LINCOLN — The eagles truly have landed.
A record 103 active bald eagle nests were recorded in Nebraska this year, surpassing the previous record of 90 set in 2011.
In Iowa, a record 222 bald eagle territories had active nests, up from 213 last year and 76 in 1998. Audubon County in southwest Iowa reported its first confirmed nest this year.
“Even though we say the recovery of the bald eagle in the United States and Nebraska has been remarkable, it truly has been amazing,” said Joel Jorgensen, nongame bird manager for the Nebraska Game and Parks Commission.
Bald eagles have been increasing as a breeding species in Nebraska and Iowa for two decades, but the jump in the number of nests observed in recent years has been partially due to additional survey efforts.
After a couple of years of less-intense focus, Nebraska Game and Parks crews spent a few days in 2011 and 2012 surveying areas that had not been checked for a few years.
“It did not come as a surprise to us that those areas were harboring additional nests,” Jorgensen said.
Nesting activity, however, does not imply breeding success.
From the 98 territories for which the Iowa Department of Natural Resources has information, a total 151 young were produced. That averages to 1.54 young produced per nest. Assuming that the 86 percent of all nests reported as active would be successful, Iowa nests produced an estimated 294 young this year, said Stephanie Shepherd of the Iowa Natural Resources Department's Wildlife Research Center in Boone.
An Iowa eagle territory is a habitat area up to one mile in radius that is defended by a pair of eagles and used for breeding.
Nebraska quit collecting productivity information about three years ago to focus on finding and monitoring active nests, Jorgensen said. Still, he said, it's a safe assumption that the trend of 1.4 to 1.5 fledglings per nest has continued.
Most eagle nests in Nebraska and Iowa are concentrated along major rivers. The first successful modern bald eagle nest in Nebraska was found in 1991 in Douglas County.
Historically, bald eagles have nested in Nebraska, but they were wiped out around 1900. Jorgensen said it is possible that bald eagles are more common now than before the settlers came.
In Iowa, nesting pairs have grown exponentially, making it difficult to track them, Shepherd said. Biologists developed a more standardized nest-monitoring plan a few years ago to keep better tabs on bald eagle productivity and population.
The plan involves monitoring a random selection of bald eagle territories known to have had nesting activity in the past three years.
In addition to estimating how successful and productive eagles are across Iowa, the observations will give biologists warning signs if something is going wrong, Shepherd said.
The recovery of the bald eagle is considered a modern conservation success story. The eagle was listed as a federally and state endangered species in 1978.
Bald eagle populations declined greatly throughout the 20th century primarily because of the use of the insecticide DDT and similar chemical pesticides. In 1963 there were fewer than 500 breeding pairs in the lower 48 states. After the banning of DDT and many years of intense management efforts, the bald eagle was removed from the federal list of threatened and endangered species in 2007 and the Nebraska list in 2008.
Still, bald eagles face old threats, such as habitat loss, and new challenges, such as lead poisoning, Shepherd said.
Bald eagle nest monitoring in Nebraska is conducted and coordinated by Game and Parks but also relies on cooperating agencies and trained volunteers to collect data.
Iowa hopes to recruit and train more volunteers as part of a goal to collect information on at least 25 percent of the state's active territories. A training video for nest monitors has been produced and should be available on the Iowa Natural Resources Department's website yet this month.
Tips If you go: Public eagle-watching opportunities are available this winter at sites in central and western Nebraska
» The sites: the J-2 hydroplant near Lexington; and below Kingsley Dam near Ogallala. There is no charge.
» A limited number of binoculars are available at the sites. Visitors are encouraged to bring their own viewing equipment.
» The best viewing time is normally early in the day.
» Several factors influence the number of eagles seen from the facilities on any given day, including weather conditions, ice coverage on area bodies of water, how many eagles are wintering in the area, and whether the hydroplants are online.
» Eagles are attracted to feed on fish in the open water below the plants, particularly when rivers and lakes in the area are covered with ice.
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