Factors affecting the level of damage by wild boar in farmland in north-eastern Poland.
BACKGROUND
There was an unchecked increase in wild boar population and in the damaged crops in Poland in 2010, and the amount of compensation reached €12.4 million. The objective of the present study was to establish the factors affecting boar-related damage and to verify the effectiveness of protective strips used again wild boar pressure upon fields.


RESULTS
Damage was positively correlated with the wild boar population density, the farmland-forest ecotone index, the proportion of deciduous stands, the Simpson index for dominant tree species and the age class of forest stands. The relationship between level of damage and feeding strips was not significant. Stepwise regression explains 55.6% of the variability of a given feature affected by the wild boar density, the forest-field ecotone index and the Simpson index for the age structure of the forest. During 5 years, the compensation for damage caused by boar amounted to €34.2 million, whereas the revenue from carcasses sold amounted to €9.5 million.


CONCLUSIONS
Protective strips do not reduce the damage to crops, and so the offer of high-protein food on these strips, which increases reproduction rates among wild boar, should be discontinued. Reduction in the level of damage can only be achieved by a radical reduction in numbers of wild boar.
Department of Ecology, Wildlife Research and Ecotourism, Institute of Biology, Pedagogical University of Krakow, Krakow, Poland. fracko@poczta.fm
Witold
W
Frackowiak
Stanislaw
S
Gorczyca
Dorota
D
Merta
Marta
M
Wojciuch-Ploskonka
D000818:Animals; D016468:Forestry / Q000191:economics; D008460:Meat / Q000191:economics; D010571:Pest Control / Q000191:economics / Q000379:methods*; D011044:Poland; D011156:Population Density; D034421:Sus scrofa / Q000254:growth & development / Q000502:physiology*; D014197:Trees / Q000254:growth & development / Q000469:parasitology*