Your questions, answered! Does DM2 learn from Mom? Will just one copulation fertilize all of Mom’s eggs?

As part of our first egg fundraiser on February 28, John took questions from watchers over at Explore.org. A follower asked whether DM2’s maturity was the result of learning from Mom or his instincts maturing as he matures. We often talk about learning and instinct, as opposed to learning versus instinct. While instinct appears to take a bigger role in eagle behavior, eagles also learn. John’s answer:

Much of an eagle’s behavior is innate. Instinct guides a wide range of behaviors, including shooting poop out of the nest, bringing in sticks to the nest, incubating eggs, and even flight. But instinct doesn’t rule out learning, which happens by experience and interaction with other eagles and even other raptors. Siblings establish a pecking order and begin refining eagle table manners like mantling, hissing, and stealing before they leave the nest. Hatchling birds instinctively vocalize, but they learn adult songs, calls, or grunts from their parents, and some songbirds appear to ‘practice’ their songs in dreams. Eagle parents and falcons use food to train their young. They play chase or tag with young, building on and improving innate flight and hunting skills. Instinct versus learning? No: learning builds on instinct.

Remember last year when it took three days for DM2 to begin feeding his young? A lot of people wondered if he would ever start. When he began, he often fed himself or tried to feed them bites that were too large. He sometimes seemed to be struggling to get food in their beaks. Feeding his young was instinctual, but he became a better and more confident feeder through experience.

Did DM2 also learn from Mom? We don’t know for sure. Eagles, like many other birds, imprint very strongly on their parents. Watchers know that imprinting includes imitating. We often see eaglets playing house, grabbing sticks and nesting material, picking at prey, and doing what their parents and siblings do. It seems reasonable to conclude that DM2 learned through experience and by watching and imitating Mom, although we have no idea which – if either – plays a larger role.

Some interesting reading:

We were also asked if fertilization need to occur between every egg. Can Mom Decorah produce multiple fertilized eggs with just one successful copulation event? John’s reply:

One successful copulation event can fertilize multiple eggs, since sperm successfully transferred during copulation make their way into the folds of the oviduct and can remain viable over a week in time. RRP Board member Jim Robison, who breeds falcons, says that goshawks can store sperm for up to two weeks. But I see this as more of a theoretical question, because our eagles are copulating on and off camera many times between each egg. To learn more about the fertilization and egg production process, check out this blog: https://www.raptorresource.org/2020/01/29/how-long-does-it-take-a-bald-eagle-to-lay-an-egg/

Fun Fact

Two weeks is a long time to store sperm, but honeybee queens can store sperm for up to four years! Read more about it here: https://www.perfectbee.com/learn-about-bees/the-science-of-bees/honey-bees-reproduce and watch a honeybee hive at Explore.org: https://explore.org/livecams/honey-bees/honey-bee-hive-cam.