Breeding A blue Fischer with a peach faced lovebird

[Monica]

different species that belong to the same genus may be fertile but their is a 50% chance of that.

From what I've seen, there are more FERTILE parrot hybrids than there are STERILE parrot hybrids. Peachface lovebird hybrids being one of the few exceptions of being sterile.

If birds belong to the same genus, there's a much HIGHER chance of FERTILE offspring than not. Even some hybrids between different genera are FERTILE!