Invasive non-native species are one of the biggest threats to Earth’s biodiversity, along with habitat destruction and climate change.
The ever-increasing transfer of goods and species between different countries, through global trade and human movement, is transporting plants and animals to locations they would not otherwise have been able to reach. If species are taken out of their natural habitats and introduced to new ones they may well not survive - but they could adapt and thrive. If this happens and they don't have natural predators or diseases to control their population, then they can get so out of control that they outcompete native species, dominate areas and damage ecosystems.
Are non-native species a problem?
In Britain there are around 2,000 established non-native species. Most of these are benign and pose no problems, with 10-12 new non-native species establishing themselves here each year. However, around 10-15% of these become invasive and have significant negative impacts on the environment, our economy and/or human health. The cost of these invasive non-native species (INNS) is estimated to be £1.8 billion per year and rising.
Read our issue of Wood Wise that looks at INNS management in UK woods, including rhododendron, Himalayan balsam and non-native deer.
Species alert: Asian hornet
An immediate problem everyone can help with is the Asian hornet, which was first spotted in the UK in Tetbury, Gloucestershire, in September 2016 and a new outbreak has just been reported in Woolacombe, North Devon. A rapid response network aims to eradicate individuals and nests as soon as they can, because they are deadly to honey bees and carry a nasty sting. If you see an Asian hornet it's important to report your sighting as soon as possible, with the location and a photograph (if you can), to email@example.com.
Here's how to tell the difference between our native European hornet, which is a valued part of our fauna, and the invasive Asian hornet.
European hornet, Vespa crabro: brown legs, black body with brown markings, mostly yellow abdomen with a brown upper section, yellow antennae, larger than the Asian hornet (30-35 mm), not generally aggressive.
Asian hornet, Vespa velutina: yellow-tipped legs, dark brown or black body, dark abdomen with yellow band on fourth segment, dark antennae, smaller than our native European hornet (25-30 mm), highly aggressive.
We can all do our bit
Key actions people can take to prevent INNS damaging our environment are to prevent their establishment, growth or spread, and increase knowledge and awareness. This can be done by:
finding out what INNS are in Britain and Ireland
checking plants are not INNS before buying them for gardens, ponds, etc
not allowing plants or animals that are not native to escape into the wild
cleaning sports and other equipment used in aquatic environments (such as for angling and kayaking)
responsibly removing and disposing of INNS from gardens and the wild.
A simple way to help increase overall understanding of where INNS are in the wild is to record where they are when you see them. If you are out walking, cycling, running, canoeing, or doing any other activity and you see an INNS, you can record its location using online recording schemes such as iRecord and PlantTracker, which also both have apps for mobile phones and tablets. This important knowledge then contributes to on the ground activity to eradicate or control those species.
The Woodland Trust has a number of volunteer working groups in various woods across the UK that you can get involved with. Working groups can be invaluable in helping us control INNS if they are becoming a problem in our woods, as well as carrying out many other worthwhile activities. Go to ourvolunteering sectionto find an opportunity near you.
There are also committed Local Action Groups (LAGs) that work specifically on tackling INNS across Britain. This network of groups and volunteers has been instrumental in the early identification, eradication and long-term management of many problem species, as well as helping to raise awareness of the issues they pose and the actions people can take to prevent their establishment and spread.
The list of LAGs can be found on the Government’s dedicatedGB Non-Native Species Secretariat websitealong with a whole host of valuable information on INNS, including a species information portal, online e-learning courses and species alerts.