Method #1: Vent sexing

There is only one reliable way to sex young ducklings: vent sexing.

Vent sexing involves physically manipulating a duckling’s vent, or cloaca, to evert the sexual organs. If done right, it is, of course, accurate.

Here’s a video from Metzer Farms about how it’s done:

This is best done on day-old ducklings, but can be done on ducks of any age.

However, it’s not a good method for beginners. It’s easy to hurt the duckling if you’re not careful or not sure what you’re doing. Also, it’s easy to obtain an inconclusive result: if you see a penis, you have a male; if you don’t, you either have a female or you did it wrong.

If you want to learn vent sexing, ask someone experienced to show you how before attempting it yourself. Otherwise, I don’t recommend it.

Method #2: Bill and plumage color

You may have heard of autosexing chickens or geese, where male and female hatchlings can be identified by their down color. Unfortunately, there are no true autosexing ducks.

However, there is one breed where ducklings can (sometimes) be sexed by bill color: the Welsh Harlequin.

Female ducklings will have pinkish bills with a dark bean, while male ducklings will have dark bills.

Female Welsh Harlequin duckling with a light-colored bill. Photo used with permission from “shyBadger.”

Male Welsh Harlequin duckling with a dark bill. Photo used with permission from “shyBadger.”

By the time they’re about four days old, the females’ bills will have darkened and the difference will no longer be distinguishable.

Unfortunately, it’s not always reliable. In the 2000 edition of Storey’s Guide to Raising Ducks, Dave Holderread says he has found day-old bill sexing to be approximately 90% accurate. Furthermore, this trait is easily lost in breeding unless care is taken to preserve it, so in many lines, bill color sexing is difficult, unreliable, or impossible. I have seen some people say that it works well on high-quality bloodlines and not on hatchery stock, while other people say it works well on hatchery stock but not on show-quality birds.

Beyond the Welsh Harlequin, there are also a few crosses that will produce sex-links where males and females have differently-colored down upon hatching. Sex-linking differs from autosexing in that it is only the result of crossbreeding and won’t carry through to future generations, while autosexing is found in pure breeds.

Some examples:

• The Golden 300, Golden Layer, and Gold Star hybrid, sold by various hatcheries, are sex-linked crossbreeds where males are shades of black and females are shades of brown.
• Crossing a purebred Golden Cascade drake with any other duck will result in sex-linked ducklings where the males are dark brown and the females light brown. (If you see Golden Cascades for sale that are purported to be autosexing, that likely means that they have already been crossed with another breed. Some sources sell Golden Cascade crosses rather than pure Golden Cascades, which are not autosexing.)
• Crossing a Khaki Campbell drake with a black female duck (Cayuga, Swedish, etc.) will create a sex-linked crossbreed where, like above, the males are black and the females are brown.
• Crossing a Khaki Campbell drake with a Silver Welsh Harlequin also results in a similar sex-link.
• Crossing a Khaki Campbell drake with a Dark Khaki Campbell duck will produce khaki females and dark drakes.
• Crossing a Gold Welsh Harlequin drake with a Silver Welsh Harlequin duck will create sex-links where drakes are silver and ducks are gold.
• In Muscovies, the chocolate gene is sex-linked. A chocolate drake crossed with a black, blue, or self-blue duck will produce sex-linked ducklings of different colors.

These ducklings are a cross between a Khaki Campbell drake and a Silver Welsh Harlequin hen. The three males are very dark, nearly black, while the females are a lighter brown.

This is not an exhaustive list. There are many combinations that can create sex-linked offspring. Here are a few resources with more information:

• http://www.moosemanorfarms.com/whxblue.html
• http://domestic-waterfowl.co.uk/sexlinked.html
• https://www.waterfowl.org.uk/docs/SEX_LINKAGE_WATERFOWL.pdf

Method #3: Other clues?

It’s time to move on to juveniles and adults.

What? That’s the end of the duckling section?

Yes.

If vent sexing isn’t an option, and if you don’t have Welsh Harlequins or a sex-linked cross, you will be forced to wait. There are no effective, reliable ways to sex a duckling before they start quacking.

Yes, you might read or hear about some other methods. Here are methods for sexing ducklings that don’t work or are unreliable:

Method #1: Vent Sexing

Vent sexing works on adult ducks as well. It’s more difficult to do, but there is less risk of causing injury to the duck. However, again, it’s not recommended unless you know how to do it.

Method #2: Voice

Photo credit: “Aaaaaak!” (CC BY-NC-ND 2.0) by tifotter

The classic, archetypal “quack” sound is that of a female duck. Male ducks only make a hoarse, croaky, rasping sound.

Because the difference between male and female ducks’ quacks is so evident, voice sexing is often the best way to identify your duck’s sex. It’s fairly easy, reliable, and the difference shows up long before the ducks are fully mature, so you usually don’t have to wait very long.

Male and female ducklings sound the same at first, and after a few weeks, the females’ voices change and they start quacking. Males also transition to their adult voices after a few weeks, although they usually take longer than females. Females are also louder than males.

This page has good audio clips demonstrating male and female quacks: http://www.majesticwaterfowl.org/artquacks.htm

Here are two videos showing what a male duck’s “quack” sounds like:

And here are three videos showing female ducks quacking:

This video shows compares the quacks of both male and female Pekin ducks:

Method #3: Bill color

In this flock of Abacot Ranger ducks, notice how the males have yellowish bills and the females have dark gray bills. Photo used with permission from avicoliornamentali.it.

In a few breeds, male and female ducks have different bill colors. The difference is not apparent in ducklings, but usually becomes visible around 8 weeks of age, or anywhere from 6-9 weeks.

This is usually before plumage differences become apparent, so if you’re struggling with telling male and female voices apart and if you have one of the breeds that can be sexed by bill color, this trait can be quite handy.

However, be careful and don’t rely on bill color for sexing too much. It’s often an inconsistent trait, especially in some breeds and lines.

A male Buff Orpington with a yellow bill. Photo used with permission from The Domestic Waterfowl Club of Great Britain.

A female Buff Orpington with an orange-brown bill. Photo used with permission from The Domestic Waterfowl Club of Great Britain.

A Silver Bantam drake with a yellow-green bill. Photo used with permission from Vicky Quick.

A Silver Bantam duck with a slate gray bill. Photo used with permission from Vicky Quick.

A female Mallard with an orange bill and a male Mallard with a yellow bill.

A female Rouen with an orange bill and a male Rouen with a yellow bill. Photo used with permission from The Domestic Waterfowl Club of Great Britain.

A female duck with a speckled bill. Photo credit: “Duck!” (CC BY-NC-ND 2.0) by davespilbrow

In addition, bill speckles can be a clue. Due to hormones, laying female ducks often gain speckles on their bills. A duck with a freckled bill is often a female, while a duck without freckles could be either sex.

Method #4: Drake feather

Often, an easy way to spot a drake is the blatant signpost they carry on their tail: the drake feather, also called the drake curl or sex feather.

This tail feather is prominently curled and instantly identifies its owner as a drake. Some drakes have two or more drake feathers.

This drake has two easily-spotted drake curls.

Here, of course, comes the “but.” If it was always that easy, no one would doubt their duck’s sex.

There are three reasons a drake might be missing the drake feather:

Method #5: Plumage

This resplendent green head could only belong to a drake.

In many breeds of ducks, males and females have different colors and patterns. Males typically have brighter colors and flashier patterns, while females will have duller, less ostentatious plumage. For example, in some breeds, such as the Mallard shown above, males have iridescent green heads, while females have dull brown heads.

At first, when young ducks start gaining their feathers (their juvenile plumage), males and females look the same. However, around 12-16 weeks, males transition into their showy nuptial plumage.

While drakes are in their nuptial plumage, it’s easy to distinguish them from females. Unfortunately, after breeding season, in summer or early fall, drakes molt, swapping out their nuptial plumage for eclipse plumage, which looks a lot like a female’s plumage. They molt back into nuptial plumage in late winter or early spring, but for a good portion of the year, they look similar to females.

Here are some examples (see “Bill Color” for more picture examples):

A Saxony drake. Photo used with permission from The Domestic Waterfowl Club of Great Britain.

A Saxony duck. Photo used with permission from Michaela Knott.

A Silverhead Australian Spotted drake. Photo used with permission from Beau McLean of Duck Creek Farm.

A Silverhead Australian Spotted duck. Photo used with permission from Beau McLean of Duck Creek Farm.

A male Welsh Harlequin with a yellow-green bill. Photo credit: “Pretty Drake” (CC BY-NC 2.0) by April Shuyler

A female Welsh Harlequin with a dark gray bill. Photo credit: “Here’s Mama! She’s a layer too!” (CC BY-NC 2.0) by Steve Wedgwood

A Blue Butterscotch Call drake. Photo used with permission from Beau McLean of Duck Creek Farm.

A Blue Butterscotch Call duck. Photo used with permission from Beau McLean of Duck Creek Farm.

Here’s a list of duck breeds where males and females are colored differently (while in nuptial plumage):

• Abacot Ranger
• Alabio
• Australian Spotted
• Bali (some color variations)
• Blue Swedish
• Buff Orpington
• Call (some color variations)
• Crested (some color variations)
• Duclair
• Dutch Hookbill (some color variations)
• Indian Runner (some color variations)
• Khaki Campbell
• Mallard
• Rouen
• Rouen Clair
• Saxony
• Silver Appleyard
• Silver Appleyard Miniature
• Silver Bantam
• Welsh Harlequin

Here are the breeds where males and females look the same:

• Ancona
• Aylesbury
• Bali (some color variations)
• Call (some color variations)
• Cayuga
• Crested (some color variations)
• Dutch Hookbill (some color variations)
• East Indies
• Indian Runner (some color variations)
• Magpie
• Muscovy
• Pekin
• Shetland

Method #6: Behavior

Behavioral differences between male and female ducks show up once ducks reach sexual maturity.