Tundra swans breed in the Arctic during warmer months. In North America, they are grouped into Eastern and Western populations. The Eastern band travels more than 4,000 miles to winter in coastal areas from Maryland to North Carolina — mostly the latter nowadays.
Annual surveys conducted by the U.S. Fish and Wildlife Service typically count 90,000-100,000 birds in the Eastern population, but their numbers unexpectedly dropped from a record high of 137,000 in 2023 to a 45-year low of 64,000 in 2024. Wildlife officials chalk up that decline to normal annual variation and not to any specific factors or threats.
As recently as the 1960s, the tundra swan population in North Carolina only numbered in the low thousands. In recent decades, the state has averaged approximately 65,000-75,000 wintering tundra swans, mostly in and immediately around the neck of land between the Albemarle and Pamlico sounds, Morris said. He suspects that the birds found the region more hospitable after many of its forests were plowed under for cropland, offering them a ready food source. “We had swans, but nothing anywhere near like it is now,” he said.
But that influx might not have happened if not for concurrent changes in the Chesapeake Bay’s fragile ecosystem, according to Morris and other experts.
The Bay’s water quality had been on the decline for many years largely because of increasing nutrient and sediment pollution flowing off city streets, suburban yards and farm fields during heavy rain. The biggest turning point came in 1972, when the remnants of Hurricane Agnes triggered widespread flooding and a multi-decade downturn in the Bay’s health.
The cloudy water in the Bay and its tributaries smothered much of the underwater grasses that had fed and nourished generations of tundra swans, said Kayla Harvey, waterfowl program manager for the Maryland Department of Natural Resources. As their preferred food dwindled, tundra swans began feeding in farm fields on waste grains, such as corn and soybeans.
By the 1980s and ’90s, North Carolina surpassed the Chesapeake as the population’s most important wintering ground.
Hunting pressure doesn’t appear to have impeded that trend. While Maryland legislators tried to legalize hunting the birds, arguing that it would bring in permit revenue, the bill died in committee. North Carolina, though, is among 10 states (including Delaware and Virginia in the Bay watershed) where tundra swan hunting is allowed. Because North Carolina has the largest population, the state receives the lion’s share of the federally allocated permits for the Eastern region — usually around 4,800 of the 5,600 total.
Bringing more tundra swans back to the Chesapeake will require continued efforts to revive its ecosystem, Harvey said. The biggest determinant will be increasing underwater grasses through actions such as direct seeding and improving water quality to support more growth, she added.
There used to be a pretty reliable small flock of Tundra Swans that occupied the shallow bar area between Matoaka Cottages and Western Shores to the north of us for the winter season. In the the last few years, I would say 5 or so, there have been only the occasional swan up there. I think I only saw a couple of them up there once this winter.
It's curious that they seem to be blaming a recent decline in the swans in the Bay region to water quality, which the Bay program would insist has seen a measurable, if small improvement due to the $25 billion or so spent to clean up the bay.
The emphasis on SAV seems misplaced too. In North Carolina, their increase is credited to more farming, Could it be the decline here could due to a decrease in farming, and an increase in suburbs
Meeting the Chesapeake Bay’s underwater grass restoration goal could soon get more difficult.
The state-federal Bay Program partnership may increase its goal for underwater grasses, an important habitat for blue crabs and many other species, from 185,000 to 196,000 acres.
Even the smaller of those numbers is more than double what’s been observed in the Bay in recent years, and the region has never come close to the 185,000-acre figure since Baywide measurements of the grass beds — officially called submerged aquatic vegetation, or SAV — began in the early 1980s.
Nonetheless, scientists and state officials say the goal should be updated to better reflect the amount of potential SAV habitat if the region meets its pollution reduction goals in the future.
The Bay Program established the 185,000 figure in 2003 using photographs from aerial surveys conducted during the 1900s — mostly old agricultural surveys — to map the location of all grass beds that could be seen in different parts of the Bay at some point in time.
Brooke Landry, a biologist with the Maryland Department of Natural Resources and chair of the Bay Program’s Submerged Aquatic Vegetation Workgroup, said that when the original maps were drawn, portions of some shoreline grass beds were inadvertently cut off in the mapping process, resulting in an underestimation of the observed amount.
Also, grass beds have been observed in recent years in some locations where they had not been previously mapped.
When those areas are included, the extent of Bay bottom that supports SAV, or is known to have done so at some point in the last century, increased to about 196,000 acres.
That updated figure is being proposed as a goal for the revised Chesapeake Bay Watershed Agreement, the policy document that guides Bay restoration efforts, which is being updated this year.
Landry acknowledged that meeting the goal will be difficult. While 196,000 acres of the Bay may have supported SAV at some point in time, it’s unclear whether that much ever existed in any single year during the past century.
The greatest extent of grass beds observed in recent decades was about 108,000 acres in 2018. Since then, the amount observed in annual aerial surveys has ranged from roughly 63,000 to 83,000 acres.
So we're nowhere near the current goal, and they're proposing to increase the goals for the next go around. Seems like a pretty sure way to achieve failure the next time around. And do we really have any specific mechanism proposed to increase SAV, beyond further restricting nutrients?
The Wombat has Rule 5 Sunday: The Last Champion of Cracker Barrel up at the Other McCain.
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