Encourage pest-eating birds, toads, bats and wasps by giving each what it needs: nest boxes for insect-eating birds, a shaded damp shelter and a shallow pond for toads and frogs, a roost for bats and tolerance of small parasitic wasps. None of them is reliable alone, and each has a cost, since birds also eat seed and fruit, and bats must never be handled with bare hands because of rabies.
Predator encouragement is the provision of habitat for animals that eat crop pests.
Birds
The carrier recommends nest boxes for bluebirds, wrens and swallows, which eat insects. Match the hole size and the box height to the species you want, and mount boxes where predators (cats, snakes, raccoons) cannot easily reach. Perches, a water dish and some brush or hedge give cover.
Costs: seed-eating birds raid seedbeds and ripe fruit. Net the crops that matter, using taut netting that cannot trap birds (Physical Controls). Birds of prey and owls that take rodents need perches and nest sites; the carrier says barn owls eat large numbers of rodents but gives a figure (“1,000+ per year”) with no source, so treat it as a rough indication.
Toads And Frogs
Toads eat slugs, cutworm moths, beetles and many other insects at night. Provide:
- A shaded, damp refuge in the beds: an overturned clay pot with an entrance chipped in the rim, or a flat stone propped up.
- A shallow pond or water dish; amphibians breed in water.
- Cover of mulch and low plants. Do not use slug pellets, salt or any poison where toads live.
The carrier states that “a single toad eats 100+ insects nightly”. No source is given, so this is not a number to plan from.
Bats
Bats eat large numbers of night-flying insects, including moths whose caterpillars damage crops. Provide a bat house on a south- or east-facing wall or pole, high above the ground, away from predators and artificial lights. Bats may ignore a new house for a season or more.
Bats can carry rabies
Never handle a bat with bare hands, and never touch a bat found on the ground, in a house or acting strangely. A bite or scratch, or any contact you are unsure about, calls for immediate washing with soap and water for several minutes and urgent medical advice; rabies is almost always fatal once symptoms start (Disease Awareness, Wound Management). Keep children away from bat houses and from fallen bats. Toads secrete a skin toxin that irritates mouth and eyes and can poison dogs that mouth them, so wash hands after handling.
Wasps
Parasitic wasps are tiny, do not sting people, and lay eggs in caterpillars and aphids. They are encouraged by small flowers (alyssum, dill, parsley in bloom) (Beneficial Insect Attractors). Larger paper wasps and yellowjackets also take caterpillars but sting. Tolerate nests away from doors, paths and harvest areas; remove those within a few metres of where people work.
Method
- Choose one or two species to attract, not all at once.
- Build and place the habitat before the season the pest arrives.
- Remove what harms them: poisons, cats at nest boxes, mowing in the nesting season.
- Log the results. Count pests on beds with and without the habitat for a few seasons.
- Protect crops that birds will raid.
Common Mistakes
- Boxes without predator guards. They become feeding stations for cats.
- Placing a bat house in shade or on a low post. Bats will not use it.
- Treating the number of insects eaten as certain. The figures are rough.
- Trying to attract everything. The hedge that shelters toads also shelters slugs.
What’s Next
- Learn next: Chicken Tractors for Pest Reduction — managed livestock
- Combine with: Predator Protection — protecting your own animals from predators