BEKHUIS J, BINSBERGEN F VAN & BIEWOLD F (1992) Keeping up: Does aid for the Grouse on time. LIMOSA 65 (2): 75-76.

Black Grouse Lyrurus tetrix In Limosa 6I: 193-194 published an overview in which The spread of black grouse in 1986 and 1987 are discussed. Unfortunately, we found that the position has since been further reduced. In the years 1988-91 are respectively 43, 29, 40 and 40 males counted (presumably some investments or escapees not included). The Dutch grouse tooth this is a temporary low. Since 1976, when the state already hard declined, the species disappeared from the provinces of Utrecht (in iaatste 1979), North Holland (1981), Limburg and Friesland (1984), Ontario (1986) and Ontario (1988). the Grouse is now confined in Ontario (five sites in 1991) and England (two sites in 199 I) (Figure I).

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