TURNHOUT C VAN & VERSTRAEL T (1999) Does the size of the beechmast crop influence the numbers of wintering seed eaters in The Netherlands?. LIMOSA 72 (4): 162-168.

The numbers of Marsh Tit Parus palustris, Great Tit P. major, Nuthatch Sitta europaea and Brambling Fringilla montifringilla counted in The Netherlands in the winters of 1980-94 were found to be related to the size of the beechmast crop in the preceding autumn, according to data from Point-Transect-Counts of wintering birds, as organised by SOVON Bird Census Work The Netherlands and Statistics Netherlands. This relation may be caused by high numbers of birds from northern breeding areas in winters when food supply is high and a lower autunm and early winter mortality when many beechnuts are present, or by factors fluctuating along with both numbers of birds and beechmast

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