How Much Acreage of Grain is Needed to Feed a Barn Owl?

Barn owl:  2 kg
Barn owls eat roughly 2/3rd their body weight
2 kg barn owl eats 4/3 kg
barn owl eats 1.333 kg/day
barn owl eats 1333 grams/day
barn owl eats 1333 x 365: equivalent of 486,545 grams/year
486,545 grams per year/32 gram vole: 15,205 voles/year
vole weighs 14-50 grams
average vole weight: 32 grams
vole eats its body weight daily
over one year 1 vole eats 32 x 365 grams: 11,680 grams per year
15,205 voles/year x 11,680 grams per vole: 176,500,000 grams per barn owl per year
176,500 kg per vole per barn owl per year/3000 kg per acre: 58.833 acres of wheat
It takes 58.833 acres of wheat to sustain a 2kg barn owl for one year according to these calculations