Abstract
The Red-brewed Amazon does not readily breed in captivity, and to date few breeders can report breeding success. However, Laro Parque Fundaci6n (LPF) has developed some techniques that seem to result in a siqnitcant number of successful breeding attempts, and we are continuing our experiments to re Che our breeding techniques with this highly endangered species.
At LPF the species was trst kept in the conventional manner in isolated single pairs. However, because over the years no breeding occurred, some new procedures were introduced. Initially we tried a method where a group of six pairs were placed together in a group aviary, 15 meters long, 4 m wide and 3.5 @ m high (for those of you not familiar with the length of a meter, it is a bit over 3 feet). Small separation cages (at least 6 cages) were attached to the group aviary, with the top mesh of each separation cage being at the same height as the top mesh of the group aviary. Each separation cage was approximately 1.5 m long, 1 m wide, and 1 m high, containing perches, an opening allowing access to the group aviary, and having a nest-box at the far end. The opening into the group aviary could be closed with a mesh partition.
As a result of living in this rock situation, several pairs came into breeding condition. Each pair established itself in a separation cage and laid eggs in the nest-box. The eggs were removed for artitcal incubation and the chicks hand-reared. The rrst year ten young were produced. No changes were made in the setup, but breeding success in the subsequent year was only Die young. In the following three years !with nothing changed -- no breeding occurred. In 2001 the group was shifted into another large aviary. In that year there was only one clutch of two eggs, which were artitcially incubated and the two young hand-raised.
In 2002, again the species did not breed. Thus we decided at the end of 2002 to separate the entire group, and all other pairs in the collection, and maintain the birds individually for a period of approximately three months, without contact with their conspeciccs. Each bird was maintained in a cage suspended 1.25 m off the ground and measuring 3 m x 1.5 m x 1.5 m high. The twenty two reproductively mature Red-brewed Amazons were distributed in suspended aviaries throughout the entire breeding center.
Following about 3 months of isolation from each other, the birds were brought together at the end of February 2003 into three different groups. Six pairs were placed into a Dght measuring 20 m x 12 m x 3.5 m high. Three pairs were placed in a second Dght 10 m x 10 m x 4 m high. As controls, two pairs were each placed into individual suspended cages 5 m x 1.5 m x 1.5 m high. The individuals in the suspended cages kept themselves apart and did not produce eggs. But four pairs laid eggs in the six-pair Dght and two pairs laid eggs in the three-pair Dght. Again the eggs were taken for artitcial incubation and hand-rearing, and altogether ten young birds resulted. However, we noted that there was also a large number of....