How To Tell a Male Lovebird from a Female
Lovebirds are monomorphic (the opposite of dimorphic) which means that male and female members of the species cannot easily be “sexed”, or told apart. However, there are methods – you just need to know how; but bear in mind that the only 100% certain way is to carry out a DNA test (or wait until the lovebird lays eggs, obviously!)
Observe the beak. The beak of the male is slightly longer with a longer hook. The female's beak is a little broader. The female's head and shoulders are slightly broader. Having a correctly sexed bird for comparison is preferable.
Hold the lovebird belly up in your palm. Gently pin it down with the fingers of the same hand. With your other hand, put your finger between its legs. Feel two bony points just above the tail. If the points are close together the bird is male and if they are further apart it is female. This method is not exact and requires practice and comparison with other birds.
Female lovebirds will often act unusually aggressively if they are getting ready to lay an egg. A male lovebird is usually gentle and laidback. However, each bird is different and you may have a male with a consistently aggressive nature.
Take your lovebird for a DNA test. The veterinarian will cut the bird's toenail far back enough to draw blood, which will be sent off to a laboratory for DNA testing.