What is "pintails"

Usage examples of "pintails".

He even went shooting, for numerous birds had been introduced into the crypt -- pintails, snipes, ducks, who fed on the fish which swarmed in the deep waters.

You could see pintails, teal, widgeon, both males and females in winter plumage, and there were wild ducks that I had never seen with plumage as delicate and complicated as our wood ducks.