Many bird species are sexually monomorphic, meaning males and females look identical. DNA sexing provides a fast, accurate, and non-invasive way to determine sex without relying on physical traits.

DNA testing is over 99% accurate when performed correctly. It identifies a bird’s sex by detecting differences in genes found on the sex chromosomes.

Many bird species can be sexed using this method. The most common approach (based on the CHD1 gene) works for a wide range of species, and we also provide a few alternatives for cases where CHD1 test may not be suitable.

To find out if your bird species is supported, check our searchable guide:
Choosing a DNA Primer Set for Bird Sexing

If your species isn’t listed, or you’re unsure, feel welcome to get in touch with us — we’re happy to offer advice.

Feathers, blood, or eggshell can all be used for DNA sexing. Feathers are generally the least stressful and easiest to collect, making them a popular choice.

• Feathers (pulled, not shed)
• A small drop of blood (from a clipped nail or vein)
• Eggshell fragments (from recently hatched eggs)

For feathers, gently pluck 2-3 from the chest or underwing. For blood, a tiny drop from a clipped nail is enough. Always follow ethical handling guidelines to minimize stress.

We recommend getting our Bird Sexing Bundle and Bento Lab, which will equip you with almost everything you need, apart from a few standard items like water, gloves and paper towel.

All the reagents, consumables and equipment you need in order to follow the DNA Extraction from Feathers and Bird Sexing Protocol are listed below.

Once you have equipment, the cost can be as low as $2 USD per sample for the materials – depending on which materials you use, and if you’re processing multiple samples at once. We would suggest starting small, and estimating about $5 USD for materials per sample at the very start.

We have put together a spreadsheet calculator if you want to calculate how the costs change with different quantities of samples.

If you have any questions or feedback about the spreadsheet, please get in touch. We are happy to discuss costs via email.

You can learn to do it yourself without training.

Bird DNA sexing is a reasonably complex process that involves careful sample collection, DNA extraction, PCR, and gel electrophoresis. If you’re new to molecular biology techniques, some steps can be tricky at first, but many people have successfully learned to do it themselves.

Our resources are designed to be as beginner-friendly as possible, and many users get great results by following them independently. If you get stuck, we’re happy to help by email.

If you prefer hands-on guidance or want to build confidence with expert support, our optional training course walks you through the entire workflow step-by-step, making the learning process smoother and more accessible.

Birds have two sex chromosomes known as Z and W. These are similar to the X and Y sex chromosomes in humans – each inherited from one parent. Male birds have two copies of the Z chromosome (ZZ) and females have one copy of the Z chromosome and one copy of the W chromosome (ZW). This is the opposite of the situation to humans, where most biological females have two copies of the X chromosome (XX) and most biological males have an X and a Y chromosome (XY).

This PCR workflow involves the CHD1 (Chromodomain Helicase DNA Binding Protein 1) genes, which are present on the W and Z sex chromosomes of birds as two variants – CHD1-W (on the female-specific W chromosome) and CHD1-Z (present in males and females on the Z chromosome). These genes are homologous (almost identical in structure and function) but contain introns (DNA that is removed by RNA splicing before it is translated into mature RNA) that usually differ in length between sexes within a species and between species.

This difference in length allows both sexes to be determined using a simple assay based on intron length differences. Once DNA has been extracted, regions within the CHD1-Z and CHD1-W (if present) genes can be amplified using the polymerase chain reaction (PCR), and the amplified DNA visualised on an electrophoresis gel. If only one band is present, this suggests that only one CHD1 coding variant is present (CHD1-Z), which would be expected for a male with a ZZ chromosome pair. If two bands are present, this suggests that both CHD1-Z and CHD1-W genes are present, which would be expected for a female with a ZW chromosome pair.

The advantage of amplifying both variants (if present) together is that the band produced by the CHD1-Z should always be visible – it will only be absent if the DNA extraction or PCR fails. It therefore acts as an individual positive control for each specimen.