KURSTJENS G, DIERMEN J VAN , NOORDEN B VAN & WEIDE M VAN DER (2003) The Corn Bunting Miliaria calandra: recent population trend, habitat use and perspectives related to habitat management in Dutch river forelands and arable land. LIMOSA 76 (3): 89-102.

In this paper we describe the trend in breeding numbers of Corn Buntings in The Netherlands in the period 1995-2001. The breeding distribution is now limited to chalk-rich riverine soils and loess plateaus in the hilly Southeast, mainly in the southern part of the Netherlands in the Province of Limburg. Arable land on marine clay soils in the North (Groningen) and Southwest (Flanders) was lost as breeding ground in the 1990's, in spite of large scale set-aside programs in the northern regions. We try to establish whether Corn Buntings benefited from renaturation schemes in river foreland. Here agricultural land was transformed into natural habitat, mainly by removing clay from sand and restoring old gullies. River dynamics so regain their effect (flooding, sedimentation, erosion) and areas are maintained under low density grazing. Under these conditions within a few years pioneer vegetations, natural grasslands, scrub and young forests of Salix spp. and Populus nigra arise.
      In Limburg the Corn Bunting population decreased from 65 territories in 1995 to 10 in 2001. Two small strongholds remained near the city of Maastricht, one in the Meuse valley and another on the plateau (Oud Caberg). In the remaining part of the Netherlands numbers varied between 10-20 territories, only peaking extraordinarily in 1997 when 25 territories were found in Waal forelands (the main branch of the river Rhine). We conclude that Corn Buntings only temporarily or incidentally profit from renaturation in Meuse and Rhine forelands. In Limburg (Meuse valley and plateau) the species seems to be tied to traditional breeding locations and has not yet exchanged its deteriorating agricultural plateau habitat (preferably small-scale farming with high crop diversity and predominantly cereal fields) for semi-natural grassland in river foreland. Without this habitat shift the Corn Bunting has hardly any breeding perspectives in Limburg, unless it gains profit from a conservation scheme for the Common Hamster Cricetus cricetus. This will create 500 ha at maximum of optimally managed fields scattered over 11 locations on the plateaus.
      In the forelands of the Rhine branches low-intensity farming, preferably harvesting hay in mid July, seems to contribute most to the benefit of Corn Buntings. The area under this type of management nowadays is far below what it used to be in 1960-80. Here too, the species might profit from conservation measures for a different species, the Corncrake Crex crex. Apart from this, Corn Bunting numbers in river foreland correlate with river discharge levels; flooding of foreland reduces the area of habitat that becomes available in time for settlement. Recently, winter observations have become very rare in The Netherlands, except for southern Limburg. Possible effects of winter habitat quality on the breeding stock are discussed for lack of knowledge of the specific Dutch situation. The overall decline in Dutch breeding numbers fits into the Northwest-European trend and breeding-range contraction. It is recommended to initiate a winter monitoring scheme, and to collect all spring observations in order to monitor dispersal and the likelihood of settlement in potential breeding habitat in different regions.

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