Resultaten van slaapplaatstellingen van blauwe kiekendieven Circus cyaneus in de kustpolders en het krekengebied van NO-Vlaanderen in de winters 1990-1991 en 1991-1992

J Seys

Research output: Contribution to journalA3: Article in a journal without peer review

240 Downloads (Pure)

Abstract

In January 1989 and 1990 simultaneous Hen Harrier Circus cyaneus roost counts were carried out in the Flemish coastal polders. In the following winters (1990-'91 and 1991-'92), similar counts were organized on five different dates as part of the "Hen Harrier winter Roost Survey" of the BTO IR. Clarke). The polder area of N.E.-Flanders was counted too. This paper provides a brief outline of these censuses. 16 roosts were visited in 1990-'91 and 12 ones in 1991-'92. Among them 10 and 7 ones were at least once occupied. The most important roost is and remains the Blankaart in Woumen. The next important ones are the Zwin in Knokke and the Oostpolder-kreek in Sint-Jan-in-Eremo. The numbers of the Hiddle Coast are traditionally low: only a few scattered specimen staying over in the Rattevalle or the Kleine Keignaert. The total numbers of January 1991 were 53-57. In January 199233-38 specimen were counted. In comparison to the fairly high numbers of the previous winter, 1991-'92 has low ones. The size of wintering Hen Harriers in het Flemish coastal polders can be estimated at 35-100 specimen. To this, one must add the 5-10 ones in the marshland of N.E.-Flanders. These relative high numbers in comparison to results of neighbouring countries, stress the great importance of our polders for Hen Harrier. Further investigation is necessary in order to find a solution for unresolved questions concerning winter distribution of this species and therefore colour-marking study can play a major role.
Original languageDutch
JournalMergus
Volume6
Pages (from-to)229-241
Number of pages13
Publication statusPublished - 1992

Cite this