LENSINK R (2017) Patterns in feeding and roosting of Great White Egret Ardea alba in the region Land van Maas en Waal, the Netherlands. LIMOSA 90 (4): 155-166.

In the riverine area in de centre of the Netherlands, a four year study about the roosting and feeding behaviour of Great White Egrets was conducted from July 2013 until April 2017. Weekly counts at three roosts revealed that the roost in de flood plains along the Waal (Afferdensche & Deestsche Waarden) showed a clear double peak of bird numbers in late summer and early autumn, whereas the two inland roosts (Batenburg, Ulandsestraat) had only a single peak in winter. These differences were linked to a shift in feeding habitat at the end of autumn, from aquatic feeding at the food plains to terrestrial feeding on grassland. In winter, the great majority of Great White Egrets is foraging on grassland, where voles seem to form their main prey. Arrival at the night roost shifted in the course of autumn in relation to sunset, with birds arriving later in winter. On cloudy days birds arrived earlier compared to clear days. In early autumn juveniles (with no wing moult) could be distinguished easily from adults (with wing moult). Most birds arrived solitary to the night roost. Arrival in flocks was rare, and sometimes linked to gatherings of feeding birds nearby of the night roost. However, these pre-roosting gatherings could not be considered pre-roosts as the birds would use them individually

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