Stag beetles are increasingly under pressure from intensive agriculture and commercial housing developments, meaning that private gardens are becoming even more important as safe havens. Although still familiar in the south of Suffolk the stag beetle is now a priority Biodiversity Action Plan species and it’s feared the beetle may soon become extinct at the edge of its range, such as in the West Midlands and the West Country.
By targeting the stag beetle as an important inhabitant or visitor to your garden you can help halt its decline while attracting other insects and wildlife into your outside space.
Sightings and life cycle
The male stag beetle, which can be up to 70mm long, is easily identified by his huge jaws that resemble the antlers that give his name. The females are smaller and do not have the ‘antler-like’ mandibles. Both sexes have a shiny black head and thorax, while wing cases are a chestnut brown.
You are most likely to see a male in flight on warm summer evenings between May and August, while it is searching for a mate. The female lays her eggs in decaying wood and the larvae that develop are large white grubs with orange heads that can be found in rotting wood at, or below, ground level.
It can take up to five years for the stag beetle's larvae to develop into adults. They live as adults for only a few months in the summer in order to mate.
There are two main requirements for stag beetles, dead wood and minimal disturbance. Creating a woodpile can help attract a wide range of wildlife into your garden and is possible in most outside spaces, no matter what size.
A log pile for stag beetles, while also providing shelter for invertebrates, often features wood that is partially buried to retain moisture and aid decomposition of the timber.
Here is a simple guide to creating a stag beetle-friendly log pile in your garden:
• Wood from broadleaved trees, especially oak and beech will support the richest communities of invertebrates
• Place logs in partial shade to prevent them drying out
• Fresh logs with bark attached generally provide habitats for the longest period of time and so create a wider range of habitats
• The larger the diameter of the logs the better – they should at least be the thickness of an adult’s arm
• Place logs on, or partly buried in soil. This means they will retain more moisture and makes them more valuable to the stag beetle
• Place the logs vertically in the soil as this will further increase the number of visiting insects
• Don’t pile logs too high as the timber on the top will dry out. Keep them in a moist but warm place and allow plants to grow over them to create shade and humidity