General Advice for Bat Boxes
- Tree trunk should be tall and straight at least to 4m
- Location should be very sheltered and the box must not have gaps to let in breezes
- Species not important. Typical species include: Oak, Monterey Pine, Sycamore, Elm, Chestnut, Beech, Ash
- Tree should be live (not dead). Bat boxes are for the long term and dead trees are sometimes chopped. In any case dead trees may already be used by bats
- Best to avoid trees with ivy. Even if present in small amounts, it does grow quickly and can obscure the entrance to the roost.
- Safety: Although it is unlikely that a Kent box will fall, it is probably a good idea not to place it over any well walk paths
- Natural undergrowth is better if possible, rather than gravel or paving. An area with water nearby is advantageous eg pond, swimming pool, stream
- Trunk of tree should be >40cm in diameter as it is easier to fasten boxes to a less curved base.
- There should be a clear flight line to entrance of box. This is especially important, as bats will not negotiate a convoluted path to the box through branches and leaves
- If you have the time and energy, it is best to place box on a long pole >4m. This does involve a lot more work though, and in general trees work well in Jersey
- Ideally fixings should be made with aluminium allow which can be cut through without damaging chainsaws should the tree fall and need to be cut up. Each box should have 3 flexible brackets attached to allow for the curvature of the tree, 2 at the top and 1 at the bottom. You can easily buy these brackets from B&Q or Andersons. You may need to order aluminium nails but if it is your own garden you may prefer to use metal screws.
- Best height for the box is above 3m (up to 4m is best).
- Best to place box with a southerly aspect if possible as bats like lots of heat, and they tend to use boxes in Spring and Autumn. Rarely in summer and occasionally in winter.
- A quiet undisturbed area is better. No light pollution on or anywhere near the box.
- If bats do occupy your box, they will show site fidelity unless the box deteriorates. Bats hate draughts. They will not be there all year but will return when conditions suit them. They will probably also have other roosts so will not be there every day.
