Feeding Behavior in Ibisbill (Ibidorhyncha struthersii)

Abstract

Feeding behaviour of Ibisbill was studied in the Kashmir Himalayan River Sindh. Observations on the foraging behaviour were made at six selected sites. The food items consumed by the bird during the study period include aquatic invertebrates, insects, and fishes of smaller size. In a novel finding, the bird was found to feed on a vole (n=2). The main technique used for obtaining prey items was probing, however, pecking was also employed for feeding the larger prey items. A total of 820 observations revealed that the foraging accounted for about 44% of activity time budget in summer while as in winter the foraging was found to contribute to about 62%. Diurnal behavioral rhythms of foraging showed a peak during morning hours (8:00 to 10:00) in summer and in winter the peak was observed during the afternoon (12:00 to 15:00). The probing rate was higher (19.23±0.70) in winter and lower (17.39±0.67) in summer, whereas an inverse trend was observed for capture rate which was higher in summer (8.61±0.46) and lower (5.86±0.27) in winter. The Sindh river was also found to witness anthropogenic activities such as extensive mining (extraction of sand, silt and boulders) and tourism related activities, having a negative impact on the habitat of the bird. From the conservation viewpoint, these habitat impacting activities in this river shall be controlled, to ensure better feeding conditions for Ibisbill and other waterbirds.