They don’t start out “bald.”
Eagles reach maturity at age 4 to 5. Until then, they model varying shades of black and brown in an otherwise stark, white head, and will appear somewhat like its cousin, the golden eagle. More common in western reaches of the United States, goldens make occasional forays into Iowa, most notably northeast Iowa.
Don’t mess with those talons.
An eagle can lift and carry items up to half its body weight. With an upper-end size of 15 pounds, a large eagle could carry nearly a gallon of water. Its strength comes from leg muscles, tendons and bones. A unique relationship between the tendons and tendon sheaths creates a ratching effect within the talons, allowing the eagle to maintain its grip on prey for long periods without experiencing much muscle fatigue (HawkQuest). Although hard to judge, some research indicates eagles can exert 1,000 pounds of pressure in each foot (American Eagle Foundation), or about 10 times that of humans (HawkQuest).
They have a need for speed.
An eagle can fly 35 to 44 miles per hour solo, or about 30 mph carrying a freshly caught meal. It can dive at speeds reaching 100 mph.
They are family-oriented birds.
Eagles can raise anywhere between one to three young, with two being the most common number. An eagle will begin incubating its clutch of eggs as early as February after focusing on nest building from November to January.
They’re practically everywhere.
You’re probably well aware of the eagle’s celebratory rise from endangered status to being common. They’re so common in Iowa now, that only three counties – Union, Osceola and Monroe – have not had a bald eagle nest recorded there. The highest density of nesting eagles in Iowa is Allamakee County, with at least 88 active bald eagle territories. Last year, the bald eagle midwinter survey counted 4,957 eagles in Iowa, a record.
You can help keep track of them.
The DNR collects a lot of data on eagles, and we’ve coordinated the counting of wintering eagles during the Bald Eagle Midwinter Survey since the early 1990s. We recruit and train volunteers to monitor nesting sites during the nesting season, which starts in March. If you’re interested in becoming an Eagle Nest Monitor visit: www.iowadnr.gov/volunteerwildlifemonitoring.
Portions of this article originally appeared in the January/February 2008 issue of Iowa Outdoors Magazine.