Iowa bird enthusiasts have had ample opportunity this winter to observe the state’s largest and — many would say — most striking avian resident, the trumpeter swan.
Once extirpated from Iowa, the birds named for their haunting call have been concentrating recently at Prairie Park Fishery in Cedar Rapids, at Crescent Pond in the Hawkeye Wildlife Area in Johnson County and on Lily Lake near Amana.
“We’ve had a huge influx of swans from Minnesota and Wisconsin and a record number wintering in Iowa,” said Department of Natural Resources wildlife biologist Dave Hoffman, who coordinates the state’s trumpeter swan reintroduction program.
The DNR’s annual January count recorded 1,823 swans, a 63 percent increase over the number counted last year, Hoffman said.
Beemer’s Pond west of Fort Dodge, typically ground zero for wintering swans, had this year’s largest concentration, 360 swans, followed by Dale Maffitt Reservoir near Des Moines with 262 swans and Lake 4 near Atlantic with 135.
Hoffman said swans were counted in 30 different counties, which compares with five or six counties in a typical winter. “We had a mild winter, with open water available in many parts of the state,” he said.
Their presence in large numbers attests to the success of the state’s swan reintroduction program, which is close to attaining its goal of establishing a sustainable wild population.
ARTICLE CONTINUES BELOW ADVERTISEMENT
The state now has about 50 wild nesting pairs raising about 80 cygnets to flight stage each year. About 70 percent of the hatchlings survive to flight stage, but many of the survivors succumb to power line collisions, lead poisoning, predators, disease and even shootings before females reach sexual maturity at age 6.
Hoffman said he thinks 60 wild nesting pairs would assure the swans’ future in Iowa.
Successful nests have occurred in at least 22 of Iowa’s 99 counties, mostly in north-central and east-central Iowa. Tagged Iowa swans have been observed in many states and Canadian provinces.
Hoffman said 1,172 swans have been released since the reintroduction program began in 1993. Pairs of swans are typically released in partnership with environmental groups such as county conservation departments. The releases often coincide with the creation or improvement of the wetlands into which the swans are released.
Releases will continue for at least a few more years, with establishing successful breeding pairs in southern Iowa a top priority.
Swans typically colonize new territories to the north of their release or hatch site, making it unlikely that offspring of successful nests would settle in southern Iowa, he said.
Hoffman said the DNR plans to release 14 swans in April and May at Lake Icaria and Lake Anita, both in southern Iowa.
Before the reintroduction, the last nesting pair of trumpeters in the Iowa wilds was seen in 1893 in Hancock County in north-central Iowa. The birds became extinct in Iowa because of the drainage of wetlands for farm production and because the big birds were shot for food and feathers before the turn of the century.
After the reintroduction program began, DNR officials documented that three cygnets hatched in 1998 from a wild nesting pair in Dubuque County. That same pair hatched five cygnets in 1999 and 2000.
Trumpeter swans, the only swans native to Iowa, are North America’s largest waterfowl, weighing up to 30 pounds with a wing span of 7 feet.
Here is a look at annual trumpeter swan count numbers in Iowa since 2010, as reported by the Iowa Department of Natural Resources:
2010 — 193
2011 — 481
2012 — 747
2013 — 458
2014 — 582
2015 — 1,121
2016 — 1,823
Report swan sightings
The Iowa Department of Natural Resources encourages the reporting of trumpeter swan sightings. Information obtained through these observations helps officials track birds, learn about reproduction and gain knowledge about survival and habitat utilization. The public an help by reporting sightings of marked trumpeter swans. Here is how:
l If you see a marked swan, note the color and code on its tag, as well as the location of the tag (neck-collar, wing marker or leg band). Examples might be “Red JO5” or “Green 6F2.”
l Print the Trumpeter Swan Observation Form, available at iowadnr.gov.
l Return the completed form to: Iowa Department of Natural Resources, 1203 North Shore Drive, Clear Lake, IA 50428.
l You can also call the DNR Office at (641) 357-3517 or send email to firstname.lastname@example.org.
All observations that include a verifiable code are to receive a response with information on the bird. More than 4,000 observations of Iowa released trumpeter swans have been reported from places as far away as Colorado, Virginia, Texas and two Canadian provinces.