Nesting characteristics and breeding success of Rose-ringed Parakeet Psittacula krameri in urban and natural areas

抄録

The present study was conducted to identify the effect of urban and natural areas on nesting and breeding success of Rose-ringed Parakeet. Nests of Rose-ringed Parakeet were monitored using a combination of camera surveillance and direct observations along transect lines. Cavity availability and use was compared between natural and urban areas. A total of 171 cavities were located, of which 106 contained active nests. The number of available cavities and the proportion occupied were both higher in natural areas than in urban areas. A uniform/cosine model estimated that mean nest density was greater (P<0.05) in natural areas (136 nests/km²) than in urban areas (130 nests/km²). The preferred trees used for nesting were Banyan Ficus benghalensis (22.8%) followed by Chinaberry Tree Melia azedarach (20.4%), Paper Mulberry Broussonetia papyrifera (14.6%), Chir Pine Pinus roxburghii (14.6%), Southern Blue Gum Eucalyptus globulus (11%), Mango Mangifera indica (9.3%), and White Mulberry Morus alba (12%). The greatest number (P<0.05) of successful breeding cavities was recorded in the middle of trees (42.5%) at heights of 6.1–9 m (72.6%) above ground. Mean cavity depths were significantly greater (P<0.05) in urban areas (9.95±0.5 cm) than in natural areas (8.71±2.1 cm), while mean entrance diameter was 6.19±1.9 cm in natural areas and 5.65±0.2 cm in urban areas. Clutches of five eggs were the most common. Hatchling and fledgling successes were higher in natural areas than urban areas, with egg survival probability (70.0%) and nestling survival probability (94.0%) higher in natural areas than in urban areas (37% and 60%) respectively. It is concluded that the breeding success of Rose-ringed Parakeet varies between urban and natural areas.