Four things people
get wrong about ducks.
In rising order of how much better the true version is.
Myths, and what's actually going on
Myth 1
“A duck's quack doesn't echo.”
It is repeated confidently and constantly, usually with the implication that nobody knows why.
It echoes perfectly well. Trevor Cox at the University of Salford put a duck called Daisy in an anechoic chamber and then a reverberation chamber in 2003 and recorded the echo. It is hard to hear because a quack fades out gradually, so the echo arrives underneath the tail of the original sound instead of after it.
Myth 2
“Ducks quack.”
Some do. The one on the soundtrack of every cartoon is a female mallard, and she is doing the work for the whole family.
Of roughly 170 species in the duck family, most whistle, grunt, coo, bark or hiss. Male mallards rasp. Muscovies hiss. Whistling ducks are named for the noise they make. Quacking is close to a mallard speciality, and mostly a female one.
Myth 3
“Bread is fine, it's what everyone feeds them.”
It is certainly what everyone feeds them.
Bread fills a duck up without feeding it, and the uneaten half rots in the water, feeds algae and draws rats. A high-carbohydrate diet is also linked to angel wing, a deformity that leaves a bird unable to fly. Oats, peas, sweetcorn, rice and chopped lettuce all work and are no more expensive.
Myth 4
“Their feet must be freezing.”
A duck standing on ice at dawn looks like it is having the worst morning of any animal present.
The legs run a countercurrent heat exchanger: arteries carrying warm blood down are bundled against veins carrying cold blood up, so the heat is handed over and turned back before it reaches the foot. The foot is then kept only just above freezing — and with little muscle or soft tissue down there, there isn't much to damage.
The feet, in detail
Barely any heat reaches the bottom of the leg, so barely any is lost to the ice — and with little muscle or soft tissue in the foot, there is not much down there to damage. The same trick, countercurrent exchange, turns up in fish gills, in a penguin's flipper and in the plumbing of a well-designed heat-recovery system. Ducks got there first.
How big is a duck
Typical adult body length, bill tip to tail tip. A cropped photograph tells you nothing about this, which is why the flock page looks so misleading.
Wingspans run roughly double these numbers, and a northern pintail owes a quarter of its length to two tail feathers.
And the one about programmers
Rubber duck debugging
You keep a rubber duck on the desk. When the code won't work, you explain the code to the duck, line by line, out loud. Somewhere around the third sentence you hear the wrong thing come out of your own mouth and the bug is found. The duck has done nothing. The duck is essential.
Named in The Pragmatic Programmer (1999), and the reason a startling number of engineers own a duck.
The quack is a real recording — one duck, 0.18 seconds of it, lifted out of a three-second file that is otherwise silence. It is embedded in the page as data and decoded through Web Audio, so clicking the duck sends no request to anyone, including to this server. Credited in full on the credits page.