THE LIFE CYCLE OF A STAG BEETLE

TAKES AT LEAST 3 YEARS IN THE UK

Adult stag beetles (Lucanus cervus L.) live out in the open for a few weeks but prior to that they lead a mysterious long life underground.
Below is a diagram attempting to illustrate a minimum life cycle duration of 3 years * compressed in a circle, starting at the top and going clockwise; the years are notched. If one imagines that the circle is a clock-face of one hour, then the flying season would last about 5 minutes.

To view this diagram just move the mouse pointer over the numbers. This way you can see the corresponding text appear in the box on the right hand-side of the life cycle.

Stag beetles - All they need is love and wood

This life cycle was designed by Maria Fremlin, based on her research*, and illustrated by Carim Nahaboo.
Higher resolution digital files are available on request, but they incur a charge. Also, a limited edition of A3 prints is on sale. If interested, please, contact Carim Nahaboo.

* The current life cycle duration of “at least 3 years” is based on Maria Fremlin's research carried out in Colchester, North-east Essex, UK, listed below; but it could be one year longer longer if, for instance, there has been a colder winter/spring, which will delay the larval development. However, in the Continent, the minimum life cycle duration is 4 years, this probably because the beetles are bigger than the ones in the UK, thus take longer to develop, and/or other climatic factors.
1. Rearing trial in a terrarium in a well ventilated garage; eggs laid in July-August 2009, teneral imagos in September 2011 (unpublished).
2. Stump cut in early 2009, female stag bbetle observed going into a crack in late June 2009 [PDF]; followed by the emergence of two males in 21 May 2012 [PDF].
3. Pile of freshly cut wood chips made in 28 June 2010, teneral imagos in October 2012 [PDF].
4. Apple stump buried with lots of wood chips next to an existing nest, in March 2010; emergence holes June 2013 [PDF].
5. Large horse chestnut tree felled on October 2011, a couple of emergence holes in early June 2014. This stump soon developed fruiting bodies of turkey tail Trametes versicolor, which is strongly associated with the presence of stag beetles; for more see Model stag beetle nest.

Last modified: Jan 31 2023