Action: Increase crop diversity to benefit birds
A before-and-after study in the UK found that more barnacle geese Branta leucopsis used a site after the amount of land used to grow cereals was reduced and other interventions were used.
Farmland heterogeneity is thought to be key in determining on-farm biodiversity (Benton et al. 2003). Therefore, increasing the range of different crops grown in a given year may increase the biological value of a farm.
Benton, T.G., Vickery, J.A. & Wilson, J.D., 2003. Farmland biodiversity: is habitat heterogeneity the key? Trends in Ecology & Evolution, 18, 182–188.
Supporting evidence from individual studies
A before-and-after study in Dumfries, southern Scotland (Owens 1977), found that the number of barnacle geese Branta leucopsis on a mixed agricultural site and nature reserve increased from 3,200 in 1970 to 6,000 in 1975 following a reduction in the amount of cereals grown on arable land. From 1970 onwards, only 16.7% of the 50 ha of arable land was used for cereals. In addition, all cereals were undersown (see ‘Undersow spring cereals’) and no stock were allowed to graze on the arable land after November (see ‘Reduce grazing intensity on permanent grassland’).