Bald eagles rule the North American skies with amazing eyesight. In fact, their vision is four to eight times stronger than the average human being's.
Part of what makes bald eagles look so fierce is that their eyes are fixed in their sockets. They have to move their whole heads to look in different directions. When they do this, they can see far distances in great detail.
Bald eagles are also physically unique because of their strong, sharp talons. They use these talons to grip slippery fish, which is their main food source. Additionally, the soles of their toes are covered by special projections called spicules. Spicules—combined with talons—help bald eagles hunt.
In addition, bald eagles have pointed beaks. They use their beaks to tear the flesh of their prey. The upper part of these birds' beaks is sharp enough to slice through rough, tough skin just like scissors. What makes these beaks extra special is that they grow continuously throughout the eagle's life because they are made of keratin. This is the same substance that makes up human hair and fingernails.
Unlike many species, female bald eagles are actually larger than males. This is a concept known as reversed sexual dimorphism. Because the female looks after the young, she has to be able to defend herself against aggressive males. Females can even be 30 percent heavier than their mates.
Unfortunately, pesticides like DDT and hunting—particularly in Alaska—have decreased the bald eagle's population in recent decades. Since the 1990s, however, bald eagles have been recovering in number. Hopefully, this spectacular species' population will continue to mend in the coming years.
[Source: North American Birds]