Maryland Controls Mute Swan Population

Maryland to Continue to Control Mute Swan Population

Maryland Department of Natural Resources
Maryland Department of Natural Resources

ANNAPOLIS, MD – In response to recommendations of the majority of the members of Maryland’s Mute Swan Task Force, the Maryland Department of Natural Resources (DNR) will continue to reduce the Chesapeake Bay’s population of non-native mute swans. Because of the State’s successful control efforts, there are far fewer mute swans in Maryland today than there were a few years ago; about 500 remain of a population that had reached nearly 4,000 a decade ago.

In the spring of 2009, DNR convened a group of environmentalists, scientists, animal advocates, and other stakeholders to revisit the Mute Swan Plan and develop a recommendation for how Maryland should proceed. That group split over the issue of lethal control of adult mute swans and presented two contrasting reports. One report, from two animal rights members, advocated maintaining a population of mute swans in the Chesapeake Bay. The report from the other 10 members, including scientists, conservationists, and State and Federal agency representatives, argued for the continued reduction of mute swans. Both reports may be viewed at:

“While the swans may be beautiful, they continue to pose a serious threat to the Chesapeake Bay and its native wildlife, and non-lethal controls have proven insufficient for reducing the population,” said DNR Secretary Griffin. “For these reasons, we are unfortunately compelled to continue Maryland’s mute swan control efforts, through both non-lethal and lethal means.”

“After reviewing the reports and considering the best advice of my staff and the scientific and environmental communities, I have found the case for continued controls ecologically crucial and in alignment with both the 2000 Chesapeake Bay Agreement invasive species control plans and Maryland State law,” the Secretary added.

Jonathan McKnight, the Maryland DNR Biologist who coordinated the Mute Swan Advisory Committee said, “There is a solid body of scientific literature demonstrating that this species — like the nutria, a marsh rodent from South America — causes harm to native species and the Chesapeake ecosystem.”

Environmentalists and conservation groups praised the decision, which the animal rights groups PETA and the Humane Society of the United States had lobbied against.

“We support the DNR in making this difficult decision”, said Kim Coble, Maryland Executive Director of the Chesapeake Bay Foundation. “It’s controversial, but it’s the right thing to do to protect important Chesapeake Bay resources.”

The Maryland Ornithological Society, which has supported mute swan control because of the tendency of mute swans to drive declining native birds from their nesting grounds, was also pleased.

“This was clearly the right call for the resource and I’m impressed that DNR moved quickly to make this decision,” said MOS President Dr. Wayne Bell. “Maryland has achieved an unparalleled 80 percent reduction in the population of this invasive species, so to stop now would have made little sense.”

Mute swans are native to Europe and Asia. Maryland’s population of mute swans originated when five birds escaped from captivity in Talbot County in 1962. Currently, about 500 mute swans remain in the Bay and its tributaries. They are now established in all major tributaries to the Maryland portion of Chesapeake Bay. Mute swans have caused adverse ecological impacts by driving out nesting native waterfowl and the removal of submerged aquatic vegetation (SAV) during the summer, fall and spring when SAV are reproducing; and the destruction of SAV restoration and replanting sites.

Mute swans are one of six species identified in the Chesapeake Bay Agreement as priority invasive species that threaten the Chesapeake ecosystem.

The Maryland Department of Natural Resources (DNR), which this year celebrates its 40th anniversary, is the state agency responsible for providing natural and living resource-related services to citizens and visitors. DNR manages more than 449,000 acres of public lands and 17,000 miles of waterways, along with Maryland’s forests, fisheries, and wildlife for maximum environmental, economic and quality of life benefits. A national leader in land conservation, DNR-managed parks and natural, historic, and cultural resources attract 12 million visitors annually. DNR is the lead agency in Maryland’s effort to restore the Chesapeake Bay, the state’s number one environmental priority. Learn more at