BREEDING SEASON AND PRODUCTIVITY OF MONK PARAKEETS IN CORDOBA, ARGENTINA

NAVARRO, J.L:; MARTELLA, M.B.; BUCHER, E.H.

WILSON BULLETIN

Springer

Año: 1992 p. 413 - 424

0043-5643

We studied the breeding productivity of populations of the Monk Parakeet (Myiopsitta monachus), at Arroyito and Jesus Maria, Cordoba province, Argentina. In Arroyito, nests were in introduced eucalyptus trees, whereas in Jesus Maria nesting wasentirely in native tree species. Egg laying started on around 1 November, although onset of breeding varied significantly among years within a three-week period. Start of egg laying within the populations was extended for nine weeks on average. The percentage of occupied nest chambers found with eggs was significantly higher at Arroyito (9 1%) than at J. Maria (overall mean 53%). At Arroyito, mean first clutch size was significantly higher (6 eggs) thanat J. Maria (5.4 eggs). Replacement and second clutches were significantly smaller than the first clutchesi n both areas. Hatching successd id not differ between areas (58%, both combined)but differed significantly among years at J. Maria. A higher percentage of nestlings reached fledging age at Arroyito (53%) than at J. Maria (42%). Mean number of young fledged per breeding pair was 2.2 at Arroyito and 1.4 (overall) at J. Maria (range: 0.5-2.3).The apparent preference exhibited by Monk Parakeets for nesting in eucalyptus trees againstlow native vegetation could be a result of the higher productivity of breeding pairs in the former habitat. The Monk Parakeet has a lower fledging and breeding success than otherparrots. Due to its large clutch size, however, it has one of the largest productivities amongpsittacids. Received I Aug. 1991, accepted 1 Feb. 1992.