Invasive non-native species FAQs

We have compiled a list of the most frequently asked questions regarding non-native invasive species. However, if you still need help to answer a query, please contact us.


What are non-native species?

Non-native species (NNS) are any animal or plant that have been introduced (deliberately or accidently) by human activity to an area in which they do not naturally occur. Some animals and plants may have been transported here a long time ago and be considered “naturalised”, but these are still non-native species. Others are native to some parts of the UK but not to other parts (for example native to the mainland but not all islands).

Invasive non-native species (INNS), sometimes referred to as ‘invasive alien species’, are those non-native species that have the ability to spread rapidly and become dominant in an area or ecosystem, causing adverse ecological, environmental and economic impacts. INNS can also affect our health.

It is important to remember that, while there are over 900 non-native species in Scotland, only a minority become invasive, but these few can have serious negative impacts.

It is illegal to release, plant or allow to spread any non-native species into the wild.

See the sections on 'the law' and your 'legal obligations on non-native species' for more information.

You can find out whether a plant or animal is outwith it’s native range on the SNH website.

What is the law on non-native species?

In Scotland NNS are covered by Section 14 of the Wildlife and Countryside Act 1981, which makes it an offence to:

  • release or allow to escape from captivity any animal to a place outwith its native range;
  • cause any animal outwith the control of any person to be at place outwith its native range;
  • plant or otherwise cause to grow any plant in the wild outwith its native range.

There are exceptions; for example, agricultural land, and private and public gardens are not generally considered to be ‘in the wild’, however areas such as woodlands, road verges or river corridors in the countryside are all considered as being ‘in the wild’.

Certain organisations have responsibilities for coordinating responses to invasive non native species; these are detailed in the Code of practice on non-native species published by the Scottish Government. SNH is identified as the overall lead coordinating body, and also has specific responsibility for terrestrial habitats; SEPA covers standing and running freshwater habitats, and Forestry Commission Scotland and Marine Scotland cover woodland and marine habitats, respectively.

In the case of terrestrial species the lead organisation is SNH, however SEPA continues to have a role in relation to consulting on the use of herbicides in or near watercourses, and is responsible for ensuring that knotweed waste is managed and disposed correctly.

The environmental legislation is designed to protect the natural environment and so cannot force someone to do anything about non-native species such as Japanese knotweed on their land unless it spreads ‘into the wild’; neither SNH nor SEPA have powers to act in a situation where the problem is one of a dispute between neighbours. Where a non-native species spreads onto a neighbours land and causes a nuisance, if it’s not possible to come to an amicable agreement with the neighbouring land owner, then advice from a solicitor on the potential use of civil proceedings would be the next course of action.

How can I identify non-native species?

If you work in the countryside, by rivers or the sea, it’s really useful to get to know how to recognise some high risk non-native species. A good place to start when it comes to aquatic habitats is the UKTAG high impactlist of invasive non-native species. All of these are present in the UK, but only some of them have been found in Scotland.

The GB non-native species secretariat websiteprovides identification sheets for many non-native species

Additional marine identification resources are available on the Marine Aliens website.

What should I do if I find a non-native species?

It is illegal to release, plant or allow to spread any non-native species into the wild. Don’t collect it or move it - leave it where it is!

See sections on the law and your legal obligations on non-native species for more information.

Non-native species or organisms can be easily spread and are not always apparent therefore good biosecurity practiceis essential.

If you find NNS where you are working, check your legal obligations.

If you want to report your finding, make a note of the date, the species, the number or quantity seen, and the national grid reference, and take a photo if possible as this may help verify the record.

You can report your finding to:

  • iRecordfor all species;
  • Plant Trackerphone app (free to download) to record some key terrestrial plant species into the iRecord database;
  • AquaInvadersphone app (free to download) to record some key freshwater aquatic species into the iRecord database;
  • Marine Aliens IIfor marine species;
  • Sealife Trackerphone app (free to download) to record some key marine species into the iRecord database.

If you have specific queries about what you’ve found, contact the habitat lead organisation directly, via the entry 'Who should I contact for information on non-native species?'.

Who should I contact for information on non-native species?

To report illegal activity such as fly-tipping of non-native plants (or garden waste that could contain them), or the trapping or moving of crayfish):

  • Police: if you witness an illegal activity happening, contact the police using the non-emergency 101 phone number, otherwise contact the relevant police forceand ask to speak to a Wildlife Crime Officer.
  • All types of fly-tipping, including the dumping of garden waste that could contain non-native species should also be reported to Dumb Dumpers.

General non-native species enquires and reports:

  • SEARS (Scottish Environment and Rural Services) 24/7 customer service number (08452 30 20 50) or email.

For habitat-specific enquiries, you can contact the habitat lead directly:

Species licensing enquiries:

  • SNH: Tel: 01463 725245 or email.

For release of most non-native species.

  • Marine Scotland: Tel: 0131 244 6236 or email.

For release of freshwater fish and marine species.

What are my legal obligations in relation to non-native species?

The main aim of the environmental legislation is to prevent the release of non-native species and, where that fails, to prevent them from becoming established.

If you own land, there is no legal requirement to control established non-native species but you are expected to take reasonable steps to prevent non-native species from escaping or spreading into the wild.

You should also avoid allowing NNS to spread from your land onto adjoining private land such as a garden; the owner of that land could take civil legal action against you as a nuisance neighbour.

It is illegal to release, plant or allow to spread any non-native species into the wild.

Non-native species or organisms can be easily spread and are not always apparent therefore good biosecurity practiceis essential.

The NetRegs websiteprovides free environmental guidance for small and medium-sized businesses in the UK. It will help you to understand what you need to do to comply with environmental law and protect the environment.

If you would like to release an animal or plant something ‘in the wild’ you need to make sure it is native to the area; if not you will require a licence from Scottish Natural Heritage. Their website gives advice on native range and details the species licensing procedure.

How can I make sure I don’t spread non-native species?

Adopt a precautionary approach – if in doubt don't release or plant anything in the wild until you have a clear understanding of the situation and your responsibilities (See the 'What are my legal obligations in relation to non-native species?' section). You can check the native range of a species on the SNH website. SNH can also advise on whether you require a licence to release or plant.

If you are planning any kind of controlled activity, for example engineering works on a watercourse, be aware that disturbance or movement of soils could cause the spread of a NNS.

More information is given in the ‘Do I need permission to remove or dispose of NNS or soils?’ section.

Non-native species or organisms can be easily spread and are not always apparent therefore good biosecurity practiceis essential.

If you take part in contact water activities such as yachting, canoeing or angling, on rivers, lochs or the coast, follow the advice on the Check Clean Dry pages. If you are organising a water sports event or gathering, there is a Scottish Event Biosecurity Guide and Risk Assessment to help you make sure your event doesn’t spread non-native species.

In the garden, follow the advice on the Be Plant Wise pages, which will help avoid spreading invasive pond plants.

You can also help efforts to prevent spread of NNS by reporting any you find in the wild (See the 'Who should I contact for information on non-native species?' section).

What should I do about non-native species in my garden?

Follow the advice on the Be Plant Wise pages, which will help avoid spreading invasive pond plants.

Plantlife provide useful publications on:

  • Gardening without harmful invasive plants
  • Landscaping without harmful invasive plants
  • Keeping ponds and aquaria without harmful invasive plants

More information is available for dealing with these plant species, in the following specific FAQ entries:

  • Japanese knotweed
  • Giant hogweed
  • Himalahan balsam

Where can I get funding to deal with invasive non-native species on my land?

On private land the landowner will generally bear the cost of removing NNS, although costs may be covered in part or full if the removal is being undertaken as part of a wider strategic (funded) project.

For example, The Rivers and Fishery Trusts of Scotlandhave developed biosecurity plans for many rivers across Scotland, and have secured funding for various control programmes. If you are located in one of their project areas you may be able to help their control efforts.

There are a number of funding sources that may consider contributing to strategic projects involving the control of invasive non-native species. These include:

For other potential sources of fundingsee the SNH external funding guidance.

Who is responsible for invasive non-native species on public land and along riverbanks?

The responsibility for NNS lies with the landowner or land manager. There is no legal requirement for a landowner to control established non-native species but they are expected to take reasonable steps to prevent non-native species from escaping or spreading into the wild.

If you manage land which benefits from a Single Farm Payment, check your responsibilities under cross compliancefor GAEC measure 18 ‘encroachment of unwanted vegetation’.

You can report sightings of NNS (See the 'What should I do if I find a non-native species?' section), and report the spread of NNS into the wild from privately owned land to the relevant habitat lead organisation (See the 'Who should I contact for information on non-native species?' section).

Do I need permission to spray non-native species with herbicide?

You must consult SEPA on the use of herbicides in or near watercourses; forms for non-aerial herbicide applications are available on the SEARS website, or you can contact your local SEPA Operations Team before you start work.

The only herbicide licensed for use in or near water is glyphosate.

All plant protection products, such as herbicides, are licensed by the Health and Safety Executive. They can provide more information on choice and appropriate use of licensed products.

HSE requires that anyone who uses a professional pesticide product must hold a Certificate of Competence if:

  • They were born after 31 December 1964; or
  • Are providing a commercial service e.g. contractors or anyone spraying on land that is not his or his employers.

If amateur products are used outside the home garden situation, either in a commercial business or by volunteers, then the user needs to be aware of Questions 8,9 and 10 on the HSE pesticides FAQ page.

It is the product itself that will define whether it is for professional or amateur use. If you are unsure, check the HSE pesticides register. Note that this list is frequently updated so you should always check before starting a new project to ensure the product you are planning to use is still appropriately licensed.

Do I need permission to remove or dispose of NNS or soils?

This information is particularly relevant to developers or contractors.

Control of any plants with herbicides requires consultation with SEPA if working in or near watercourses (See the 'Who should I contact for information on non-native species?' section).

Advice and guidance on the safe use, control and disposal of NNS plants and contaminated soil is given on the NetRegs website.

If in doubt, contact your local SEPA Operations Team for information on transportation or disposal of contaminated soils before you start work.

Non-native species that you might come across

Some of the better known invasive non-native species that you may be likely to come across, particularly in rivers or on river banks are:

  • Japanese knotweed
  • Giant hogweed
  • Himalayan balsam
  • North American signal crayfish

Japanese knotweed

You can get help in identifying this terrestrial plant from the identification guides on the GB non-native species secretariat website.

If this species already occurs on your land, there is no legal requirement to control it but you are expected to take reasonable steps to prevent it from escaping or spreading into the wild. You should also avoid allowing it to spread from your land onto adjoining private land such as a garden; the owner of that land could take civil legal action against you as a nuisance neighbour.

You can report sightings of NNS (See the 'What should I do if I find a non-native species?' section). If you see this species spreading into the wild from private land, you can report it to the relevant habitat lead organisation (See the 'Who should I contact for information on non-native species?' section).

Reporting an illegal activity

  • Police: if you witness an illegal activity happening (ie the release, planting or allowing to spread of any non-native species into the wild), contact the police using the non-emergency 101 phone number, otherwise contact the relevant police forceand ask to speak to a Wildlife Crime Officer.
  • All types of fly-tipping, including the dumping of garden waste that could contain non-native species should also be reported to Dumb Dumpers.

Japanese knotweed and householders

In recent years, Japanese knotweed has caused some problems in the residential housing market, as concerns about the damaging effects of the plant have made some lenders reluctant to provide mortgages for affected properties. The Council of Mortgage Lenders, the Royal Institution of Chartered Surveyors and the Property Care Association have been working together to help address this problem.

Remember that if you have Japanese knotweed on your land, you could be affecting adjacent landowners, so make sure that you are aware of your responsibilities (See the 'What are my legal obligations in relation to non-native species?' section).

As a householder or landowner, there is action you can take on your land to control Japanese knotweed.

The Royal Horticultural Societyprovides advice for gardeners, and the Centre for Ecology and Hydrologyhave produced a useful factsheet.

If you carry out any control of this species or carry out any work on areas containing Japanese knotweed, check that you have the correct permissions before starting work (See the 'Do I need permission to remove or dispose of NNS or soils?' section).

Giant hogweed

Beware! The sap of giant hogweed can cause painful burning and blistering on contact with human skin. This effect is further increased by exposure to sunlight. Wash skin with soap and water as soon as possible after exposure. Seek medical advice after contact with giant hogweed sap, especially after contact with the eyes.

You can get help in identifying this terrestrial plant from the identification guides on the GB non-native species secretariat website.

If this species already occurs on your land, there is no legal requirement to control it but you are expected to take reasonable steps to prevent it from escaping spreading into the wild. You should also avoid allowing it to spread from your land onto adjoining private land such as a garden; the owner of that land could take civil legal action against you as a nuisance neighbour.

You can report sightings of NNS (See the 'What should I do if I find a non-native species?' section). If you see this species spreading into the wild from private land, you can report it to the relevant habitat lead organisation (See the 'Who should I contact for information on non-native species?' section).

Reporting an illegal activity

  • Police: if you witness an illegal activity happening (ie the release, planting or allowing to spread of any non-native species into the wild), contact the police using the non-emergency 101 phone number, otherwise contact the relevant police forceand ask to speak to a Wildlife Crime Officer.
  • All types of fly-tipping, including the dumping of garden waste that could contain non-native species should also be reported to Dumb Dumpers.

Giant hogweed and householders

As a householder or landowner, there is action you can take on your land to control giant hogweed.

The Royal Horticultural Societyprovides advice for gardeners, and the Centre for Ecology and Hydrologyhave produced a useful factsheet.

You can also download for free the Giant hogweed best practice manual (Nielsen, C., H.P. Ravn, W. Nentwig and M. Wade (eds.), 2005. The Giant Hogweed Best Practice Manual. Guidelines forthe management and control of an invasive weed in Europe. Forest & Landscape Denmark, Hoersholm, 44 pp.)

If you carry out any control of this species or carry out any work on areas containing giant hogweed, check that you have the correct permissions before starting work (See the 'Do I need permission to remove or dispose of NNS or soils?' section).

Himalayan balsam

You can get help in identifying this terrestrial plant from the identification guides on the GB non-native species secretariat website.

If this species already occurs on your land, there is no legal requirement to control it but you are expected to take reasonable steps to prevent it from escaping spreading into the wild. You should also avoid allowing it to spread from your land onto adjoining private land such as a garden; the owner of that land could take civil legal action against you as a nuisance neighbour.

You can report sightings of NNS (See the 'What should I do if I find a non-native species?' section). If you see this species spreading into the wild from private land, you can report it to the relevant habitat lead organisation (See the 'Who should I contact for information on non-native species?' section).

Reporting an illegal activity

  • Police: if you witness an illegal activity happening (ie the release, planting or allowing to spread of any non-native species into the wild), contact the police using the non-emergency 101 phone number, otherwise contact the relevant police forceand ask to speak to a Wildlife Crime Officer.
  • All types of fly-tipping, including the dumping of garden waste that could contain non-native species should also be reported to Dumb Dumpers.

Himalayan balsam and householders

As a householder or landowner, there is action you can take on your land to control Himalayan balsam.

The Royal Horticultural Societyprovides advice for gardeners, and the Centre for Ecology and Hydrologyhave produced a useful factsheet.

If you carry out any control of this species or carry out any work on areas containing Himalayan balsam, check that you have the correct permissions before starting work (See the 'Do I need permission to remove or dispose of NNS or soils?' section).

North American signal crayfish

New: North American signal crayfish FAQ

You can get help in identifying this aquatic animal from the identification guides on the GB non-native species secretariat website.

The North American Signal crayfish (Pacifastacus leniusculus) is a lobster-like invertebrate which can grow in excess of 16cm long and is found in freshwater habitats. They have an adverse impact on running and standing waters through predation or displacement of native species, and their burrows can destabilise the banks of rivers and ponds. More information on their ecology and on work going on across Scotland can be found on the SNH website.

Once they have been introduced to a watercourse, it is very unlikely that Signal crayfish can be eradicated. There have been a small number of trial eradications from small ponds, but this cannot be attempted in larger waterbodies where the chemical treatments are not effective.

You can help prevent the spread of non-native crayfish by following the advice in the Check Clean Dry campaign and by reporting any you find (See the 'Who should I contact for information on non-native species?' section).

It is illegal to possess a live crayfish in Scotland.

If you catch one accidentally, do not take it away alive. Kill it humanely by placing it on a hard surface, then hit it with a single lethal blow with a heavy or hard object, or crush it with a single action.

If you need to carry out any work on areas containing North American Signal crayfish, check that you are aware of your responsibilities and how to prevent spread (See the 'How can I make sure I don’t spread non-native species?' section).

If you want to trap Signal crayfish in Scotland you need to request a licence from the Scottish Natural Heritage licensing team.

They can be contacted by email or telephone: 01463 725 246/245.

SNH only issue crayfish licences under exceptional circumstances because the risk of encouraging their spread is so great. They only issue licences for survey work to monitor the distribution and spread of signal crayfish in Scotland. They don’t issue licences for the purpose of catching crayfish to eat because this creates incentives for people to move them to new areas.

Some people promote the idea that trapping for food can help the conservation effort. Although trapping may appear a useful aid to getting rid of them it can actually make the problem far worse as traps tend to favour larger male individuals, removing natural predation within the population (the big ones cannibalise the small ones and can help keep the population in check) so leaving a younger, more readily reproducing population that spreads more quickly.

Reporting an illegal activity

  • Police: if you witness an illegal activity happening (ie the trapping or moving of crayfish), contact the police using the non-emergency 101 phone number, otherwise contact the relevant police forceand ask to speak to a Wildlife Crime Officer.

Links

  • The GB non-native species secretariat websitehosts a wealth of information on NNS including identification, reporting and species alerts. If you are running a project working on NNS, you can register your group and/or project on their website and share your experiences.
  • The UKTAG websitegives more information on how INNS are included in classification of rivers, lochs and estuaries.
  • The Scottish Government websiteprovides more information on legislation.
  • The SNH website has a comprehensive section on non-native species
  • The SEPA website has a basic overview of INNS and FAQs.
  • The Rivers and Fishery Trusts of Scotlandhave developed biosecurity plans for many parts of Scotland. If you are located in one of their project areas you may be able to help their control efforts.
  • The Parliamentary Office of Science and Technology has recently published the following POSTnoteon non-native plants.