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The Summer Gooses…Clay Banks…Hodge’s Bar…The Triangle…Stone Rock… Just a sample of the many famed fishing spots throughout Maryland’s Chesapeake Bay noted for the distinct attributes of their benthic profile or bathymetry — their bottom contour or underwater landscape. All of these locations are known to anglers as excellent places to fish because a variety of species have an affinity for the habitat in those areas.

Unfortunately as time has passed, some of these locations have suffered from significant sediment deposition, loss of shell bottom, or other detrimental impacts.

To offset the loss of productive habitat, fishery managers have experimented with the use of alternate materials. Aquatic artificial reef development is man’s effort to enhance fish habitat and improve sportfishing opportunities where habitat is compromised or does not support fish populations.

photo of a sinking decommissioned shipLooking Back
The history of artificial reefs in Maryland dates back several decades, with anecdotal information suggesting that these efforts were undertaken as far back as the early 1900s — and perhaps even earlier. Documented records began some 40 years ago in the mid-1960s, when permits were first required. Manmade efforts to improve fish habitat have been conducted in Maryland’s streams, rivers, lakes, ponds, the Chesapeake Bay and the Atlantic Ocean. Materials used have included trees, brush, rock, concrete, tires, steel, cable and obsolete vessels.

The general principal upon which aquatic artificial reefs are based involves providing both predatory and baitfish with a refuge, source of food, or both, in areas where they previously were not abundant or did not exist. Reefs can be benthic, suspended in mid-water, or on the surface. Efforts have included many different approaches in a variety of habitats.

An example of reef development in inland waters can be found in Liberty Reservoir, a nontidal drinking water supply reservoir just west of Baltimore City in Baltimore County. Liberty Reservoir is a steep-sided, clear impoundment relatively devoid of structure. Because of this, it was considered a prime candidate for fish habitat enhancement through creation of artificial reefs.

photo of several modules specifically designed for reef habitat stacked on a bargeDuring the mid-80s, a variety of aquatic reefs were constructed and placed into the Reservoir. They included benthic reefs composed of concrete pipe for species such as channel catfish; brush piles for schooling fish such as yellow perch, crappie and sunfish; and suspended structures using black locust (an extremely durable and locally plentiful hardwood) attached to wire cables at various depths for large predators such as striped bass. The latter drew clouds of baitfish to the sanctuary of suspended locust branches. In turn, the concentrated availability of baitfish attracted large striped bass to the structure.

In the Chesapeake Bay, numerous aquatic reefs have been built over the years and today 21 reef sites are currently permitted for materials by the U.S. Army Corp of Engineers (ACE).

From simple concrete rubble, to elaborate suspended fish aggregating devices — devices suspended in the water column to attract more highly mobile species — a multitude of approaches have been tried in an effort to improve sportfishing opportunities. In 1986, a modular maze of fiberglass and steel assembled using Japanese technology was deployed at the Cedar Point Reef at the mouth of the Patuxent River.

In the waters of the Atlantic off Ocean City and Assateague Island, there are a number of artificial reef sites. Some are in shallow water just a few miles off the beach, such as the Bass Grounds and Great Gull Reef. Others are further offshore, in waters over 100 feet deep, including the Twin Wrecks Reef and the Great Eastern Reef.

Materials used in the Atlantic tend to be an order of magnitude larger, including miles of obsolete communications cable, large scuttled vessels and even tanks or other military equipment. Just as in the Chesapeake, these sites have been permitted and under development for many years, some dating back to the 1960s.

photo of workers on barge lowering concrete pipe segments into the waterMixed Results
Efforts in inland waters have been most successful when implemented on a smaller, simpler scale. Christmas trees wired together and placed into smaller lakes and ponds have yielded a quick response in attracting fish, whereas other labor intensive experiences may be largely unsuccessful. The Liberty Reservoir project required a great deal of manpower and time, yet the materials placed attracted only a modest number of fish and feedback from recreational anglers was lukewarm in terms of their success.

In the Bay the two best artificial structures that have been most successful at attracting fish were actually not constructed for that purpose. They are the twin spans of the Chesapeake Bay Bridge and the Liquefied Natural Gas Pier at Cove Point on the Western Shore off Calvert County. Striped bass congregate in tremendous numbers around the underwater pilings of those structures, while other species such as white perch, spot, bluefish and Atlantic croaker can be found to a lesser extent.

Of the 21 permitted reef sites in Maryland’s portion of the Bay, only a few have been proven to consistently provide good fishing for sport anglers. In some cases the materials placed on Bay sites have been covered by current-driven sand. Elsewhere, materials broke apart, dissolved, were swept away, or settled into the sediment. Still other sites remain intact and have been settled by colonial organisms, but don’t seem to attract many of the more desirable species of sport fish. The sites that have been productive offer hope that through the proper placement and orientation of material, they might become “fish magnets” like the Cove Point Pier or the Bay Bridge.

In the offshore waters of the Atlantic Ocean, success rates for attracting sport fish are much different. Nearly any kind of material that is deployed will be populated by an encrusting growth of colonial organisms, such as blue mussels, anemones and myriad others. Because much of the offshore benthic landscape is devoid of structure, fish species such as tautog, black sea bass, Atlantic spadefish, summer flounder, gray triggerfish, amberjack and others are drawn to nearly any structure that is placed in the water.

photo of decommissioned ship being sunk to create an artificial reefA variety of materials have been deployed on several reef sites, from Purnell’s Reef located from three-quarters of a mile off the beach at Ocean City to the Great Eastern Reef 20 miles offshore. In the late 1980s, the WWII-era submarine Blenny was sunk 12 nautical miles southeast of the Ocean City Inlet on the African Queen Reef site. Several other vessels, military tanks, and the freighter African Queen, which sank in a storm in 1958 and lends its name to the reef, are located in the vicinity.

In addition to sport fishermen, these reefs are destinations for scuba divers who flock to the area to spear fish, gather mussels, or shoot underwater photographs. While visibility is highly variable, under the right conditions it can reach upwards of 40 feet. This is a perfect example of an artificial reef site that provides habitat for fish and other marine life, is accessible to boaters, and provides quality recreational opportunities for sport fishermen and divers.

The Reef Ball Phenomenon
During the past four to five years, a new experimental material has emerged on the national and international reef development scene. The new devices are specialized concrete structures that resemble igloos with holes in several locations. Reef balls have been used all over the world and have been highly successful in areas such as the tropics.

Deployments began in Maryland in 2001 and there are currently a dozen sites with reef balls, all in the Chesapeake Bay. Monitoring to date has indicated that colonial organisms including sea squirts, mussels, barnacles and some oyster sets have occurred in many locations. Fishery managers will be working with stakeholders to evaluate sportfishing enhancement through angling surveys. For now, the effectiveness of reef balls to enhance sportfishing opportunities is yet to be determined.

Optimistic Outlook
Public enthusiasm for continued artificial reef development remains strong, with most support centered on the Chesapeake Bay and the Atlantic Coast. Loss of habitat in the Bay from the decline of the native oyster, siltation of historically productive areas, and loss of fishing areas to post- 9/11 security concerns has also contributed to a strong desire by recreational and commercial interests to develop artificial reefs. On the coast the phenomenal success rate of past projects continues to fuel enthusiasm for creating and expanding reef sites.

In all areas, funding is the major limiting factor. While most materials such as obsolete vessels and concrete rubble are donated, transportation costs are significant, which severely limits options for placement locations.

photo of flounder on an artificial reef courtesy of Rick YoungerMaryland’s Department of Natural Resources (DNR) is already working to determine a more effective strategy for future deployments of reef materials and establishment of new reef sites. DNR’s Fisheries Service will be convening its first Artificial Reef Committee composed of stakeholders and scientists in the fall of 2005. The Reef Committee will be tasked with developing a Maryland Artificial Reef Plan that will allow for an organized, science-based approach to marine and estuarine habitat enhancement using both natural and alternate materials. This effort will be coupled with DNR’s commitment of staff to the Atlantic States Marine Fisheries Artificial Reef Committee. That action will help with the acquisition of grants and other funding to assist with transportation and deployment costs.

To find the locations of artificial reefs in Maryland, please visit www.dnr.maryland.gov/fisheries


Martin L. Gary has worked as a Fisheries Ecologist for Maryland DNR for 20 years, and has been heavily involved in artificial reef research and development in Maryland. An avid diver, he has personally explored nearly all of Maryland’s reef sites. If you have a question for him, you can e-mail him directly at mlgary@dnr.state.md.us

Photo of Flounder on an artificial reef, courtesy of Rick Younger.

The Ocean City Reef Foundation generously provided photographs for this article.

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