Do eagles free fall when mating?

Do bald eagles mate in mid-air? Do bald eagles mate through their feet? We’ve been asked those questions on facebook, via email, and at Ustream. The short answer? No. Bald eagles do not mate with their feet or during ‘nuptial flight’. They mate by touching cloacae – the cloacal kiss – while perched securely on a tree limb or in the nest. The male mounts the female’s back, twisting his tail under hers. The two press their cloacae together and sperm passes from his cloaca to hers. As we’ve seen in Decorah and Fort St. Vrain, mating is brief, intense, and takes place fairly frequently while the eagles are in season. Most readers have probably heard of the bald eagle’s whirling nuptial flight. Mates or courting pairs lock talons and whirl through the air, disengaging before they hit the ground. Writers have suggested that this particular courtship activity might prove flight skill, test pair commitment, and/or arouse the eagles to begin mating. While these are lovely ideas, reality is much more complicated. Courting eagles do lock talons and whirl, but so do immature eagles, adult/immature eagles, and adult eagles who (presumably) aren’t courting.

Brett Mandernack, the biologist at Eagle Valley, suggested that immature eagle talon locking and whirling flight might be a precursor to adult courtship behavior. While some locking and whirling appears to be antagonistic in nature, like the two adult eagles who crash-landed in Duluth in May of 2013 (http://www.usatoday.com/story/news/nation/2013/05/14/eagles-crash-land-minnesota/2159079/), some is not. Brett has watched territorial adults repeatedly lock talons and whirl, separating before hitting the ground and soaring upward to lock talons and whirl again. “Why,” he asked “would mated adults keep locking and whirling if the behavior was solely antagonistic?” Eagles display remarkable plasticity, varying their behavior in response to environmental changes, including the presence of other eagles. Perhaps talon locking and whirling flight can be made to serve a number of purposes, including courtship. Only the eagles know for sure.

We know that eagles who retain a nesting territory and partner are more productive than those that don’t. But to get to that point, an eagle must first settle in a particular area (probably not too far from its own birthplace), establish a nesting territory, and acquire a mate. Soaring displays and vocalization might help an unpaired eagle attract a mate (look at me!) and demonstrate territorial occupation (this is my place!). Talon-locking followed by whirling flight might provide a non-aggressive response to a potential partner, indicating serious interest. If the eagles pair, food gifts and other courtship activities will quickly follow. In Decorah, courtship activities begin in late fall. Mom and Dad bring sticks and branches into the nest, eventually adding soft nesting material as courtship deepens. Food is (often) shared. The eagles vocalize together, spend more time in close proximity, and gently peck and foot to indicate their interest in one another. In late January or early February, all of this activity will culminate in copulation, with egg-laying beginning roughly 2 weeks later.

Lake Pepin is a great place to watch eagles soar and talon lock. Go the National Eagle Center’s website for more information about eagle watching on the big lake: http://www.nationaleaglecenter.org/

Sources Personal Communication, Brett Mandernack Interactive Behavior among Bald Eagles Wintering in North-Central Missouri Curtice R. Griffin The Wilson Bulletin, Vol. 93, No. 2 (Jun., 1981) , pp. 259-264 Published by: Wilson Ornithological Society Article Stable URL: http://www.jstor.org/stable/4161465 Lifetime Reproductive Success of Bald Eagles in Northern California / Éxito Reproductivo de Haliaeetus leucocephalus en el Norte de California J. Mark Jenkins and Ronald E. Jackman The Condor , Vol. 108, No. 3 (Aug., 2006) , pp. 730-735 Published by: University of California Press on behalf of the Cooper Ornithological Society Article Stable URL: http://www.jstor.org/stable/4151094
Did you know? Scientists discover the genetic reason why birds don’t have penises

http://www.smithsonianmag.com/science-nature/scientists-discover-the-genetic-reason-why-birds-dont-have-penises-94130874/

Note: This is a pretty frank discussion that includes a video.

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Male and female eagles are known to fly high, lock talons and tumble and cartwheel downward before releasing – sometimes just an eye-blink from hitting the ground. In rare cases, this foreplay winds down into a true death spiral. ... The eagles, which can live longer than 20 years, usually mate for life unless a mate dies.Apr 18, 2010

"Bald eagles lock talons and tumble into a 'death spiral' for two very distinct reasons. Courtship or territorial fighting," Lori Naumann, of the DNR's nongame wildlife program, told BMTN. "Either objective can end badly for at least one of the birds," she said.Oct 24, 2019

While courtship displays take place in flight, eagles do not mate in the air. Rather, copulation occurs on a branch or in the nest with the male mounting the female. During copulation, the cloaca of the male and female touch and sperm is transferred from the male to the female in what is known as the cloacal kiss.

When it comes time for the female Eagle to choose her mate, she prepares herself for many suitors. And many come before her. She looks them over quite well and then picks one to fly with for awhile. If she likes the way he flies she finds a small stick, picks it up and flies high with it.

But bald eagles don't usually suffer from brood parasitism, so they have no defenses to weed them out. “There's no reason that bald eagles should have evolved to recognize their own babies,” said Riehl, “because 999 times out of a 1,000, what's in a bald eagle nest is a baby bald eagle.”Jun 29, 2017

Typically, yes, although occasionally an intruding adult (not one of the pair) comes in (usually a female) and battles the resident bird for the territory, sometimes then taking over. If one of the pair dies, the other will find a new mate and usually keep going in the same territory.

Bald eagles stay hitched until death do they part, often returning year after year to the same nest. While there, the pair continuously adds to the structure, so that after many seasons it assumes gargantuan proportions and stands as a symbol of their fidelity.May 10, 2011

A. As with any birds where the genders have non-distinct plumages, the only ways to tell differences in sex are through size dimorphism (size differences) or in internal examination called a laparoscopy . Bald eagles exhibit size dimorphism; females on the average about 1/3 larger than males.

The Bald Eagle can also survive fasting for several days or even weeks. A courtship ritual, known as the death spiral, can be thrilling to witness. The pair lock talons in mid-air and then cartwheel downward, separating just before reaching the ground.Feb 2, 2019

Albatrosses. Another famously monogamous bird is the albatross. These birds spend much of their lives out at sea, safe in the knowledge that they have a faithful, dedicated mate for life when breeding season comes around each year.

History has it that the eagle has the sharpest vision of all birds. When its eyesight grows dull with age it glides up towards the sun, and, by staring at the sun, which only it can do, it burns away all the mistiness of age. ... Eagles fly high alone at great altitude and not with any other small birds.Jan 28, 2016

'The courtship involved a male and female eagle flying high in the air, where they grasp talons then glide in a dramatic fashion back down. 'They then break apart and do it again, then they chase one another. 'Afterwards they go back to their nest to mate.Jan 27, 2016

The father eagle "grabs the baby with his feet, drags it to the edge of the nest, holds it down and uses his beak to tear it to shreds," Strutton said. ... The next day, the father returned to the nest, again without food, and attacked the remaining chick the same way.May 19, 2002

Mating with second cousins or distant relatives may be common, particularly in small populations, but close inbreeding – the mating of full siblings or parents with offspring – has been rarely documented.Feb 16, 2015

Yes, baby bald eagles can kill each other. Newly hatched nestlings can be very aggressive to each other. They appear to be aggressive by nature. They may engage in fierce fights and hurt each other or terminate the fight and grow together (See video).

Eagles reproduce by engaging in a courtship process that includes cartwheeling and circling in the air, copulation and nesting, where both the male and female eagle build the nest. Eagles typically mate for life, and they usually use the same nest site year after year as long as they have successfully produced...

Bald eagles typically mate for life, except in the event of their partner's death or impotency-a number far lower than America's divorce rate, which now exceeds 50 percent. "Bald eagles stay hitched until death do they part, often returning year after year to the same nest," Carolyn Shea wrote in Audubon .

Nests are often re-used year after year, with additions to the nests made annually. Nests are often 4 to 6 feet wide and may weigh up to 1,000 pounds. Although bald eagles may range over great distances, they usually return to nest within 125 miles of where they were raised.

The Mating Dance. Bald eagles reach sexual maturity between 4 and 5 years old, at which time they become primarily preoccupied with finding a mate. During mating season, bald eagles engage in impressive aerial displays where they soar to great heights and lock talons, cartwheeling toward the earth while joined together.