Colony Breeding

Usually Lineolated Parakeets raise youngsters in colony breeding without any problems, too. But for that you always should put together more than two couples, never just two (Vriend 1999).
Merely supernumerous male birds sometimes inhibit the brood events and should be removed from the aviary during the brood period (de Grahl). Also dominant couples are able to prevent the brood of other couples completely. Thus at Roeder (Buedingen) just one dominant couple breeds at colony breeding. In contrast Henig (Rottendorf) observed such dominant birds just rarely. But, for the sake of peace, they should have the chance to breed alone. Usually this is no problem with these couples.
Rosemary Low (1983) emphasises, that colony brood at Lineolated Parakeets promotes the breeding readiness of the birds. Solitary kept couples started to breed just hesitantly or even never. Another advantage of colony breeding is presented by Low: One don't have to be concerned about the gender designation of the birds. Because in an aviary with a flock of Lineolated Parakeets the couples can find themselves free and easy.
But sometimes a concrete mating of two birds is necessary, e.g. for the breed of special colours. If you all the same don't want to turn down colony breeding, Laegel (Buxtehude) recommends to let this couple breed in a box for the first time. Therefore no nesting box should be provided during the first 14 days, because that might lead to vehement arguments, if the birds don't like each other. Once they successfully reared youngsters, they usually will stay together even in a flock of birds.

Generally the combativeness of Lineolated Parakeets increases during the breeding period. Beck (Lilienthal) refers to defence of the breeding place especially against conspecifics. Particularly cocks tussle heatedly for the most attractive breeding places, emphasised by daunting and threatening postures. So it is essential (as known for all parrots, where colony breeding is possible) to have at least two times more nesting boxes than potential breeding couples in the aviary. Additionally they should be positioned in approximately they same height (Alderton 1997).
Occupied nesting boxes are defended (Nixdorf/Wolfsburg). Koch (Kuerten) in contrast speaks about a territorial defence around the nest box, which can be observed just during selection of the nesting place, but later not any more. Roeder (Büdingen) saw at one of his breeding couples, that the hen was forced to stay in the nesting box by the cock every time she tried to leave it.
Just sometimes these kind of arguments lead to serious injuries.
This is different at obviously aggressive birds, which can be found at the Lineolated Parakeets as well. Nixdorf (Wolfsburg), for instance, owns one cock, which kills his chicks 3 days after hatching and even harms the defending hen. Thereby the aggressive behaviour seems to be triggered by the begging sounds of the chicks.
Also Franz Pfeffer (Plattling) told me, that every now and then there are turbulent, aggressive birds. During breeding period this behaviour seems to be strengthened.
But those birds are rather exceptions. Otherwise Lineolated Parakeets are peaceful also during the breeding time.
At times one can read about couples, that share nesting boxes with another couple (Wagner 1998). At Laeuser (Arndt 1986) two hens shared one cock, the hens bred together in one nest box. Also Weber (1992) was able to observe similar events. It is possible, that the youngsters of a previous brood feed the chicks of the new brood, as well as completely uninvolved birds. Usually this is tolerated by the parents (Wagner 1998).