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Clean water advocates could hit mother lode with mine ruling
They’re back! Migratory birds returning to Chesapeake area,Webs for Wings, and more...
Suits seek cleanup plans for waterways
If there is a creature whose sheer presence suggests that humans are ungraceful, needlessly hurried-and perhaps even less evolved-it would be the swan.
In the Chesapeake Bay region, the swan is often a reminder of human actions gone awry.
The native trumpeter swan was hunted for its feathers, meat and skin, until it completely vanished from the Chesapeake and became an endangered species. The population of the native tundra swans suffered, too.
The mute swan, on the other hand, was imported to the Bay region from Europe. It escaped to the wild and bred so successfully that it now poses management problems throughout the region.
Tundra swans are once more abundant in the Chesapeake. But the migratory trumpeter has not yet returned.
Now, an adventurous young trumpeter swan from Ohio has triggered a new technique for bringing migrant populations of wild trumpeters back to the Bay.
"It's really very exciting," said research biologist Bill Sladen. "So far, it seems to be working, but we need to continue the experiment."
Sladen, founder and president of the Swan Research Program, has studied swans for decades. He now walks the grounds of a refuge at Airlie Center in Warrenton, VA, like a father to his flock, calling to the birds in soft undertones and pointing out their names.
The lakes at Airlie and neighboring properties host about 45 trumpeter swans, tundra swans and hybrids known as "trumplings." But Sladen has a soft spot for the trumpeter.
"The trumpeter is the most magnificent of all the swans," Sladen said. "It's because of humans that they're gone, and it's up to us to bring them back. We have the potential to do it."
The trumpeter and tundra swan are difficult to distinguish in the wild. The trumpeter is the larger of the two, weighing up to 30 pounds and standing up to 5 feet tall, with a solid black bill. The tundra's bill is more likely to have a yellow spot at the base. The trumpeter also has a different voice-like the short blast of a horn.
"If they don't vocalize, they are almost impossible to tell apart in flight, or during the hunt," Sladen said.
That's a problem for young trumpeters who occasionally drift into the Bay region as scouts from the north. Unfortunately, lone trumpeters tend to be shot during the hunting season because they are easily confused with the tundras. The hunting of tundra swans is legal in some parts of Virginia.
Trumpeters once roamed all of North America, breeding in northerly areas during the spring and migrating south in the winter. Scientists believe their numbers may have reached 130,000 before European settlement.
Then the bird became popular prey. The market at home and abroad had an insatiable appetite for its meat, skin and feathers, which were used for quills and hats.
"They were completely wiped out in the East," Sladen said. By 1932, only 69 were accounted for in the lower 48 states, most of them in Montana.
Conservation efforts helped the trumpeter recover, but not to its former glory.
There are now about 19,000 North American trumpeters in three populations. The Pacific group breeds in western Alaska and migrates south into British Columbia and Washington state. The Rocky Mountain group is centered on the Red Rock Lakes National Wildlife Refuge.
Trumpeters to the east make up the interior population. These reintroduced swans are basically non-migratory. However, they are learning a route by trial and error through the work of young birds that are slowly exploring new territory.
In the Bay region, trumpeters mostly live as grounded birds at Airlie, bred from parents in other places.
They do not migrate. Swans must learn migration from their parents, but the parents of today's swans don't know where to go. Neither do their offspring.
The Airlie trumpeters are wing-clipped, which temporarily renders them flightless until scientists are ready to conduct migration experiments.
"When single birds get into different places, they tend to get killed," Sladen said. "That's why we have to show them a route of our choice or teach them to follow the traditional route of the tundra swan. We have to show them the safe way to travel."
In the 1990s, Sladen was among a group of pioneers who taught migration routes to Canada geese and trumpeter swans in the Bay region by training them to follow an ultralight aircraft. They met with some success and inspired the movie, "Fly Away Home."
Operation Migration, a nonprofit organization, continues to use the ultralight method with whooping cranes and sandhill cranes. But Sladen said that ultralights became too impractical and too expensive for the trumpeter swans.
Trumpeters compete for position in the air. When flying near an ultralight, this poses risks to both birds and pilots. Trumpeters also need an updraft to lift their larger bodies, while ultralights fly in calm conditions.
"The Swan Research Program abandoned the ultralight technique in 2001 because it was dangerous, much too expensive and took an unnaturally long time," Sladen said.
Enter trumpeter swan "0A4." The young male, banded with this code in Ohio, made a surprise appearance at Airlie in the winter of 2005.
He didn't learn the route from his parents, or from an ultralight. He learned it by following the tundra swans.
"He came in with 12 wild tundra swans, then met up with our resident trumpeters and was happy," Sladen said. "The next year he came again."
This time, he brought a female partner. Over the next two winters, he arrived with a few other trumpeters, in different combinations.
On his third visit, the male broke with his partner to pair with a female trumpeter in the Airlie collection. "A typical teenager," Sladen said.
He didn't leave for the spring migration.
By June, Sladen's team collected the pair and moved them to Ohio by truck, along with two other pairs from Airlie.
"We put them in with the Ohio group and prayed," said biologist Sean Campbell, who nurtures the swan habitat at Airlie and tracks the movements and behavior of the swans.
In January 2009, "0A4" returned to Airlie with his Airlie partner. With him were the female that had accompanied him on the first trip, her mate, their youngster, an unmarked pair and one of the four Airlie swans transported to Ohio by truck.
"So before spring migration, we had at Airlie eight trumpeter swans, two of which were Airlie-raised swans that learned a round-trip route of about 500 miles between the Ohio breeding grounds and their wintering grounds in North Virginia," Campbell said.
The observations prove that trumpeter swans can learn migration from tundra swans, even if it happens rarely.
"The tundra swans fly at the right elevation, duration and time, when the trumpeter swans would normally do it," Campbell said. "So we'd like to see more of the trumpeters learn from their peers, and then breed and teach their young."
If the Swan Research Program can nudge this process along, they may have a solution that is both cost-effective and safe. They are working with David Sherman with Ohio's trumpeter swan reintroduction program and the Shenango Wildlife Area to make it happen.
Their goal is to stage tagged trumpeter swans at points along the tundra migration route, in the hope that the trumpeters will join up with the tundras.
"It's an imprinting process that starts with the young," Sladen said. "We would take these young birds, possibly with their parents, into the flyway where we know they will be cavorting with the tundras that are coming back to Airlie."
Key to that plan is a high-tech tracking device on the swans' neck tags, so that biologists can place the trumpeters at good spots.
"We need satellite telemetry to find out exactly where the wintering tundra swans go," Campbell said. "After we study this further, we might have the potential to take the Airlie trumpeters even farther north than Ohio."
But while "swans-teaching-swans" costs less than an ultra-light, the bill for providing and monitoring a satellite transmitter runs about $5,000 per bird. A few lucky tundra swans already sport the device.
The search for more funding is under way, with help from a regional advisory team. The team will include swan experts from Virginia, Ohio, Wisconsin and Minnesota, as well as federal representatives and scientists who conduct similar work with whooping cranes.
The project must also be approved by state and federal agencies.
Gary Costanzo, who manages the migratory game bird program for the Virginia Department of Game and Inland Fisheries, appreciates the allure of the trumpeter swan, but suggests proceeding cautiously. The reintroduction of trumpeters to the Bay ecosystem raises unanswered questions.
"The environment has changed a lot since trumpeter swans were here," Costanzo said. "We have less SAV; other critters have moved in; and it's not a pristine environment."
Trumpeters would join the flocks of resident mute swans that feed on Bay grasses and resident geese that linger on farm fields. Even if led to the Bay by migration, some might choose to stay year-round.
"We're concerned about where they will go, and what they will eat," Costanzo said.
The trumpeter would also impact the hunting community, including repercussions for those who-knowingly or not-shoot a trumpeter.
"These issues need to be addressed," Costanzo said.
Other East Coast waterfowl are managed cooperatively through the Atlantic Flyway Council, which involves the eastern states and Canadian provinces. The council does not yet have a management plan for the trumpeter swan.
"If the swans are reintroduced, we want it done the right way, with proper safeguards," Costanzo said. "We need to think about how they are going to fit in the big picture-and in the ecology of the Chesapeake Bay."
Despite the challenges, restoring migration routes is important to the trumpeter's long-term survival. As the number of resident trumpeters continues to grow, they will compete for food and habitat in localized areas and could, like the non-native mute swan, become undesired.
Migration helps to sustain the population by spreading the demand for food and breeding grounds to different locations throughout the year.
Sladen said that the first steps are small but vital.
"We need to make sure that we have more than eight birds coming back and forth from Ohio. That's a very small flock," Sladen said. "But ultimately, our ambition is to get them back into the Chesapeake Bay."
