Holey habitat
24.1 December 2020
“Rarely a week goes by without more news of the large-scale decline of insects. The threats of habitat loss, climate change and intensive agriculture have led to nearly 10% of wild bee species in Europe facing extinction.”
“We must…help reverse this potentially devastating situation.”
“One of the simplest, and fastest ways you can help is by providing insects with a safe, purpose-built home…otherwise known as an “insect hotel.”2
“No wildlife garden is complete without an insect hotel.”2
Build an insect hotel
24.2 December 2020
Insects are by far the most numerous and diverse animals in your garden1 – typically it could contain up to 2000 species.2 But across the UK insect populations are falling dramatically due to loss of habitat and the widespread use of insecticides.2 You can help insects such as ladybirds, lacewings and solitary bees by building an insect hotel3 and provide an important place for them to nest over the summer and hibernate over the winter?2
“[Insect] hotels are easy to make and can be assembled from all manner of found, recycled or up-cycled materials.”4
Many commercial insect hotels are now available, however, with a little effort and imagination you could build your own. There’s no limit to what can be constructed using materials you may find in your shed and garden. To start with you will need a frame to contain your collected pieces of wood and bamboo. This can be made from almost anything – like an old drawer or wine box.2 Or alternatively with a few simple tools and salvaged materials you can build your own.2 There are no hard and fast rules on shape or size4– so be creative.5
We used old terracing planks and screwed them together. It’s important not to use glue as this may be poisonous to insects. The completed frame was finished with a water-based preservative. To stop the materials falling out fix either a board or a fine wire mesh to the back.3
To protect your insect hotel from heavy rain, form a pitched roof with good overhangs1 and finish it with a waterproof material – such as salvaged slates.
“An [insect] hotel is great fun to make and can provide a variety of homes…for insects of all shapes and sizes.”4
Next, fill your frame with a range of different materials. Variety is important as different species prefer different materials and hole diameters.2 Typically you can use things such as drilled timber, bamboo, and hollow plant stems4 – anything that might provide insects with a suitable nest site.
Pieces of untreated log can be used to fill your frame.6 We used a selection of off-cuts from our garden including apple, plum and oak. These should be a range of diameters and all cut to 150mm lengths.3 Many insects, such as solitary bees and serval species of wasps,6 lay their eggs in tiny holes. These can be simulated by drilling holes of 2-10 mm diameter into the ends of the logs.3 These should be as deep as possible and slope slightly upwards to prevent them from filling with rainwater. Also try to keep entrances smooth as jagged edges can damage insect wings. Leave the bark on your logs as this will provide habitat for beetles, centipedes and spiders.2
The hollow stems of bamboo cane also provide excellent nesting sites.3 These should be 5-10mm in diameter and cut into 150mm lengths avoiding knots at the ends. Similarly, old, dry and hollow plant stems can also be easily collected from hedgerows.3 Dried straw or grasses are also useful to may invertebrates who may use it for hibernation through the winter months6 and acting as filler between the other materials.
“[Insect hotels] provide a welcome home for all sorts of insects.”7
The aim is not to target any one species but rather to provide a variety of “bedrooms” for a diverse range of “guests.” 2 We also used old pinecones, thistle heads and old clay flowerpots to provide a diversity of nesting sites in our insect hotel. All the collected pieces should be pushed into the frame mixing up size and types of material.
Use a mallet to lightly tap the last few pieces into place as all need to be fitted tightly to prevent them falling out in high winds.3
“The best site is somewhere sheltered and warm.”2
The complete insect hotel should then to be installed in your garden. It should be located in a sheltered sunny position and near dense vegetation to provide shelter and feeding opportunities for the new residents.3
Places where insects can nest and hibernate are increasingly being lost as human activity spreads across the landscape.7 The small act of installing an insect hotel is a positive wildlife conservation action that will encourage many more insect species to live and breed in your garden.6
“Build [an insect] hotel – [and] help insects species thrive in your garden.”7