Generally lovebirds are sexually monomorphic, it means that the male and the female of the species look alike.
But to be specific, the sexing of lovebirds falls into three categories:
1. The first group are different in their outward appearance and can be classified as dimorphic. This first group consists of the Abyssinian Lovebird (Agapornis toranta), the Madagascar Lovebird (Agapornis cana), and the Red-faced Lovebird (Agapornis pullaria).
2. The second or intermediate group are harder to differentiate by appearance. This second group consists of the Peach-faced Lovebird (Agapornis reseicollis) and the Black-collared Lovebird (Agapornis swinderniana).
3. In the third group, the white eye-ring group, there are no definite differences that can be seen. In the white eye-ring group are the Nyasa Lovebird (Agapornis personata lilianae), the Black-cheeked Lovebird (Agapornis personata nigrigenis), the Fischer’s Lovebird (Agapornis personata fisheri), and the Masked Lovebird (Agapornis personata personata). The sexing of the white eye-ring group must be determined by either a surgical probe, endoscopy, which can be done by many veterinarians or by a DNA testing, usually a blood sample or a few plucked feathers sent to be diagnosed in a lab.
General rules for determining the sex of a lovebird( not as absolutes) :
* Hens tend to be sturdier and heavier in build.
* Males often have more intense coloring.
* The female will sit on a perch with her legs spread
further apart than the male.
* Females bite harder.
* Nest building activity is stronger in the female.
* Males feed the female.
* Males sit outside nest box during the day
* Females sit inside nest box during the day.
* Females more aggressive protecting their territory.
* Females are usually dominate.
* Males sometimes abuse chicks.
The most reliable way is: females lay eggs.
An anal inspection can be done but takes experience in sexing these birds to make a fair determination. Basically there are two bones called the ossa pubes on the ventral side of the pelvis and the female will be spread wider apart than the male.
If you cannot tell for sure which lovebird is male or female,
a veterinarian can order a DNA or lab test.