You may have fed a few ducks in your lifetime, and maybe even seen a couple of ducklings waddling around—but how much do you really know about these birds?

1. Cold temperatures don't register.

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Their webbed feet have no nerves or blood vessels, rendering them incapable of feeling the cold. Which is an important adaptation when you consider that ducks can be found on every continent except for the inhospitable Antarctica.

2. Drakes aren't always fly.

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After a male duck, or drake's, chosen mate is hatching eggs, the birds undergo molting, temporarily losing their bright plumage, as well as their ability to fly. 

3. Preening helps them stay dry.

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Preening is the process by which ducks groom themselves—getting rid of dust, dirt, and parasites from their feathers, while also helping to waterproof their outer layer. During preening, ducks spread a waxy, waterproof oil secreted by their uropygial gland, which is located near their tails. 

4. The amount of daylight affects how many eggs a hen produces.

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The more daylight there is, the more eggs a hen produces. Farmers who raise ducks will often turn to artificial lighting in order to give their hens about 17 hours of light a day

5. Some ducks have expensive taste. 

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The omnivorous birds also tend to consume gravel, small stones, or sand—not for the nutritional value, but so they can store the substances in their gizzards and use the rough textures to break down food. In 1911, according to Ducks.org, gold prospectors flocked to Nebraska after hunters discovered small nuggets of the precious metal in the gizzards of ducks they had shot. However, the fortune-seekers never were able to locate where the gold originally came from. 

6. Ducks have excellent vision.

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Because a duck's eyes are located on either sides of its head, they have a field of vision of nearly 340 degrees. And thanks to the shape of their eyes, they can see objects both near and far simultaneously. To top it off, ducks have three eyelids and can see in color.

7. Mass migrations can cause mass chaos.

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Very rarely, a severe weather event will trigger a mass migration known as a “grand passage.” There have been only three recorded instances of grand passages: one in 1940, one in 1955, and the most recent in 1995, when a reported 90 million waterfowl migrated from Canada after a severe cold front set in, causing major problems at airports along the birds' route. 

8. Good luck trying to sneak up on one.

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Ducks are incredibly vigilant creatures. According to a study done by scientists at Indiana State University, Mallard ducks stay alert even when they doze. While snoozing in groups, the ducks stationed as "guards" on the outside sleep with one eye—generally the eye facing away from the group—open. In doing so, they control which side of the brain stays awake. It's not surprising, then, that ducks are capable of sensing threats in the environment in under a second.

9. Ducklings grow up fast.

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Unlike the young of many other animals, ducklings achieve independence almost immediately after hatching. Babies are born with their eyes wide open, and already possess the layer of down feathers necessary to stay warm. By the time they're two months old, ducklings have usually learned to fly.

10. One myth about them has been debunked (many times over). 

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Despite stories to the contrary, a duck's quack does indeed echo.