The wingspan and shape determine a bird’s flight style. Landbirds with the longest wingspans are raptors (or birds of prey) and have similar wing proportions and flight styles, consisting of soaring and gliding with little flapping of the wings.
After the massive California condor, the bald and golden eagles are the birds with the longest wingspan in North America. These two eagles have very similar wingspan lengths and other body measurements. As is also the case with other birds of prey, female bald eagles are larger and have longer wingspan than males.
A bald eagle’s wingspan is the length between the wingtips of its spread-out wings. The concept of wingspan is also used as a measure of airplane size. Figuratively speaking, the wingspan is also used to indicate athletes’ arm breath, particularly in sports, such as basketball, where arm reach and length are important.
Each bird species has a unique wingspan.
There are over 9,000 species of birds in the world, each with its ideal wingspan. A tiny hummingbird has long and narrow wings suitable for hovering and acrobatic flight. A slightly larger songbird has shorter but much broader wings adapted for life in the foliage of trees.
The wingspan of birds ranges from a few inches in small birds to 12 feet (144 inches) in the wandering albatross.
How is a bird’s wingspan measured?
A bird’s wingspan is generally obtained from birds that have been collected for scientific research purposes. A bird’s wings are extended to the maximum extent possible to obtain the length between the wingtips before the specimen gets cold and rigid.
The wingspan can also be obtained from live birds, particularly small ones. However, live birds are restless. Keeping their wings spread long enough to take an accurate measurement can be a challenge.
Some ornithologists obtain an approximation of a bird’s wingspan by taking the length between the middle of the bird’s back to the tip of one wing fully stretched. This measure is then multiplied by 2.
The bald eagle wingspan compared to other birds of prey.
The bald eagle’s wingspan is the second-longest among the top 5 largest North American flying birds. The bald eagle shares a second place on the list with the golden eagle, which has nearly the same wingspan.
The top five birds with the longest wingspans have long and narrow wings suitable for maintaining flight without or with little wing flapping.
Birds like the California condor and turkey vulture have special tendons that allow them to “lock” their extended wings. These birds can spend long periods of time soaring and gliding effortlessly.
A bald eagle’s wingspan and shape are ideal for combining gliding with a flight that involves wing flapping. A bald eagle can also spend long periods of time soaring without flapping its wings.
When foraging for food, though, bald eagles can engage in flight that involves active and vigorous wing flapping as they swoop fish near the surface of the water or chase after other birds to take their food.
The average wingspan of a bald eagle and other birds of prey in the table below (in parentheses) is obtained from the wingspan ranges for each species given in the literature.
| Range and (average in inches) | Centimeters | |
| California Condor | 108 – 122 (115) | 274 to 310 |
| Golden Eagle | 71 – 92 (81.5) | 180 to 234 |
| Bald Eagle | 71 – 91 (81) | 180 to 230 |
| Turkey Vulture | 63 – 72 (67.5) | 160t to 183 |
| Osprey | 60 – 72 (66) | 150 to 180 |
| Red-tailed Hawk | 42 – 58 (50) | 105 to 141 |
Long and narrow versus short and broad bird wings.
Birds with narrow and long wings (long wingspans) typically do little flapping while flying. Long and narrow wings are ideal for soaring for long periods of time but are dependent on wind currents. A typical example of birds with narrow wings and long wingspans are albatrosses, petrels, and many other seabirds.
At the other end of the spectrum are elliptical and short wings (short wingspans). These types of wings allow birds to perform fast takeoffs and pick up speed in short distances. Birds with short wingspans are particularly good at sorting obstacles such as branches inside wooded areas. A typical example of a bird with a short wingspan is a Cooper’s Hawk.
The bald eagle’s wing type falls roughly on the upper half of the long and short wing spectrum. America’s National bird has long and broad wings that provide the ability to soar and glide with an active flight that includes flapping its wings. These types of wings are good for sorting obstacles at low densities. Hawks also have these types of wings.
Female bald eagles have longer wingspans than males.
In most birds, males are larger than females, but in most birds of prey is the opposite. The female bald eagle is larger and has a longer wingspan than the male.
Ornithologists suggest that such differences in size and wingspan allow male and female eagles to hunt prey of different sizes and avoid competition over prey of the same size.
Another line of thought suggests that females are larger to protect their eggs and chicks from larger predators and aggressive bald eagle males that may attack their chicks and female eagles.
The literature indicates that the bald eagle’s wingspan ranges between 5.11” feet and 7.7” feet. The lower end indicates the smallest males, while the upper end refers to the largest females in the range. However, most males have a wingspan of 6.4” while most females have a wingspan of 7.2” feet.
| Wingspan (Feet) | Wingspan (Inches) | |
| Male Bald Eagle | 6.4 | 76.8 |
| Female Bald Eagle | 7.2 | 86.4 |
The bald eagle’s wingspan varies across the species range.
The bald eagle varies in size, therefore in the length of its wingspan. Southern bald eagle populations average smaller sizes. The largest sizes and longest wingspans are found in bald eagle populations in northern states and Alaska.
Final Remarks:
The bald eagle comes second among the top five North American birds with the longest wingspan. The bald eagle’s length and shape are suitable for soaring, gliding, and flight, including the wings’ active flapping. Female bald eagles are larger and have longer wingspans to enable each sex to go after prey of different sizes and reduce competition for food between the sexes.
References:
- Dunning, Jr., J.B., ed. (1993). CRC Handbook of Avian Body Masses. CRC Press, Ann Arbor.
- Ferguson-Lees, James; Christie, David A. (2001). Raptors of the World. Houghton Mifflin Harcourt.
- Forsman, Dick (2008). The Raptors of Europe & the Middle East: A Handbook of Field Identification. Princeton University Press. pp. 21–25.
- Robertson, C. J. R. (2003). “Albatrosses (Diomedeidae).” In Hutchins, Michael (ed.). Grzimek’s Animal Life Encyclopedia. 8 Birds I Tinamous and Ratites to Hoatzins (2 ed.). Farmington Hills, MI: Gale Group. pp. 113–116, 118–119
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