For some raptors, mating season starts early!

Written by: Ashley Nilsson

Bald Eagles and Great Horned Owls are some of the first birds in Wisconsin to begin their courtship and mating. While other animals are hunkered down and trying to use as little energy as possible during winter, these raptors have something else on their minds… Babies! Let’s look at what their mating season entails.

Bald Eagle Mating Behavior

Mated pair of bald eagles in their nest

  • Bald Eagles mate for life, using the same nest each year.
  • In Wisconsin, eggs are laid between February and April.
  • Their nest can weigh over 1,000 pounds and averages between five to six feet in diameter and two to four feet tall!
  • They reach sexual maturity at five years old, but in areas where the eagle population is high, sexual maturity occurs at ages six to seven years old.
  • Bald eagle courtship involves not just preening (grooming each other), perching together, and beak rubbing but also maintenance on their nest.
  • To seal the deal, they do a “dance” in the sky known as a cartwheel courtship display or flight.
  • This “dance” involves both the male and female flying high into the sky, locking talons, and spinning down towards the ground in a cartwheel-like fashion. They release themselves from each other’s grasp before hitting the ground.
  • Once their dance is complete, copulation occurs. Between 5 and 10 days later, the female lays 2 to 3 eggs.
  • Both the male and female take turns incubating the eggs, and roughly 35 days later the eggs begin to hatch.

 

 

Great Horned Owl Mating Behavior

Two paired great-horned owls on a branch

  • Great Horned Owls, like many birds, are monogamous, only finding a new mate if something has happened to their previous mate.
  • Courtship can begin as early as October with single males looking for a partner, hooting vigorously to get the female’s attention.
  • During the last few weeks of the male calling out for love, the female will begin to call back.
  • Already paired owls will begin to hoot back and forth not only to establish that this is their territory but also to bond with their mate.
  • Whether they have been with their partner for a long time, or it is their first time with their partner, males will do a “dance” where they bob and bow in front of the female.
  • Once the male has shown the female his moves, they rub their beaks together and preen one another.
  • Once the courtship has taken place, they seal the deal by copulating.
  • Copulation lasts roughly 4-7 seconds, with both owls vocalizing the whole time!
  • Great Horned Owls do not make their nests but rather use abandoned nests of other birds like Red-tailed Hawks.
  • The female lays 2-4 eggs over the course of seven days.
  • She will incubate the eggs for roughly 35 days in frigid temperatures, with the eggs hatching as early as March!
Mated great-horned owls preening eachother
Wild adult pair of Great Horned Owls facing each exhibiting mating behavior.
0