Rare River Dragon in Danger

Rare River Dragon in Danger - British Dragonfly Society

Citizen science project reveals the plight of the UK’s only Clubtail Dragonfly

For the past three years, 2017-2019, British Dragonfly Society volunteers have searched over 200 miles of river bank on the hunt for the elusive Common Clubtail. The results of their work have now been analysed.

Despite the name, the Common Clubtail (scientific name: Gomphus vulgatissimus) is a rarity, only found on a handful of lowland river systems in England and Wales. Even the most avid naturalists will be lucky to see one as the Dragonfly spends most of its life in the river depths as an aquatic larva. As an adult the Common Clubtail hides in woodland chasing hunting insects through the tree tops.

The British Dragonfly Society launched the Clubtail Count project in 2017 with the aim of mapping the location of Clubtail populations in the UK. Volunteers spent sunny days from May through to July each year searching river banks for the Dragonfly’s exuvia: the shed outer skeleton left behind when a larva turns into an adult (a transformation called ‘emergence’). Between them, over the three year period, the 180+ volunteers found almost 2000 exuviae.

Findings varied greatly between river systems but overall the River Severn proved to support the most significant population with Clubtail reported all the way from Tewkesbury, north passed Shrewsbury, to where the Severn meets the Welsh border. The Clubtail was also reported to be doing well on the lower Wye around Monmouth, the Lower Teme downstream of Tenbury Wells and on the River Dee between Wrexham and Chester.

Unfortunately, the report was not all good news; despite once being widely distributed on the lower reaches of the River Avon, the river system only produced one Clubtail sighting during the three years of the project. Common Clubtail could also not be found within its historic distribution on the River Tiefi near Cardigan, and the species appears to be declining within its historic stronghold on the River Thames although a population still survives near Goring.