Non-invasive sexing of wild and companion birds

Based primarily on phenotypic traits, birds are classified as monomorphic or dimorphic. It has been estimated that approximately 60% of bird species are monomorphic, and it becomes difficult to identify the sex during early stages of life. Bird spectators, biologists, and conservationists particularly want to distinguish between the various sexes of birds when they are in their natural habitats or the wild. Still, distinguishing the sexes of monomorphic birds at a distance has proven to be challenging for even seasoned biologists and aviculturists. Exotic and domestic birds can be sexed using a variety of techniques, including non-invasive approaches like morphometric observations, voicing, and vent sexing, as well as invasive approaches like laparoscopy and moderately/minimally invasive approaches like karyotyping and DNA-based procedures. It becomes evident that non-invasive techniques for determining a bird's sex cause less stress for the birds.