Tanzania. No evidence of natural occurrence in Kenya, although ecological barrier unclear and feral populations exist in Mombasa (now apparently hybridizing with Fischer's Lovebird (Agapornis fischeri)), as well as in Tanga and Dar es Salaam. Overlaps with Fischer's Lovebird (Agapornis fischeri) from south of Lake Manyara to Babati.
Population
Estimated population is unknown (2010).
Yellow-collared Lovebird (Agapornis personatus) [XC521389]
by GABRIEL LEITE from Cape Saint Francis Resort area, Western District, Eastern Cape, South Africa (call)
Yellow-collared Lovebird (Agapornis personatus) [XC93582]
by Martin St-Michel from Ruaha National Park, Iringa, Tanzania (flight call)
Eggs (Guide)
Clutch Size: 4 - 5
Dimensions: 23 x 17 mm (rounded)
Subspecies
Sometimes regarded as conspecific with Fischer's Lovebird (Agapornis fischeri), with which it does not, however, interbreed where naturally sympatric, although where introduced at L Naivasha and a few other highland sites in Kenya these two taxa have formed stable hybrids. Also on occasion lumped with Lilian's Lovebird (Agapornis lilianae) and Black-cheeked Lovebird (Agapornis nigrigenis). Perhaps best considered to form superspecies with all three.
BirdLife International Species Factsheet