Broedgevallen van Bruine Kiekendief Circus aeruginosus en Grauwe Kiekendief C. pygargus in westelijk Noord-Brabant in 1994 en 1995

Creeks and marshes in the western part of the province of Noord-Brabant (c. 155 ha) were surveyed in 1994 and 1995. In 1994, 7 nests of Marsh Harriers were visited frequently; 35 eggs resulted in 21 hatchlings and 20 fledglings. From a clutch of 8 eggs 5 young fledged. Details of 14 nests in 1995 are given in Table 1, with suspected bigamy in pairs 4 and 5 and confirmed bigamy in pairs 11 and 14. Sex ratio among large nestlings was 27 males and 15 females. Prey items found on the nests are given in Table 2. In the same area, a possible breeding attempt of Montagu’s Harrier was recorded in 1994. A successful breeding attempt occurred in 1995, a single egg (probably having been part of a larger clutch) hatched on c. 1 July.