Abstract
Between September 2003 and July 2006, the reproductive biology and time budget of the Ruddy Shelduck Tadorna ferruginea was studied in the wetland complex of Oum el Bouaghi, north-east Algeria. Our results indicate a marked post-breeding dispersal of the Ruddy Shelduck to the eastern Hauts Plateaux where more than 1 000 birds (one-third of the estimated north-west African population) may gather in autumn. Dispersal is again conspicuous at the end of the wintering period when most birds leave the area to return to their breeding grounds. In 2004 and 2005, successful nesting was recorded at five sites. In both years, territoriality was exhibited from March to June and broods, ranging from nine to 14 chicks (mean = 11.1 ± 1.8, N = 16), were recorded between 21 May and 7 July. We also monitored the diurnal time budget of the Ruddy Shelduck over a two-year period. Feeding, most intense in late autumn and winter, occupied 50.6% of the daily activities with a distinct gradual seasonal decrease coinciding with the start of the breeding period. Ruddy Shelduck relied more upon surface feeding in shallow waters but displayed flexibility of feeding behaviour when water level fluctuated.