Space use and habitat selection of house crows in a tropical urban environment: A Radio-tracking study

Abstract

The house crow (Corvus splendens) is an invasive bird in many parts of Asia. A radio-tracking study was conducted on 13 randomly selected birds caught throughout the port city of Singapore. We found that house crows returned faithfully to specific daytime areas and roost sites. Home range (95% fixed kernel utilization distribution [UD1) size ranged from 1.3 to 158.1 ha while core area (50% UD) size ranged from 0.2 to 22.3 ha. Crows that have formed pair bonds remained in their core areas for longer each day, and possessed smaller home ranges and core areas compared to other birds. In the middle part of the day, house crows remained in their core areas where the bulk of feeding occurred. In addition, they used supplementary feeding sites, which coincided with afternoon gathering points. House crows in Singapore travelled only short distances (maximum = 3.5 km) to their roost sites, unlike house crows studied elsewhere. Habitat selection analyses carried out at two spatial scales showed that house crows preferred commercial and public housing land uses, corroborating results from a count-based study. This was probably due to the higher amount of anthropogenic food found in these places. By understanding the crows' movement patterns and habitat preferences, management practices can be more focused and successful. © National University of Singapore.