大象传媒

Barn owls are under threat in the UK as they're not producing enough young to keep the species going. This clip looks at the food chain of owls - grass/ voles/ owls. The number of small mammals directly controls the number of owls that can live in a small area. Habitat is key - voles need long grass to hide and nest in. Short, well grazed grass is no good for voles, so owls won't catch enough small mammals to raise their young unless they find suitable grassland.