Know Your Eagles: Quiz 2

Question #1: Can eagles sweat?

Mom panting
Sorry! The correct answer is 'No'. Eagles do not have sweat glands and so cannot sweat to cool themselves. Like dogs, they pant! We often see the eagles panting on warm days, especially before the nest tree grows a shady canopy of leaves overhead.

Question #2: How do bald eagles cope with cold weather?

Fort St. Vrain Nest
Sorry! The correct answer is #3: Eagles become less active, seek protection from the elements, and shiver. While activity can cause muscles to become warm, it also consumes much-needed energy. Micro-climates - think about the needled branches of a pine tree, or a pocket in a limestone bluff - provide some protection from wind and help eagles retain body warmth that would otherwise be lost to open sky. Panting loses heat, but shivering efficiently produces heat at up to five times an eagle's normal rate of heat production. We've seen eagles bring furry prey in, but they do not use the pelts. While some eagles migrate - bald eagles are partial migrants - not all eagles migrate and they don't fly specifically to NE Florida. The eagles that nest there in November and December are residents. To learn more about how eagles maximize energy gain and minimize energy loss, read this blog: https://raptorresource.blogspot.com/2015/02/how-do-eagles-stay-warm.html

Question #3: From hatch to fledge, how many days does a bald eaglet spend in its natal nest?

Eaglet To Fledgling
Sorry! The correct answer is 'About 80 days'. Bald eagles spend 75 to 80 days in their natal nest. Roughly the first 40 days are spent growing tissue and body features. The second 40 are spent growing flight feathers and developing strength and skills important to a fledgling eagle, including perching, self-feeding, prey preparation, and stealing and mantling food!

Question #4: Eagles have tiny projections on the underside of their toes that aid in catching prey. What are the projections called?

More than one part of an eagles feet helps to catch and hold prey.
Sorry! The correct answer is 'Spicules'! Talons and a Hallux Claw aid in catching and holding prey, but they aren't spicules.

Question #5: Who is who? Identify Mom and Dad Decorah!

Who is who?
Dad is incubating eggs and Mom is standing! Both male and female eagles incubate eggs, although female eagles spend more time incubating eggs than males do. ID can be tricky under IR light, but Mom's deeper brow is clearly visible in this photo.

Question #6: Who is who? Identify Mom and Dad Decorah!

Who is who?
Dad is on the left and Mom is on the right! While size can be deceptive on camera, this Valentine's greeting clearly shows the difference between the two. Female birds of prey are roughly a third larger than male birds of prey.

Question #7: True or false: Raptor hearts are markedly larger than those of similarly-sized mammals.

1905 illustration of bird anatomy
Sorry, the answer is true! In Ornithology, Frank Gill states that the avian (bird) hearts are about 41% larger than those of similarly-sized mammals. Avian hearts can jump from about 120 beats per minute to 300 beats per minute during periods of sudden excitement. Think about that the next time you see an eagle warning intruders away!

Question #8: What is the protrusion on the tip of a newly hatched eaglet’s beak called?

Mom and D24
Sorry, the answer is egg tooth! The egg tooth helps an eagle cut through its shell as it hatches. The sharp protrusion wears away in about three to four weeks.

Question #9: How many eyelids do bald eagles have?

Dad's eye!
Sorry! Like all birds of prey, eagles have three eyelids - a top eyelid, a bottom eyelid, and a transparent nictitating membrane. The nictitating membrane sweeps from side to side. It allows eagles to keep their eyes clean and moist without losing sight of their surroundings.

Question #10: How many degrees can a bald eagle turn its head?

Who is who?
Sorry, the answer is 270 degrees! 14 cervical vertebrae - seven more than humans have! - make for a very flexible neck. Eagles cannot roll their eyes, but they sure can rotate their heads!

Question #11: How wide is a bald eagle’s wingspan?

Sorry, the answer is 5.9 – 7.5 feet / 1.79 - 2.2 meters. Female eagles are bigger than male eagles and have greater wingspans.

Question #12: What is the rear talon on a bald eagle’s foot called?

Four toes
Sorry! The rear talon is called the hallux claw. The hallux claw helps bald eagles catch, kill, and carry prey.