Nest van Bruine Kiekendief Circus aeruginosus telt 10 eieren

In 2005, a traditional breeding site of Eurasian Marsh Harriers in the southwestern Netherlands (near Zaamslag) was not yet occupied on 11, 16 and 23 March; a male and female were present from 31 March onward. Prey transfer was recorded on 11 April, and again on 21 April. The nest was checked on 15 May (female sitting), and contained 2 small chicks and 8 eggs. No adult birds were seen on 8 June, but during the next visit on 12 June male and female (both in adult plumage) were present. Four nestlings (2 males and 2 females, wing lengths resp. 228, 192, 262 and 258 mm, body masses resp. 532, 526, 712 and 722 g), 2 unhatched eggs and a broken egg were found on the nest. Fledgling(s) were noticed on 24 June and 9 July. More than a single female was never recorded at this nest (presumed to be the same individual), but the possibility of two females having laid in the same nest cannot be ruled out. Unfortunately, the eggs were not measured.