Non-native species


Invasive Alien Afternoon II - 20 March 2013

No need to book, just drop in anytime between 1pm and 7pm, Eaton Vale Activity Centre, Church Lane, Eaton, Norwich, NR4 6NN.

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About us

NNIS Logo The Norfolk Non-native Species Initiative was launched in 2008 to promote the prevention, control and eradication of invasive, alien species. It seeks to do this by:

  • Collating and monitoring data on the distribution and spread of non-native species in the county;
  • Developing action plans to address the species of most urgent concern;
  • Facilitating control and eradication projects at high priority sites; and
  • Promoting awareness of the risks and impacts associated with non-native species.

The Initiative has been established under the umbrella of the Norfolk Biodiversity Partnership and works through a stakeholders' forum comprised of representatives from over 20 organisations. It is financially supported by the Broads Authority, the Environment Agency, Natural England, Norfolk County Council and the Water Management Alliance.

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Why do invasive non-native species matter?

Himalayan balsam
Himalayan balsam
(Photo credit: Mary Pipes)
Invasive non-native species pose one of the most serious threats to biodiversity worldwide, second only to habitat loss. The economic impacts of these species can also be severe. Indeed, it has been estimated that damage caused by invasive species amounts to almost five percent of the world economy! In Britain alone, these species cost our economy approximately £2 billion a year.

A massive increase in global trade and travel are two of the main factors contributing to the spread of species outside their natural range. As a nation with a long history of seafaring, England also has a correspondingly long history of species introduction. It is important to remember that the vast majority of these introductions have not had significant negative effects. In 1986, it was estimated that out of all the non-native species established in the UK, only 8.5% of vertebrates, 6.5% of insects and 13.6% of plants can be considered as pests. Indeed, many of our most valuable crop species, such as wheat Triticum aestivum and potatoes Solanum tuberosum, are 'non-native'. Other charismatic species, such as the little owl Athene noctua and horse chestnut Aesculus hippocastanum, are now widely embraced as a part of UK biodiversity.

Those non-native species that do have a significant negative impact are termed 'invasive'.

How do we deal with invasive non-native species?

The Convention on Biological Diversity (CBD) encourages a three-stage hierarchical approach to the management of invasive non-native species:

The first stage, prevention, is widely considered to be the most efficient and cost effective management approach.

The Invasive Non-Native Species Framework Strategy for Great BritainSurveillance and monitoring comprise the second stage. It is impossible to prevent all non-native species from establishment. In these cases, it is essential that newly introduced species be detected early and other pre-existing potentially invasive species be monitored to assess whether their status is changing. Historically, non-native species have been under-recorded and the time intervals between surveys too long to detect a change of status in these species early enough for pro-active management.

The final stage outlines action against species with an established population (or populations). In this situation, eradication is the most desirable, but often also the most difficult, management strategy. If eradication is not feasible then containment, control and mitigation are all alternative management options.

In May 2008, 'The Invasive Non-Native Species Framework Strategy for Great Britain' was published. This Strategy sets out the high-level framework for Government policy dealing with invasive non-native species and is amongst the first of its kind in Europe, putting the UK at the forefront of policy development in this area. The Norfolk Non-native Species Initiative will play a key role in translating this high-level framework into projects producing tangible results 'on the ground' in the county. To view the full Framework Strategy, please click here.

What is being done in Norfolk?

Norfolk is a county rich in biodiversity. We are surrounded by a wealth of plant and animal life. Whilst this has great benefits, it does mean that the county is more vulnerable than most to the impacts of invasive alien species. To address the threat of these species, the Norfolk Biodiversity Partnership has taken the lead by launching the Norfolk Non-native Species Initiative.

Myocastor coypus
(Photo Credit: J. Patrick Fischer)

We have a heritage of pro-active management of invasive non-native species in Norfolk. During the 1980s, coypu Myocastor coypus was successfully eradicated from the area. The species established a feral population during the 1920s (following escape from fur farms). Coypu causes damage to agricultural crops and undermines river banks, so the economic  impacts of this species are clear.

Coypu was also causing damage to biodiversity through intensive grazing of native plant species. Despite the high cost of this eradication operation, recent cost-benefit analysis has provided evidence that this pro-active approach makes economic sense in the long run. In Italy, where ongoing permanent control of the species is in place, management has cost €14 million over only six years. This is compared with the cost of the eradication in Britain (East Anglia formerly held the only UK population of coypu) which cost only €5 million spread over 11 years. The species also continues to expand its range in Italy, increasing damage and economic losses at a national scale.