By Jennifer Carter
Hidden in clusters of brambles and privet hedges, an obscure looking insect survives over 100 years after introduction.
Non-native, but not invasive, naturalised stick insects are rooted in the history of Cornwall’s exotic flora. In 19th century Cornwall, Treseder Nurseries, Truro, were one of the premier importers of tropical plants. They specialised in tree ferns,a sought-after species during a time when collecting ferns was a growing hobby.
What the collectors of the time didn’t know, was that along with these plants from New Zealand, came hitchhikers, whose legacy would still live on today.Cornwall is home to three naturalised species of stick insect: The Prickly Stick Insect, the Smooth Stick Insect, and the Unarmed Stick Insect, the one most common here in Falmouth. In the summer, people ask, what is this insect which has landed on their arm, or whether anybody has lost a pet. Most often, these are from breeding colonies which have made Cornwall their home.
Newly hatched stick insect nymphs are green in colour and usually 2-3cm long. Emerging in early April, they cling to the stems of bushes during the day, emerging only after dusk to feed on leaves under the safety of darkness. Adult stick insects vary largely in colour, from reddish brown, to green, and sometimes black. They stay almost completely still for most of their lives, moving only to feed, blending in perfectly with their surroundings.
Despite their accidental arrival, there are currently no concerns that they will have a negative impact on our native wildlife. With a high mortality rate and a plentiful food source, stick insects are not in competition with any native insects.
Thanks to those early Victorian era plant hunters, we can continue to enjoy their occasional appearances and be proud to share our home with such fascinating creatures.