Bald Eagle Migration
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Travels of Destiny & Thunderbird into Ohio and the Great Lakes, beginning in Tennessee. © American Eagle Foundation.
How do bald eagles find their nests from season to season?
Eagles are diurnal (daytime) fliers, and we believe they use familiar landmarks to guide them to the general area, and once there, use more familiar and specific cues to find their particular lake and then the nest tree. Such cues as extensive mountain ranges, or large bodies of water or the coastline might first be used.
These birds obviously store great amounts of information or memory of the landscapes in their lives, as they easily move 50 – 100 miles in a winter day in search of food. – PN
How do migration patterns differ between Southern and Northern Bald Eagles?
Normally we think of migration in terms of birds flying from the north or south, depending on the time of year. For many birds, and many birds of prey, that is true. But for bald eagles, it’s not that simple! There are several factors that come into play – Food availability, age of the bird, and where it lives.
Some biologists do not characterize bald eagles as migrants, preferring to describe their travels as seasonal movements. This is because nesting bald eagles usually only move away from their nesting areas as far as they need to survive, meaning in order to find the food
So why do some eagles migrate, while others do not? First, let’s start with age.
Bald eagles that are a part of a breeding pair usually remain close to their nesting territories throughout the year. Though in some regions, they may migrate with the seasons. This difference is all based on the availability of food.
Northern adults may set out on the fall migration when lakes and rivers begin to freeze over, usually returning to breeding territory when weather and food permits. Interestingly, they don’t necessarily head south to reach the more temperate regions, but they will travel in several directions to find open waters.
Breeding age eagles are often referred to as floaters. Floaters typically wander within the geographic location from where they hatched and migrate seasonally using the same route used in their earlier years. The floaters wandering is likely tied to a search for nesting habitat, and of course, a mate.
These floaters have been known to move in quickly to take the place of the missing mate – sometimes within just a few days.
Other information on bald eagle migration –
Wind currents play a role in the bald eagles flight pattern. During migration, eagles will ride columns of rising air called thermals and can average speeds of 30 mph.
Some telemetry studies have shown that migrating eagles can fly as many as 225 miles in a day. The average distance per day was about 98 miles.
During migration, what is the average distance an eagle flies in a day?
Usually between 75 – 125 miles, but weather affects that estimate. – PN
When eagles get ready to fly long distances, do they eat a lot for energy or eat less for weight loss?
Prior to migration eagles will eat normally; they do not fast for weight loss. They may even tend to eat more to load up if food is readily available. We have witnessed migrating eagles stocking up on food en-route also. If a migrating bird comes across a deer carcass, for example, it might hold up its migration for a day to feed up on the available food. – PN
If an eagle is relocated, does this affect their migration path?
This refers to eagles taken to a hack tower at a young age for release in another location from where they were hatched. The ‘hacking’ program is based on a well-known concept in avian biology called ‘fidelity,’ and specifically in this case fidelity to birthplace. In the case of hacking, we rely on this concept to predict that young eagles brought to hacking towers at an early enough age, believe this is their nest site, and orient to this site / area once they fledge.
In a nutshell, we now know that eagles that fledge from hacking sites, think this is home, and return to this general area once they reach sexual maturity for their own breeding. – PN
What is the bald eagles’ migration path?
The answer to this depends on: 1) where the birds are from; 2) where they are wintering; 3) their age; and 4) the season.
Some eagles don’t migrate at all. If they live in an area where they can survive all winter (one with plenty of open water and food), they will stay close to their nesting area and not move far at all.
If they do have to move to find open water and food, generally they will only move as far as they need to find a suitable over-wintering area that meets their needs.
Young eagles, not yet adults, may move in more random directions than adults that have developed strong habits, returning along the same routes to the same wintering and nesting areas year after year.
In the spring, adult eagles departing their wintering area usually follow a pretty direct route to their nesting area, wanting to get back quickly to reestablish their territory and initiate breeding.
In the fall, these eagles are in no such hurry to get back to the wintering area, and take a more leisurely route, not as direct and taking longer. Furthermore, adult eagles will return to their same wintering site, over and over again. – PN
Do bald eagles migrate in flocks?
No, eagles migrate alone as far as we know. Although, they could happen upon other eagles during their travels.
• On August 2, 2013, the AEF released two 13-week-old eaglets from our hack tower on Douglas Lake in Tennessee. These eaglets, Destiny & Thunderbird, were equipped with GPS tracking devices. Unfortunately, the tracking devices became unresponsive after a few weeks and we were no longer able to track them. However, in just a few days, Destiny traveled to Ohio, and Thunderbird made it all the way to Lake Huron, close to the Canadian border. We have since had several sightings of Destiny, who was identified by her patagial wing tag, L3. A reported sitring of Destiny on August 30, 2015, showed that she was still doing well. In 2020, we received a report that Destiny is now nesting in TN.