Methods

The Wetlands Administrator and the Wetlands Associate visited 16 Living Shoreline projects in the summer and fall of 2017 and 2018. Though State tidal wetland licenses authorize the State to access project sites, for the purposes of this study each licensee was contacted to obtain permission for the Wetlands Administration’s site visit. As a result, most site visits included a project designer or the licensees themselves who were enthusiastic about discussing their project.

Three criteria were used to evaluate the success of Living Shoreline projects:

  1. Has the project halted erosion? Has living shoreline design remained intact, been undermined by erosion, or been destroyed?
  2. Does the project have 85% vegetative cover? Living shoreline projects with 85% or greater cover with native plants are considered successful.
  3. What is the incidence of invasive plant cover? Little or no invasive plant cover is required by Maryland Department of the Environment (MDE) licenses and U.S. Army Corps of Engineers (USACE) permits for newly-established living shoreline projects. If invasive plants are present, a plan to remedy the problem is required.

Wetlands Administration created a form to record project information at each site. Findings concerning the three criteria, project size, current condition, and other additional benefits were tabulated10. Specifically, field observations were recorded for the presence of invasive plant species, sill height11, degree of erosion, and additional observable benefits. Photos were also taken at each site12.

Study Results: 15 of 16 Living Shoreline Projects Deemed Successful

Fifteen of the 16 Living Shoreline projects – or 94% – are successful. The Summary Table details the characteristics found at each site. Overall:

  • Fourteen projects had no erosion; one had some erosion; the one unsuccessful project had severe erosion.
  • Fifteen projects had 85% or greater vegetative cover with native plants. Only one project – the project showing severe erosion – had less than 85% vegetative cover.
  • Six projects had no invasive plants; eight projects had up to 5% Phragmites; two projects had up to 15% Phragmites. Three of the ten projects with Phragmites have plans for herbicide treatment to eradicate it.
    NOTE: Phragmites australis was the only invasive plant noted during this study.

The 14 projects with no erosion are, according to the above criteria, successful. The one project with some erosion is also a success as it is characterized by more than 85% native-plant cover and contains no Phragmites.

Although ten projects had some Phragmites, the small concentration of invasive plants does not offset those projects’ success in stemming erosion and providing abundant native plants.

The Wetlands Administration concludes that the results of Living Shoreline projects affirm Maryland’s decision a decade ago to adopt a preference for the Living Shoreline method of shore erosion control in response to climate change and sea level rise. The following table and photo log provide field data collected for these projects.


1 Chapter 304, 2008 MD Laws​.

2 A Living Shoreline is a “nonstructural stabilization method” that uses plants, sand, rock, or other natural materials to protect against erosion and to create, maintain, or enhance wildlife habitat.

3 § 16-201(c), ENVIRONMENT Article, Annotated Code of MD. Examples of structural measures include riprap, retaining walls, and bulkheads.

4 See Preamble, Chapter 304, 2008 MD Laws:

  • The State and its people, property, natural resources, and public investments will be significantly impacted by climate change and sea level rise
  • Sea level rise contributes to the erosion of approximately 580 acres of Maryland shoreline annually
  • The Maryland Commission on Climate Change recommends the State begin to actively address the impacts on the natural environment of shore erosion induced by sea level rise
  • State public policy is to protect natural habitat
  • Living Shorelines are the preferred method of shore protection.

5 The BPW issues all State tidal wetlands licenses pursuant to § 16-202, ENVIRONMENT Article.

6 MDE permit and license requirement and USACE permit requirement.

7 Stone sills and breakwaters are stone barriers located along the shoreline that absorb wave energy and dissipate erosion.

8 USACE and MDE marsh mitigation projects required a minimum 85% vegetative cover to be deemed successful

9 Additional ecosystem services can include wildlife habitat, aesthetics/cultural heritage values, recreation, aquifer recharge, flood storage, carbon storage, water quality improvement, and education.

10 See Summary Table.

11 Sill height is a measurement of interest to designers and was not a criterion for success.

12 See Photo Logs 1-3.

Date: 3/13/2019 Category: News

Some Chesapeake Bay Natural History, featuring the Bay Oyster!

by Bill Morgante.  Ethan Glaudemans, UMD Class of 2019, contributed reporting & research

[Note: Many news stories have appeared recently concerning heavy trash and sediment loads in the Bay resulting from frequent storms and water releases from the Conowingo Dam. Though this blog was prepared prior to these storms, the relevance of an oyster’s ability to improve water quality (as is discussed below) is all the more relevant.] 

Around 35 million years ago life was humming along in the Chesapeake Bay when BAM, a meteor struck in the area of Cape Charles, VA. This one to three mile wide meteor exploded in its descent through the atmosphere before crashing down. Within seconds a depression 17 miles across was created. The depression formed a basin that gradually expanded to 56 miles across, as the water inside repeatedly froze and thawed – creating the Chesapeake Bay. (USGS Fact Sheet 049-98)

Fast forward 34+ million years. As global sea levels rose, the Chesapeake’s rivers and channels were carved out. Coastal wetlands and hardwood forests characterized the Bay area 11,000 years ago when Native Americans began to colonize the area. The oyster, an important component of the Bay’s ecology today, began to colonize local waters alongside fish around 5,000 years ago. (The Oyster in Chesapeake History, Dr. Henry Miller)

When in 1608 Englishman John Smith departed Jamestown, VA the first English colony in the States, to explore the Chesapeake Bay, he described the Bay as a place “heaven and earth seemed never to have agreed better to frame a piece for man’s commodious and delightful habitation.” Smith, of course, was not the first to stumble across the 4,400 square mile Bay — many Native Americans had already populated its margins. The name Chesapeake translates from the Native American language to mean “mother of waters” or “great shellfish bay.” Later the area around the Bay became populated with settlers who took advantage of its waters bursting with oysters. As the local population grew, so did the popularity of the oyster – oyster harvests peaked in the late 1800’s. (The Oyster in Chesapeake History, Dr. Henry Miller)

  • 1608 — John Smith wrote oysters lay as “thick as stones”
  • 1880’s – 17,000,000+ oyster bushels/year harvested
  • 2016 — 400,000 oyster bushels/year harvested.

One constant in the Chesapeake Bay over the last 100+ years – oysters are important. While in the past they were loved both by watermen harvesting them and consumers relishing their salty taste, today we have an additional reason to love them. They help us clean the Bay!

In 2016, the Bay watershed was home to 18.1 million people – 6.08 million in Maryland. Development pressure on the Bay watershed is enormous — we love living, fishing, recreating, and farming near the Bay and we consequently compromise its water quality. The three major contributors to the poor water quality of our streams, rivers, and the Bay – nitrogen, phosphorus, and sediment are a tough pollution mix to combat. The 83,000 farms located in the Bay watershed (8/9/18 Bay Journal) contribute nitrogen pollution to the Bay (45% according to the CBF website), yet air pollution, stormwater runoff, and wastewater treatment are also major contributors. Since most of us are part of creating the waste stream for the latter three items – our daily habits can help curb pollution from these three!

Oysters help clean up Bay waters since they are filter feeders. They pump water through their gills, trapping particles of food as well as nutrients, suspended sediments and chemical contaminants (Chesapeake Bay Program). Whether you personally like eating oysters or not, they filter more than 50 gallons of water in a single day!  Next time you enjoy an oyster with a dash of horseradish, appreciate the job they are doing to help clean up the Bay!


Date: 8/15/2018 Category: News

Wetland Types in Maryland

by Bill Morgante.  Kristin Webb, UMD Class of 2018, contributed reporting & research



Doesn’t the marsh above located in North Beach, Calvert County look like a scene from a pretty picture book? This marsh is only one of many wetland types in Maryland. Marsh is considered an estuarine type of wetland, while other Maryland wetland types include palustrine, riverine and lacustrine.

Doesn’t the marsh above located in North Beach, Calvert County look like a scene from a pretty picture book? This marsh is only one of many wetland types in Maryland. Marsh is considered an estuarine type of wetland, while other Maryland wetland types include palustrine, riverine and lacustrine.


Hydrogeomorphic (HGM) System, which is used to categorize wetlands primarily by their functions.1 
The other, the Cowardin System, is a taxonomical approach that inventories Maryland wetlands into estuarine, palustrine, riverine, and lacustrine categories.2, 3 I’ll use the latter approach to reference wetland types in Maryland.

There are several classification systems used to identify wetlands, however in the United States there are two systems uniformly recognized. One is the, which is used to categorize wetlands primarily by their functions.The other, the, is a taxonomical approach that inventories Maryland wetlands into estuarine, palustrine, riverine, and lacustrine categories.I’ll use the latter approach to reference wetland types in Maryland.

Image: Jug Bay Wetlands Sanctuary, Lothian, Anne Arundel County

Image: Jug Bay Wetlands Sanctuary, Lothian, Anne Arundel County


In an earlier blog post, “Maryland Salt Marshes: Workhorse Ecosystems Worthy of Respect” the most familiar type of estuarine wetland in Maryland – the tidal salt marsh was discussed. In estuarine wetlands, where salt content is greater than 18 parts per thousand, expect to smell sulfur gas released by wetland soils. In Maryland, estuarine wetlands are found along the Atlantic and Bay coastlines, and in the higher salinity portions of Bay rivers.


Palustrine wetlands are considered freshwater wetlands though some are subject to tidal fluctuation and their salt content is less than 5 parts per thousand. Salt from the ocean is filtered out of the water through a combination of plants and soils, creating a completely different ecosystem from the tidal salt marshes. Soil gases contain methane, resembling the smell of a cow field. Plant species diversity increases dramatically in palustrine wetlands since the stressor of high salinity is removed. In Maryland, palustrine wetlands include both swamps and tidal freshwater marshes. An earlier blog post mentioned Battle Creek Cypress Swamp (below), a beautiful local example of a palustrine wetland.




Riverine wetlands can be found along freshwater rivers and streams with green blankets of aquatic vegetation, emergent (herbaceous) wetlands, scrub-shrub wetlands or forested wetlands. The Patuxent River trail (below) is an example of this type of ecosystem.




Lake Artemesia in College Park (below) with its abundant lily pads and cattails is a freshwater lacustrine wetland ecosystem, consisting primarily of non-tidal marshes. Lily pads and cattail mark the boundaries of these lacustrine marshes and make up the common vegetation type for  many lakes and ponds in Maryland.




1 Brooks, R. P., Brinson, M. M., Havens, K. J., Hershner, C. S., Rheinhardt, R. D., Wardrop, D. H., & Rubbo, J. M. (2011). Proposed hydrogeomorphic classification for wetlands of the Mid-Atlantic region, USA. Wetlands, 31(2), 207-219.

Brooks, R. P., Brinson, M. M., Havens, K. J., Hershner, C. S., Rheinhardt, R. D., Wardrop, D. H., & Rubbo, J. M. (2011). Proposed hydrogeomorphic classification for wetlands of the Mid-Atlantic region, USA. Wetlands, 31(2), 207-219.

2 Cowardin, L. M. (1979). Classification of wetlands & deepwater habitats of the US. Diane Publishing.

Cowardin, L. M. (1979). Classification of wetlands & deepwater habitats of the US. Diane Publishing.

3 Tiner, R. W. (2016). Wetland Indicators: A Guide to Wetland Formation, Identification, Delineation, Classification, and Mapping. Crc Press.

Tiner, R. W. (2016). Wetland Indicators: A Guide to Wetland Formation, Identification, Delineation, Classification, and Mapping. Crc Press.


Date: 6/1/2018 Category: News

Tell Me About Wetland Ecosystem Services!

by Bill Morgante. Ethan Glaudemans contributed reporting & research

Historically “swamps” were synonymous with dark, murky forests, lurking crocodiles in algae-filled water, and maybe even a lonely ogre. While the layperson’s appreciation today for wetlands has increased, it is still the case that the breadth of services that swamps and other wetlands provide is greatly underestimated. Collectively the many valuable services that wetlands provide are termed “wetland ecosystem services.” Let’s examine these services.

  • Biological diversity:  wetlands provide habitat for many trees, plants, birds, fish, amphibians, crustaceans, and insects – more than a third of U. S. threatened and endangered species live in wetlands!

  • Aquifer recharge: wetlands hold large amounts of standing water that slowly leaches into the ground. This recharges aquifers – large areas of saturated soil that provide drinking water for over 115 million Americans.

  • Water quality improvement: when waters flow through wetlands, a wetland’s plants and soils together with wetland chemical processes filter pollutants thereby enhancing water quality. 

  • Storm abatement, flood storage, and flood mitigation:  wetlands are exceptionally useful at slowing and absorbing water, serving as an important component in flood protection. In many cases, when it comes to flood protection, wetlands can be more economical and stronger than floodwalls and levies.

  • Carbon sequestration: all types of wetlands are carbon sequestering systems (aka “carbon sinks”). That means wetlands have the ability to store excess carbon (via photosynthesis) from the atmosphere – one of the primary components of greenhouse gases and a driver of climate change.  Drainage and degradation of wetlands can release significant amounts of this stored carbon back into the atmosphere in the form of methane and reduce the ability of wetlands to sequester additional carbon. Better management practices can help protect these stores of carbon and the ability of wetlands to sequester it. (ASWM, 2018) See 6/15/15 blog on Blue carbon, the type of carbon stored by coastal wetland vegetation.

  • Nitrogen cycling: chemical processes in wetlands soils allow N2 gas to be returned to our atmosphere (made up of 78% N2) whereas most upland soils pull nitrogen from the atmosphere but cannot return it.

  • Aesthetic, cultural, and provisioning: the beauty of many wetlands inspires art, wetlands provide a home and livelihood for many cultures, and when wisely managed can provide us with plentiful and varied seafood options. As mentioned in the previous Migration blog, most avian migration flyways use wetlands for feeding or as a final destination.

  • Recreation:  many tourists enjoy recreating in wetlands to fish, swim, bird-watch, kayak, and canoe. During 2016, there were 35.8 million total anglers in the United States, accounting for a total fishing expenditure of $46.1 billion (USFWS, 2016).  Many sport and commercial fish species depend on wetlands for all or part of their life cycles. Birding is currently enjoyed by more than 45 million Americans (USFWS, 2016). Wetlands are also a prime destination for all types of recreational boaters. Ecotourism has recently gained world-wide popularity.

  • Education:  wetlands are complex habitats that give people the opportunity to ask questions about their formation, services they provide, and organisms they house.

Healthy wetlands are a self-sustaining ecosystem providing a wealth of wetland ecosystem services for animals and humans alike. These habitats serve as a bridge between terrestrial and aquatic environments and help maintain processes in each, creating a net benefit that should not be underestimated.

Date: 3/16/2018 Category: News

Maryland’s Wetlands: An Essential Link to Eastern Seaboard Bird Migration

by Bill Morgante. Ethan Glaudemans contributed reporting & research

Maryland winters with their chilling temperatures, snowy and icy grounds, and barren landscapes are the catalyst for many local birds and more than 350 species throughout North America to migrate to the warmer, more bountiful equator. As winter days grow shorter and colder the “bird brain” changes causing avian restlessness and increased appetites in preparation for migration. Some birds actually double their body weight during this period! Next, birds form flocks and migrate to winter destinations using the sun and stars, natural landmarks, and the earth’s magnetic field.

Maryland winters with their chilling temperatures, snowy and icy grounds, and barren landscapes are the catalyst for many local birds and more than 350 species throughout North America to migrate to the warmer, more bountiful equator. As winter days grow shorter and colder the “bird brain” changes causing avian restlessness and increased appetites in preparation for migration. Some birds actually double their body weight during this period! Next, birds form flocks and migrate to winter destinations using the sun and stars, natural landmarks, and the earth’s magnetic field.

Many of Maryland’s locals take south for the winter, with species like the osprey, Baltimore oriole, and great blue heron vacating the state in exchange for warmer climates. For some northern birds, Maryland is their southern migration destination, with species like tundra swans, Canada geese, and dabbling ducks making Maryland their winter home. This past December I enjoyed the unique sounds of tundra swans ( click here!​ ) at my favorite local park on the Magothy River.

The Chesapeake Bay serves on the wing as an active migration flyway and on the ground as a food source with abundant wetlands serving as a rest stop for migrating birds. Since wetlands are important bird habitat for food, shelter, water, and nesting, it’s no surprise that the Chesapeake Bay is a hot travel destination during migration as an avian “rest stop” or to hunker down until spring. The Bay is migratory home to roughly 1,000,000 waterfowl during winter, roughly one third of all waterfowl wintering along the Atlantic. The tundra swans I spotted on the Magothy River, feed on Bay submerged aquatic vegetation such as redhead grass, widgeon grass, and sago pondweed.

Most admire the wonder of this annual bird migration, yet it’s worth mentioning that humans have caused some migration impediments. Birds sometimes collide with urban skyscrapers, particularly those with reflective windows, and anthropogenic magnetic fields and light pollution at night beckon birds to stray from their usual paths. The warmth of cities entice species like the Canada goose to become permanent residents, causing disruption to urban ecology with large goose populations polluting waters with goose poop …and causing a mess!

While it’s important to protect and restore Maryland’s wetlands for the many services they provide (more about this in next month’s blog), these wetlands also serve an important role in bird migration. Many Americans enjoy watching birds during migration… and throughout the year. The 45 million American bird watchers contribute over $75 billion a year to the U.S. economy. So by investing time and money towards wetland protection and restoration, we are protecting wetlands’ avian inhabitants… and investing in a stronger economy.

Note: February 2nd is World Wetlands Day! Check here for February 2, 2015 post on the significance of World Wetlands Day

Date: 2/1/2018 Category: News

Maryland Oysters – Past Wars & Present Challenges

An important chapter of Maryland history with relevance today is the Oyster Wars saga beginning around 1830 and featuring oyster pirates, boat chases, gun fights, and cannons. Through the nineteenth century, skirmishes pitting pirates against enforcement officers, and tongers against dredgers occurred fairly often and even resulted in fatalities. Today, having moved beyond the fierce Oyster Wars, watermen, environmental scientists, elected representatives, and Marylanders, still retain their deeply-held, and often conflicting, opinions about harvesting and restoring Bay oysters. Current trends are hopeful for the future of Maryland oysters. 


Wars over oysters began early in the 1800s when upon the apparent depletion of New England oysters, the Chesapeake Bay was found to have a plentiful stock. So plentiful in fact that oyster harvesting reached its peak in the mid-1880s when more than 17 million bushels were taken from the Bay annually. Battles over the local Bay oysters were both violent and political.

The Oyster Wars are memorialized in the records of the Board of Public Works:

A petition of the citizens of the eighth district of Anne Arundel County, asking that they be furnished with a cannon to protect oyster grounds from depredation, was presented to the Board and ordered to be filed.  The Board decided that they have no authority for such proceedings –besides they have no cannon. 


The 1865 Maryland General Assembly, hoping to protect Maryland watermen against oyster seekers arriving from Virginia and New England, restricted oyster catches in State waters and required anyone harvesting or selling oysters to obtain a license from the Comptroller – but only Maryland residents could be licensed.  By 1874 the Maryland Oyster Navy operated nine vessels outfitted with cannons that cruised State waters, verifying that those catching, buying, or selling oysters be licensed, and violators would be arrested. 

The final Oyster Wars skirmish took place on the Potomac near Colonial Beach in 1959. An oyster dredger from Virginia saw a police boat and sped toward the Virginia shoreline; Maryland police pursued his boat, firing a warning shot, which killed him. His death proved to be the last of the bloody conflicts as the states entered into the Potomac River Fisheries Compact.



Today oysters are still in great demand – highly valued for both their environmental contributions (cleaning the Bay water they inhabit and producing live bottom) and for harvesting (from the Bay to your dinner plate).  These facts will provide context for analyzing oyster harvest and restoration issues.


Oyster Science

1. Maryland’s current oyster population is at record low levels compared to historic levels. Based on harvest records oysters have declined to less than 2% of historical harvest levels. 

​# of Bushe​ls Harvested
​Oysters “lay as thick as stones.” -John Smith​
​17,000,000 (est.)
​3,000,000 (est.)

2. The decline in the oyster population is a result of disease, harvesting, and changes in water quality. Silt and sediment deposits on oysters cover vital shell habitat and deter the setting of new oysters (called spat) to the bottom. Improving water quality to reduce the deposits is critical to supporting a vibrant oyster resource.


3. Oysters clean the Bay and its tributaries – an average oyster is able to filter up to 30 gallons of water a day.  

4. An oyster bar has firm shell bottom built up over centuries from generations of oysters inhabiting an area. A bar is a two-dimensional structure with a typically low oyster population and varying numbers of oysters depending on spat setting rates. 

4. An oyster reef is a dense population of oysters that creates a three-dimensional structure on the Bay bottom. Because a reef contains many oysters, they attract many other organisms and create a diverse ecosystem. A reef can develop in as few as 3 to 5 years as a result of a strong natural spat set or a dense planting of hatchery seed. Reefs and well-populated bars provide habitat for crabs, clams and finfish, as well as promoting oxygen mixing to offset dead zones.  

5. Dead zones and disease: Dead zones are areas where oxygen is not sufficient to support marine life. Low oxygen levels – due to nitrogen and phosphorus pollution – have been shown in the laboratory to weaken an oyster’s immune system and increase oyster susceptibility to oyster diseases, like Dermo and MSX.


 Dead zones may not be a problem for Bay oysters since most oyster bars are shallower than a typical dead zone location. ​

Maryland Department of Natural Resources (DNR)

1. DNR is responsible for conservation management of fisheries, fish resources, and aquatic life in Maryland


, including oyster harvesting and restoration.

2. DNR’s Oyster Advisory Commission, established in 2007 and restructured in 2016, is charged with advising DNR on Bay oyster issues – specifically, strategies for “rebuilding and managing the oyster population.”


 Currently, the Commission is a 23-member group composed of watermen, scientists, lawmakers, and environmentalists. 

3. DNR manages oyster harvesting and the oyster population through two management types: Harvest Areas and Sanctuaries Areas.

• Harvest Areas are those areas where oyster harvesting is legal. They are managed by season, daily limits, a size limit on oysters to conserve oyster broodstock, and other laws. Some harvest areas are planted with hatchery produced seed oysters to boost harvest levels.

• Sanctuary Areas are State-designated and marked areas that prohibit the harvest of oysters. Of 51 sanctuaries in Maryland, three have large scale oyster restoration projects underway, with two more in the selection phase. Most sanctuaries have only limited amounts of restoration efforts underway due to lack of funding. 

• Maryland established the first oyster sanctuaries in the 1960s and expanded them in the 1990s, with a more recent and significant expansion occurring in 2010.

• The sanctuaries are specifically established to: 

-Protect the most productive oyster grounds

-Provide ecological functions not obtained on harvested oyster bars 

-Serve as reservoirs of reproduction generating larvae to populate other  areas including public shell fish areas

-Facilitate development of natural oyster disease resistance 

-Increase the ability to protect against poaching 

4. In 2010, DNR designated the sanctuary areas that exist today.


  The 51 sanctuaries cover approximately 9,000 acres or about 24% of the Bay’s estimated remaining oyster bar habitat. 

Three-quarters of the Bay’s oyster reefs were removed between the Civil War and the 1920s,
leaving huge mounds of shells like this. Photo credit: CBF

Today’s Challenges

1. Water quality: Efforts to control nitrogen and phosphorus pollution are critical to support successful oyster establishment.


2. Lack of hard Bay bottom and oyster shell.

• Young oysters grow by attaching themselves to older oysters or to other hard surfaces. 

• Siltation and historical harvesting have buried or stripped away older oyster shell and other hard surfaces. Nearly 70% of oyster reef habitat along the Bay bottom and its tributaries has been lost to siltation. 

• Successful demonstration projects have shown how to successfully build oyster reefs with old shell, concrete, and construction rubble, and then plant these structures with oyster spat. 

3. Poaching: DNR engages in continual efforts to combat illegal oyster harvesting (poaching) which remains a problem.



1. The Oyster Advisory Commission is currently evaluating potential changes to the sanctuary program. These changes include plantings for sanctuaries, modifying boundaries (reducing some/expanding some), creating rotational harvest zones that will limit and rotate harvest to provide for harvest and ecological value, and selecting two additional tributaries for large scale restoration that will bring Maryland’s commitment up to five restoration tributaries. 

2. Legislation from the 2017 General Assembly 


  prevents DNR from reducing or altering the current oyster sanctuaries boundaries until a management plan is developed following completion of DNR’s final report to the Governor and Oyster Advisory Commission on its stock assessment study in December 2018.  

3. An increasing number of watermen are obtaining leases and adding oyster farming as an additional income source while continuing their work in public fishing grounds. 



Oyster Wars of the Chesapeake Bay, Susan Elnicki Wade

Oyster Wars of the Chesapeake Bay, Susan Elnicki Wade

2 Board of Public Works Minutes (Jan. 20, 1887) quoted in The Maryland Board of Public Works: A History,
Alan Wilner, at 66-68 (1984).

3 Potomac River Fisheries Commission,

Potomac River Fisheries Commission, MD Manual

4  2004 Chesapeake Bay Oyster Management Plan. P. 1


On the Brink: Chesapeake’s Native Oysters: What it Will Take to Bring Them Back,
CBF (July 2010); pg. 5


Section 4-202, Natural Resources Article, Annotated Code of Maryland.


Section 4-204, Natural Resources Article, Annotated Code of Maryland.

8 On the Brink: Chesapeake’s Native Oysters: What it Will Take to Bring Them Back,
CBF (July 2010); pp. 11-12

9 U.S. Army Corp of Engineers Environmental Assessment (2009).

10 Oyster Poaching Continues on Bay Despite Enforcement Efforts , Baltimore Sun (4/4/2015)11 Laws of 2017, ch. 27​


Date: 5/17/2017 Category: News

World Wetlands Day – Feb 2, 2017


Date: 2/2/2017 Category: News

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