Pest control: Attract owls to the farm


By Digital team | 13 September 2018
owls
Photo: Johan Norval

Creating a safe habitat for owls on your farm is one of the easiest, most economical and environmentally friendly ways to eliminate rodents.

Grain producers and farmers who store large quantities of animal feed will tell you that they experience problems with pests such as rodents on their farms at certain times.

Farmers use various pest-control measures, but encouraging owls to a farm is one of the best ways to keep rodent infestations under control.

THE BENEFITS OF OWLS

According to BirdLife South Africa, wheat farmers in the Overberg area of the Western Cape have managed to reduce rodent infestations in their wheat fields by erecting owl perches and owl boxes.
Even timber companies that suffer damage to their trees by vlei rats use owl perches to lure owls into timber plantations. This has resulted in the complete elimination of the use of rodenticide (pest control for rodents) in timber plantations.

The presence of owls also means that farmers will tend to have no need for pesticides, which will result in financial savings. Eradicating pests from farms also reduces health risks to people and domestic animals.

According to the Endangered Wildlife Trust’s Birds of Prey Working Group, barn owls and spotted eagle owls in particular tend to live in close proximity to humans. Therefore these birds will often accept artificial nest boxes fixed to the walls of outbuildings (away from human disturbance and potential predators) and to trees.

BirdLife South Africa maintains that South Africa’s spotted eagle owl is an excellent rat catcher. The barn owl is more inclined to feed on mice such as the invasive house mouse, gerbils, field mice and striped mice. Whereas a spotted eagle owl can take as many as four rats per night, a pair of barn owls at work can kill more than 50 mice in one night, just because there is an oversupply of small rodents available.

Farmers should be cautious about the type of poisons they use on their farms, because owls are highly susceptible to secondary poisoning. Fortunately more people are becoming aware of owl conservation, but there is still more work to be done to help farmers and farm workers understand the value of owls. Such education is also helping to counter myths and superstitions surrounding these birds.

SETTING UP OWL BOXES

If the conditions are right and the owls decide to breed on a farm, you are more likely to have a larger concentration of owls.

“The amazing thing about barn owls is that they are self-regulating. They will breed to the level of the food source available – if there is enough food, they can raise up to 8 chicks at a time.”

  • To get the maximum benefit from an owl box, farmers should take great care when positioning it.
  • Owls can’t be attracted to a farm as easily as ordinary garden birds are lured to a garden, for example.
  • The owls themselves will decide whether the conditions are suitable.
  • Farmers should position owl boxes where they aren’t exposed to direct sunlight, ideally in a south-west direction, because owls aren’t fond of heat.
  • The box should be no less than 6 metres above the ground.
  • It’s also important to pick a spot away from people and animals – owls are shy, so don’t install the box near a farmhouse or in a high-traffic area on the farm.
  • Many farmers set up owl boxes near silos or close to the farm perimeter.

DIY ADVICE

Handy tips from the Endangered Wildlife Trust’s Birds of Prey Working Group: 

  • Owl boxes must be waterproof.
  • When constructing a nest box, attach a piece of wood below the entrance to the box that can act as a perch for the owl when it arrives at the nest.
  • Watch out for bees, which could invade the nest boxes of barn owls, causing the birds to abandon their eggs or chicks. If possible, deter bees by burning mosquito coils at the entrance to the box. Don’t use poison that could harm the owls and chicks.
  • If it’s difficult to access the box regularly, apply 3 layers of boiled linseed oil, which is made from the seeds of the flax plant. Once it’s dry, spray the box with Baythroid (cyfluthrin). This protects against crawling insects.

Also read: Poultry production: Rodents and your chicken houses

  • This article was written by Wilma den Hartigh and first appeared in Farming SA.