SOVON (1988) Keeping up: Grouse in 1986 and 1987. LIMOSA 61 (3): 193-194.

Black Grouse Lyrurus tetrix In 1986 SOVON the annual count of the black grouse taken from the National Institute for Nature (RIN). This study was well under the umbrella of special-Types-Praject (BSP) for braedvogels be appropriate. It will be commonplace that Grouse difficult circumstances (Vogel 35 Year: 302308.309 - 311). The malaise is not limited to Netherlands but throughout the lowlands NWEuropa in its grip. Nor is it something of the recent years. Over the past 50 years has grate lines every ten years to halve the population place. That seems kind in our region least, the inevitable doom to be heading

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