I do not know about a "crate" of ducks, but a group of many ducks is called a gather I think. Check out a few more answers too.
Water fowl.
Ducks are often called "water fowl" or "game". quackers
yes the webfoots
A box of quackers
Dogs may go into another dog's crate out of curiosity, seeking comfort, or to establish dominance.
Another name for a owl's beak is called a bill or rostrum.
ACME.
Cage, Crate
The Anahiem Ducks were formed in 1993 under the name "The Mighty Ducks of Anaheim".
They rubb their heads on other male or female ducks (depending on bi or straight)
Originally called the Webfoots for the consistant moistness in the Willamette Valley, the name was shortened to the Ducks in relation to the original team name.
Yes but they will be under your chickens not the ducks.