Bat Infestation in a Garden

Greater short-nosed fruit bat (via Wikimedia Commons, CC BY-SA 4.0)

A bat infestation in a garden can be a significant problem for homeowners. Bats can damage plants, fruit trees, and other garden structures, and their droppings can pose a health risk to humans and pets. In addition, bats can carry diseases such as rabies, which can be transmitted to humans and animals through bites or scratches. It’s essential to take steps to prevent or eliminate a bat infestation as soon as possible.


  • Presence of bat droppings (guano) on or around the garden, especially on surfaces under eaves, on decks, patios or near entry points.
  • Damage to plants, fruit trees, and garden structures, such as holes in leaves, flowers, and fruits or gnawing marks on wood.
  • Bats seen flying around the garden at night, particularly around dusk and dawn, when they are most active.
  • Unusual noises, such as squeaking or fluttering, coming from the garden at night.
  • An increase in the number of insects in the garden, as bats feed on insects, and their presence may attract more.
  • Bat colonies, often found in tight spaces such as attics, barns, sheds or under roofs.
  • Urine stains, oil marks or greasy smears around entry points or roosting areas.
  • Unpleasant odors coming from the roosting area.
  • Bats found inside the house or other structures on the property.
  • Bats found dead in the garden or around the property. It is important to keep in mind that not all bats are carriers of diseases, but it is always recommended to take precautions and have a professional inspect the area and handle the situation if you suspect a bat infestation in your garden.

What is a Bat

  • Small mammal with wings, that are covered in a thin layer of fur.
  • Two legs with clawed feet, that are used for grasping and clinging to surfaces.
  • Two wings with fingers (that extend from the shoulder blades) that are flexible and have a complex network of bones and muscles, allowing them to fly and maneuver with great agility.
  • Dark brown or black fur, that can be smooth or glossy depending on the species. Some species have lighter fur on their belly.
  • Pointed ears, that are usually located on the top of the head and are often visible through the fur.
  • Small, sharp teeth, that are adapted to eating insects, fruits, or nectar depending on the species.
  • A body length that ranges from 3 to 9 inches, depending on the species.
  • A body weight that ranges from 0.7 to 1.5 ounces, depending on the species.
  • A head that is relatively large and triangular in shape, with a pointed snout.
  • A pair of large, round eyes that are adapted to seeing in low light conditions.
  • Bats can be difficult to spot when they are roosting, as they tend to hide in tight spaces, such as caves, attics, and behind shutters, and only fly out at night. It’s essential to observe the behavior of bats and to take into account the time of day and location when trying to identify the bat species.

Treating a Bat Infestation

It may be necessary to use multiple methods to effectively treat a bat infestation in a garden. For example, exclusion and habitat modification can be used to prevent bats from entering the garden in the first place, while repellents and trapping can be used to encourage bats that are already present to leave. In some cases, it may also be necessary to use a combination of methods, such as exclusion and repellents, to achieve the desired result. It’s important to consider the specific circumstances of the infestation and consult with a professional to determine the best course of action.


  • Locate all potential entry points such as holes, cracks, and gaps in the walls, roof, and eaves of the building and any other structures in the garden.
  • Seal all entry points using materials such as caulk, steel wool, expandable foam, or hardware cloth.
  • Use exclusion devices such as one-way funnels or cones to allow bats to exit the roost but not re-enter.
  • Be sure to check for and seal any new entry points that bats may find.
  • It is important to check for bats inside the roost before sealing the entry points, to avoid sealing bats inside.

Habitat modification

  • Remove or trim trees and shrubs that may be providing roosting or foraging sites for bats.
  • Install bat houses or other roosting structures in the garden to provide alternate roosting sites for bats.
  • Keep the garden clean and tidy, removing piles of leaves, wood, or other debris that may attract bats.
  • Keep the grass short and trim the hedges to reduce cover for bats.


  • Use ultrasonic devices, strobe lights, or other types of repellents to discourage bats from roosting in the garden.
  • Spray repellent sprays or granules containing predator urine or other scent-based repellents around the garden.
  • Hang bat houses in the garden, as bats are territorial and may be less likely to roost in an area where other bats are already present.

Trapping and Removal

  • Use one-way exclusion devices, such as funnels or cones, to allow bats to leave the roost but not re-enter.
  • Use humane live traps to capture bats and release them in a safe location, far away from the garden.
  • Hire a professional to safely remove bats from the garden, as they may carry diseases, and it’s important to handle them carefully to avoid injury.
  • It’s important to note that trapping and removal should be done as a last resort, after all other methods have been exhausted.