When purchasing ducklings, one of the first questions that comes up is "Are they boys or girls?". Telling the sex of a newly hatched duckling can be difficult. Here are common methods used to determine the sex of a duckling.
Vent Sexing: This is basically checking the sexual organs of the duckling. It sounds easier than it actually is since the organs for both boys and girls are INSIDE the duck's vent.
BYC member Ace_king_brahma posted these instructions for vent sexing.
"Step 1: Hold the bird upside down. Hold the gosling or duckling with its feet against its belly. Use your index finger to gently press about 1/2 an inch below the vent with your knuckle. The bird might poop at this point just wipe it off and apply pressure again.
Step 2: With your other hand gently tuck the tail toward the bird's back. Gently place your index and thumb at either side of the vent. Gently pinch them together. You only want to push the vent lips together and you will feel them flexing against your fingertips. Hold it like this for a few seconds and then gently push your fingers open and press down with gentle pressure to make the cloaca invert.
Step 3: If the vent doesn't fully invert gently keep applying pressure until it does. At this point if you have a male his penis should be exposed. It will be either white, pink or even dark grey to almost black depending on breed. It should pop out a little if not it should after a second or two. Females are sometimes hard to sex but should be just red to pink lips with no corkscrew like tip hanging out. Some males will hold it in and can be mistaken for a female. You can always sex them again later when they get a bit bigger. Never keep them inverted more than a few seconds. I can't recall how long but I would safely say 20 seconds max.
Step 4: Release pressure on belly and vent. Gently rub the vent if everything doesn't tuck back after releasing pressure. Rubbing should help gently push the vent back in place."
Vent sexing is usually the method used by hatcheries when you order sexed ducklings.
WARNING! Done incorrectly this can seriously harm your duckling. Either leave this to the pros or try to have an experienced person show you how to do this.
Voice Sexing: The quack noise usually associated with ducks ONLY comes from the females. Males make a very monotone, deep, raspy peep noise even though both males and females start out sounding the same. As the duck matures, the voice changes.
Females can start quacking as soon as 2 weeks after hatching, but it is more likely going to take 4-6 weeks before you hear the females make a quack noise. As it was rather humorously described by another BYC member, the female quack can also sound more like the cross between "a cough and a fart" instead of an outright quack. The key is tonal range and volume. Girls will make a wide variety of noises and will get louder with time.
Boys voices will change from typical duckling peeping noises to a more monotone peeping. Eventually, usually by 8 weeks, they will be very monotone and much quieter than females only making a raspy noise. In the case of muscovy ducks, males will hiss.
Go to this site to hear sound files of the different noises made by male and female ducks.
In this short video, the grunting "whoopie cushion" noises are coming from the young female khaki campbell mix duck (rich brown colored). The peeping is from the younger male rouen.
Plumage Sexing: Many ducks have different feathering on males and females. Mallards are a prime example with males having shiny green heads, a white neck ring, brown chest, etc... while the females are a more uniform dull brown. This is fine for telling adults apart, but not very helpful for ducklings. Many ducklings go through a developmental phase where they all look like females. It isn't until they are 3 months or more that you will begin to see signs of adult feathering.
One sign is the "drake feather". On male ducks, one or two of their tail feathers will curl up while the feathers on a female's tail will remain flat. The drake feather may not appear for 2-3 months. If the duck is molting, it is also possible to not see a drake feather until new feathers grow in.
Beginning signs of a drake feather on a 7 week old rouen male.
Same duck a few weeks later with obvious drake feather. This also shows other changes like the feathers on the back and underneath. They have changed from the feather pattern common to females to a drake feather pattern.
Mature drake (furthest right) with noticeable drake feathers. Note the two females in the photo both have smooth tails.
In the case of Peking ducks, both males and females are solid white. There is no plumage difference to help you tell them apart and other means must be used.
Size: In the case of muscovy ducks, males get much larger than females, though this size difference will not appear until the ducklings are several weeks old. Males will also develop a larger red "mask", but this also takes time.
Other methods: There are some breeds that have subtle ways to tell apart the males in females. In the case of Welsh Harlequins, "a darker bills means a male and lighter bills ending in a dark spot are normally females. Within several days this distinction disappears." - Metzer Farms
With muscovy ducks, even before a size difference between males and females becomes visible, boys often have large feet and bigger claws.
With Khaki Campbell ducks, a dark Khaki hen bred to a regular Khaki Campbell drake will result in sex-linked offspring.
Regardless of which method you use to try and sex your ducks, one thing is certain. If it lays and egg, it is a girl
Edited by Wifezilla - 6/29/09 at 2:29pm