Who's Who?

Wait, this is an eagle cam, not an owl cam. What’s with all the hooting? No, this is not about owls! But if you’re watching the eagles in the nest, you might be wondering who’s who. As you’re watching the adult eagle incubating the eggs, or even feeding the young eaglets, it can be difficult to tell who’s who. You see, both mom and dad eagle share responsibility for these tasks. The female does most of the incubating, and staying on the nest with newly hatched youngsters. But she will leave for periods of time to find food for herself, and also provide for the young. But given that it can be pretty cold in March and April, when eagles in this area are incubating eggs and tending to those newly hatched young – at least one of the adults needs to be there to keep the youngsters warm. So, how can you tell who you’re seeing? Well, it can be difficult. Both the male and female adult eagles will have a full white head and tail. It takes an eagle 5-6 years to have that white head and tail, and that is the mark of a sexually mature eagle. The only visual difference between males and females is size. And in the eagle world, as in most birds of prey, the female is significantly larger than the male. A female bald eagle is usually about 1/3 larger than the male. Her wingspan be longer and she will weigh 2-3 pounds more. This phenomenon in eagles is referred to as reverse sexual dimorphism. Reverse because it is different than the way things work in humans and many other mammals where the males tend to be larger than the females. Sexual, because the difference is seen between the sexes. And dimorphism – which means that there are two different sizes (or colors or shapes, etc.) represented. The male and female eagles take turns warming the eggs and tending the young. But, many times only one of them is there. So it can be difficult to know if you are seeing the male or the female, without the other one there to compare size. If you do get a chance to see both on the nest together, you can take the opportunity to look for distinctive features that might help identify one or the other in the future. And keep an eye on those chicks when they hatch, soon you’ll be able to identify the whole eagle family! Eileen Hanson Program Specialist


Wabasha, MN