Abstract

Communal roosting behaviour of Common Indian Myna Acridotheres tristis (Linnaeus) was studied from 1984 to 1990 at Trichur, Kerala. The observations were made during the roosting and departure times. Highest population of Common Indian Myna was found in the roost during June, July, August and September. Eventhough no significant difference was found in the Total Roosting Population (TRP) during different months, a significant difference in TRP was obtained between breeding and non-breeding seasons. During breeding and pre-breeding periods most of them arrived in pairs, but during post-breeding period in flocks. Time of arrival showed a significant positive correlation between median roosting time and time of sunset. Protection from predation and increased feeding efficiency due to the proximity of roost to the food sources may be the two attributes, which controlled the roosting behaviour of Common Indian Myna at this site