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Acta Ornithologica
|
1998
|
tom 33
|
nr 3-4
143-148
A method estimating the spring density of Grey Partridge using male call counts was tested. Vocal activity was found to be relatively constant between mid March and mid April. In this period, the average number of males heard at randomly- selected points in an area was strongly correlated with Partridge population density. Counts of calling males may be used to determine the spring density of Partridges: indiv./km² = 3.38x¹‧¹¹ or pairs/km² = 1.45.x¹‧¹⁶, where x = mean number of males heard at selected points. The number of randomly-selected single listening points (between 1 point per km² and 1 point per 10 km²) should be chosen in accordance with the size of the area and the aim of determining the density.
The aim of this paper is to review our knowledge about two important small game species living in agricultural landscapes - the brown hare and grey partridge, i.e. about changes in their hunting bag, reasons for their population decline and conservation methods. In the 1960s and 1970s, the hunting bag of hares typically varied from 400 to nearly 700 thousand individuals, and the bag of partridges fluctuated widely from 10 to almost 750 thousand individuals. Unfortunately, a considerable decrease in the numbers and hunting bag of small game species took place in the recent decades, especially in the 1990s. In the year 2010, only about 17 thousand hares and 3 thousand partridges were shot in Poland. The decline in partridge numbers in the 1990s was connected mainly with the deterioration of reproduction success, including both brood production rate and chick survival rate. In the case of hares, the decrease of young production and adult survival rate were found in the last decades. Increased abundance of some predator species, particularly red foxes, and negative changes in farmland habitat were mentioned as the main reasons for the negative trends in small game numbers. Therefore, predator removal and habitat management should be primarily applied as the main methods of small game conservation. Moreover, it is often argued that in the case of both hares and partridges, conservation by wise use of their populations by hunters may be taken into account.
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