Episode 61 – Golden Eagle: The Aquila and the Bleat

“…And today we are talking about a bird with an impressive wingspan and brutal hunting tactics. I would make a joke, but frankly, I’m scared of it.”

A bird who’s at home in the skies needs a body built for aviation. That means a light frame, hollow bones, and a wingspan wide enough to generate lift. But when a delicate bird of flight is also a bird of prey, those slight features need to be augmented by an arsenal of deadly weapons. Even the largest raptors could use inventive tactics in order to take down large targets. But you know what they say, the bold and unorthodox bird gets the worm, especially when that worm is more than twice your size, in Life, Death, and Taxonomy.

Measure Up

Wingspan – 1.8 to 2.34 metres (5 ft 11 in to 7 ft 8 in) – How many golden eagle wingspans go into length of the Alaska-Yukon border (1,210 km (752 mi))? Hint – The Yukon has average winter temperatures that are mild by arctic standards, between 12 and -29 in January depending on the region. However, they also see the coldest temps in North America during cold snaps hitting -76 degrees F three times. Answer: 451,200 Eagles

Female weight – 3.25 kg (7.2 lb) – How many Golden Eagles go into the gross vehicle weight of a 2018 Jeep Wrangler JK Golden Eagle 4×4 (4900 lbs)? Hint: The Golden Eagle Jeep is considered an off-road legend but it’s as comfortable on the road as an actual eagle is walking along the ground. Answer: 680.5 eagles

Major Fact

Golden Eagles are prolific hunters that pray on a wide variety of animals throughout the year.

  • The type of animals they hunt depend on the season and what’s abundant at the time.
  • They live in a wide variety of environments but prefer to avoid dense forest and developed areas.
  • Plains, tundras, mountains, and hills are ideal.
  • They will often hunt by flying high to spot prey and then dropping down and flying close to hills and cliffs to conceal their large frames.
  • They usually stay under 50 feet of altitude when going for a kill because this usually puts them below the horizon line to animals that are within their angle of approach.
  • This allows them to blend into the earth tones instead of contrasting against the monochromatic blue or grey sky.
  • Their preferred method of hunting is to drop onto their prey, dig in their talons, and hold on until the job is done.
  • In smaller animals, the grip can crush bones but they typically attempt to pierce vital organs.
  • It can take anywhere between a few seconds and 15 minutes to make a kill after the initial impact.
  • If you were a rabbit that was attacked by a golden eagle, you might be going about your day eating grasses and sages until you hear a thunderclap a few fractions of a second before a big staby bird slams into you.
  • This thunder sound is actually the sound of the eagles wings and tail feathers popping open and whipping against the wind to help control the impact.
  • Diving eagles will tuck their wings in, allowing them to reach speeds close to 200 mph, challenging the peregrine falcon for fastest animal on earth.
  • They typically hunt and eat birds, leporids (bunnies), rodents, reptiles, amphibians, and ungulates.

That’s right, ungulates like sheep, pigs, deer, and goats. Animals that typically more than double the weight of an eagle.

  • The majority of ungulate kills are newborns and smaller individuals.
  • The average weight of kills are 5 to 11 pounds, which is close to the weight of an eagle.
  • However, in the fall and winter, animals born in spring and summer will have started to pack on the pounds.
  • They have been observed attacking larger adults when there are no other food sources around, with pray over 40 pounds.
  • They have even been observed killing adult pronghorns, which can be as heavy as 70 pounds.
  • One way eagles take down larger prey like mountain goats and ibex, is by letting gravity do the work for them.
  • Eagles will swoop down, latch onto a goat, and try to force them off of a cliff to their deaths.
  • Sure footed mountain goats don’t easily lose their footing but they can be forced off with enough speed and momentum.
  • In some cases, they will latch onto a goat and drag it against rocks as it tumbles down a slope, letting go only when they come to a big drop.

Hunting larger prey can be dangerous for several reasons.

  • Though eagles typically select prey that they can easily outmatch, like sick, injured, or young animals, there are reports of hunts turning fatal for the hunter.
    • Does may trample eagles that are attempting to kill fawns.
    • There’s one report of an eagle fighting a great blue heron in an attack that left them both mortally wounded.
    • Eagles may also go after predators like wolverines that can injure or kill them.
  • Larger prey also mean that eagles can’t carry meals away, so other predators like bears, leopards, and wolves can come across their kill and challenge them for it.
  • One of the biggest natural threats to golden eagles is other golden eagles which are extremely territorial and do not readily share kills.

Outro

*thunder cracks*

Carlos: Relax, it’s only thunder!

Joe: Oh! I thought it was the foreboding wingbeat of a golden eagle in a predatory dive.

Carlos: Nope, just your typical hotter-than-the-sun lightning strike.

Joe: Well, good, that’s much less scary. Hey, you know what else is scary?

Carlos: What’s that?

Joe: How dangerously close we are to running out of Measure Up intros from our loyal listeners.

Carlos: Really? Even though it takes less than 30 seconds to record and send?

Joe: Yeah, even though all you have to do is speak, sing, or chitter into your phone’s messaging app, click the share icon, click email, and then email it to ldtaxonomy.com…

*eagle screech*

Joe: Was that also some very strange thunder?

Carlos: Not this time! We better get out of here.

Joe: Right behind you!