Not quite, they're domestic ducks that are raised for meat, eggs and down.
Many ducks are also kept for show, as pets, or for their ornamental value.
Almost all varieties of domestic duck apart from the Muscovy duck (Cairina moschata) are descended from the mallard (Anas platyrhynchos)

Idk, it's always been there

It was the wrong lever!!
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It always is the wrong lever...

Ö̷̲̮̜̦͖̆̄̆̀̏̍͌͒K̶̺̯̟̤̀̓̉̿̿̓͘͜!̶̨̤̥͚̫̥̆̌̔͋̒̒̄͘͘͝!̸̲̦̎́̈́̆͊͠

and desist?

:3

Yes! That poison.

Yup

Origins:
A tale recounts how a woman had washed only half of her children when God came to her cottage; ashamed of the dirty ones, she hid them. God decreed that those she had hidden from him would be hidden from humanity; they became the hulders.

The hulder is one of several rå (keeper, warden), including the aquatic sjörå or havsfru, later identified with a mermaid, and the bergsrå in caves and mines who made life tough for the poor miners.
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More information can be found in the collected Norwegian folktales of Peter Christen Asbjørnsen and Jørgen Moe.
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The hulders were held to be kind to charcoal burners, watching their charcoal kilns while they rested. Knowing that she would wake them if there were any problems, they were able to sleep, and in exchange they left provisions for her in a special place. A tale from Närke illustrates further how kind a hulder could be, especially if treated with respect (Hellström 1985:15).