17th January: Bald Eagle Appreciation Day

For Bald Eagle Appreciation Day, 10 facts about bald eagles:

1. You've probably seen a picture of one, and they are obviously not bald, so why are they called "bald eagles"? The word "bald" in this case derives from "piebald", referring to their white heads and tail feathers. The scientific name, Haliaeetus leucocephalus, translates as "white-headed sea eagle".
2. Their favourite food is fish, including fish which have been stunned or killed by water turbines and Salmon which have died off after breeding. They are opportunistic predators, though, and will also prey on small birds and mammals.
3. Their nests are the largest tree nests of any animal. They can measure up to 4 m (13 ft) deep, 2.5 m (8.2 ft) wide and weigh one metric ton.
4. Females are 25% larger than males. The plumage of the two sexes is the same.
5. A bald eagle can fly at 70km per hour (43 mph) and can reach speeds of 160km per hour (99mph) when diving.
6. The bird is sacred to Native American cultures, some of whom believe that they are messengers from the gods to humans.
7. According to US law, only people of certifiable Native American Ancestry who are members of a federally recognised tribe are allowed to possess bald eagle feathers for use in religious ceremonies. Their supplies come from The National Eagle Repository, which collects and stores eagles which are found dead, and distributes the feathers and any other parts required, to approved people.
8. They don't have vocal chords. They do make sounds, but the screaming sounds eagles make in films are actually made by red-tailed hawks and are added more for dramatic effect than authenticity!
9. Most people know that the bald eagle is the national bird of the USA. It features on the Great Seal of the United States, holding 13 arrows and a 13-leaf olive branch with its talons. On the seal, the eagle is shown looking towards the Olive branch, but in some 20th century versions of the presidential flag show it looking in the other direction, at the arrows. This has led to an urban myth that the flag changes to have the bird looking at the arrows whenever the country is at war.
10. Another urban myth is that Benjamin Franklin suggested that the US national bird should be the Turkey. There's no evidence for this, although there is written evidence that he wasn't keen on the bald eagle - he thought they were cowardly birds of bad character!