Curiosity killed the cat. I never heard exactly how. But The History of Borough Fen Decoy, written by Tony Cook & R.E.M. Pilcher, explains how curiosity killed a lot of ducks. With the help of some dogs.
A decoy, in this sense, is not a fake duck meant to encourage real ducks to fly down and join it. It's a carefully designed pond with curved arms, meant to encourage ducks to hang out there in large numbers – and occasionally get netted at the end of an arm, also in large numbers. In the 1804-5 season they trapped “450 dozen and 8” ducks at Borough Fen Decoy. They sent those 5,408 ducks to be sold in London. You could make a lot of money with a decoy, and there were hundreds in England and Ireland, in suitable areas, such as the Fens.
(After Anne Treadwell-Cook, in Cook & Pilcher.)
They seem to have been invented in the Netherlands, and brought to the UK by the enterprising Sir W. Wodehouse, who lived in the early 1600s. (Surely a relative of the brilliant P.G. Wodehouse.) “Decoy” is an Anglicisation of “Eend-kooi,” which means “duck-trap.” Knowledgeable types, decoymen, would just call it a coy. Or kooi, if they were knowledgeable Dutch types.
The arms, or “pipes,” of the decoy are covered with high archways of local reeds, a pleasantly rustic effect. The banks are gently sloped, perfect for resting on while you doze or rearrange your plumage, if you are a duck. At the end it is a giant tunnel-net. There are reed screens along one side of the pipe, so you can sneak along without being seen by the ducks, if you are a decoyman. The screens have gaps between them, and are fanned, so “The final effect is that of a Venetian blind laid half-open on its side”.
(Ineptly, after Anne Treadwell-Cook, in Cook & Pilcher.)
The pond is shallow, so as not to encourage diving ducks, which can get away too easily and which are considered inferior eating. It is kept clear of reeds, to discourage ducks from skulking there, and its banks are steep and uncomfortable.
The simplest way to catch ducks in a decoy is to notice that there are a bunch of ducks relaxing in one of the pipes, probably because you laid out a nice duck-food buffet there the night before. (You selected the pipe in accordance with the wind direction, since ducks don't like to take off with the wind behind them.) You suddenly pop out from behind a screen near the mouth of the pipe, the horrified ducks flee down the pipe, you bound along and pop out at the next gap, chasing them, and they fly into the net or “bunch huddled together,” at the end. A twist of the net traps them all. Because of the Venetian blind effect, ducks in the pipe could see you, but ducks in the pond could not.
But often the ducks don't go far enough into the pipes to make this a fruitful endeavor, even though food is there. This is where the dog comes in. Instead of scaring ducks further down the pipe with the sight of your ghastly self, you entice them into the pipe by giving them glimpses of the dog. You send the dog over a low “dog-jump” between screens, and it runs down the bank of the pipe and disappears over the jump behind the next screen.
Wak? What was that? The ducks swim a little further down the pipe, stretching their necks to see what's going on. Wak?
Meanwhile you sneak behind the screen and signal the dog to go over the next jump at the right moment. The ducks pursue. Wak! Wak! Did you see that?
Wak! I saw it again! Hurry! Wak wak wak!
When the ducks are far enough down the pipe, you show your scary self, the ducks panic and rush down the pipe, and are netted as before.
Why do the ducks follow the dog? One explanation is that they are curious. They want to know more. Animals generally want to know what is going on in their world. Plains Indians used to lure pronghorns within arrowshot by lying in tall grass and waving a stick with a cloth on it. The antelope just had to find out what that thing was.
And if there's a predator sneaking around it would be nice to know what kind of predator it is and where and what it's doing. Traditionally decoy dogs are supposed to look like foxes – small, ginger-coated, bushy-tailed dogs. (Tradition has been flouted by the use of yellow labs, white terriers, and “a large Newfoundland-type” dog. Also a cat. Sir Ralph Payne-Gallwey experimented with a rabbit, a ferret, and a monkey he borrowed from an organ-grinder. But you should use a small ginger dog and you should name it Piper.)
More than curiosity, the ducks may feel the urge to mob the probable predator. When animals mob a predator, they surround it in a crowd, make as much noise as they can, and maybe peck at it. This might seem risky, but it's common. If you hear a tremendous shrieking of birds in the forest, you may find a cloud of small birds mobbing a hawk or an owl. The hawk or owl is made miserable and knows it has no chance of taking any prey creature by surprise, so it flies off, pursued by shrieks. At my sister's farm the guinea fowl have been heard and seen mobbing a bobcat and a coyote, each of which ran away. So the ducks in the decoy may be planning to catch up with that dog or fox or whatever it is (that can't be a monkey? – wak!) and hassle it. They would wave pitchforks if they could.
Most decoys are long gone. Borough Fen hasn't been used to catch ducks for sale since the early 1950s. The Wildfowl Trust, under famous ornithologist Sir Peter Scott, turned it into a bird-ringing station. Ducks are caught, banded, and released, in the pursuit of knowledge about their migrations. Cook and Pilcher proudly write “There is one recovery of a Teal from Turkey.”
The decoy doesn't work as well when ornithologists run it. The trouble is that banded ducks remember. They hang about near the mouth of the pipe making worried noises. They won't go in, and other ducks, “sensing the disquiet of their experienced fellows,” also become unenthusiastic. Major criminals have a rule: Leave No Witnesses. This is probably why we don't know what happened to that cat.