Hansard

The reaction of many people to hearing that the Scottish Parliament is spending time debating a strategy on invasive non-native species might well be to ask, "Why?" People do not overtly recognise the issue but, on further examination, most would have some knowledge and awareness of problematic invasive non-native species, such as grey squirrels, giant hogweed or North American signal crayfish. However, one issue that may not be as obvious is the cost to various agencies of trying to control invasive species, which runs into millions of pounds in the UK, as the cabinet secretary said. On plant health alone, £450,000 is spent in Scotland each year and the Department for Environment, Food and Rural Affairs spends £10 million throughout the UK. British Waterways spends £1 million every year dealing with problems that are caused by just 12 non-native species that threaten native wildlife in our rivers, including red-eared terrapins, zander, mink, signal crayfish, giant hogweed, floating pennywort and Japanese knotweed. It is estimated that non-native species cost the Scottish economy at least £200 million annually, as Mr Lochhead said.

There are strong economic as well as environmental reasons to develop a strategy for prevention and control of such species. It makes sense for the strategy to be uniform throughout the UK, because the British coast provides a natural barrier to many invasive species. Therefore, the joint strategy that has been signed off by environment ministers from the UK Government, the Scottish Government and the Welsh Assembly Government is welcome. Invasive non-native species of flora and fauna are considered to be the second-biggest threat to biodiversity after habitat destruction and are a particular threat to fragile ecosystems such as are on the islands.

Many species that are currently invasive were imported many decades ago and were not invasive at the time. Climate change can alter the viability of a species and that of those that are in competition with it. One challenge is to predict which species have the potential to become invasive and which require monitoring for changes in risk. Prevention and early intervention are better solutions than trying to eradicate or control a species once it has become invasive. In the longer term, it is cheaper and more effective to invest in research and the scientific basis for risk assessment than it is to tackle the problem once it has become established.

The invasive non-native species strategy arose from a comprehensive policy review in 2003 and a consultation that was published at the end of February 2008. The strategy is based on the three-stage approach that was agreed in 2002 by the parties to the "Convention on Biological Diversity". The first stage consists of raising awareness of risks and understanding of impacts to prevent the introduction of potentially invasive species; the second stage is to improve early detection and rapid response to introductions before problems escalate; and the third is to develop longer-term control programmes that are based on sound science. The aims of the strategy are to minimise risk and reduce the negative impact of non-native invasive species by improved co-ordination of the responsibilities of Government and other agencies; to increase public awareness of the problem and encourage behaviour that reduces the risk of the introduction of more such species; and to draw up contingency plans, should a species become invasive for whatever reason.

The implementation of the strategy will be overseen by the Great Britain non-native species programme board, supported by the Non-native Species Secretariat. A UK consultation has also been launched on possible revisions to section 9 of the Wildlife and Countryside Act 1981 to add non-native species to the list of species that it is an offence to release into the wild. The European Commission is developing proposals for a Europe-wide strategy. The Government's motion is correct to identify that the UK and the devolved legislatures in Scotland and Wales are at the forefront of tackling the issue in Europe.

Many of the species have been introduced through human ignorance. The general public need to be aware of the possible consequences of bringing plants into the country or of releasing unwanted pets into the natural environment. Red-eared terrapins became popular during the "Teenage Mutant Ninja Turtles" craze of the 1990s. I had young children, so I remember it well. Many of those terrapins ended up in the wild when their young owners' interest in them waned. American mink escaped or were released from fur farms during the 1930s and are now widespread throughout Scotland and can cause major destruction to seabird colonies. Signal crayfish were introduced for aquaculture in the 1970s, but they spread and now threaten native crayfish through transmission of a fatal disease to which the non-native species is immune. In addition, they burrow into water banks in order to nest, causing damage to the habitat of other creatures, and they compete with other species such as trout and salmon by eating their food and their young.

The most famous non-native invasive species in Scotland is perhaps the grey squirrel, which was introduced in the late 19th century. It damages deciduous trees by stripping their bark and has caused the rapid decline of the red squirrel population through competition for food, and—like the signal crayfish—transmission of a fatal disease to which it is far less susceptible. On a more positive note, there is recent evidence that the reds might be developing some immunity to squirrel pox, which is certainly helpful.

The giant hogweed was—oddly enough—introduced as a decorative plant, but it has invaded river banks and is harmful to humans as well as to other plant species.

The existing measures to exert control over invasive non-native species are contained primarily in the Wildlife and Countryside Act 1981 and the Nature Conservation (Scotland) Act 2004, although other legislation such as the European Union habitats directive and birds directive, and the Convention on Biological Diversity, are also relevant.

RSPB Scotland, in its briefing for this debate, contends that the legislative framework is not coherent, and that very few prosecutions have been brought. The Labour amendment—which I am pleased the Government will agree to—asks ministers to examine the current legislation to assess whether it acts, as has been suggested, in a piecemeal fashion, and whether it could be strengthened.

We will support the Liberal Democrat amendment, which makes it explicit that action is not solely the responsibility of Government and Government agencies. That is implicit in the Government motion and in the strategy, but there is no harm in making it clear in the amended motion that will, I hope, be passed by Parliament this afternoon.

Many local organisations play a vital role in identifying species that are, or are becoming, invasive, and preventing their spread. The Wildfowl and Wetlands Trust in London is fighting an on-going battle against the azolla fern, which could choke the wetlands and destroy the habitat of the vast range of wildlife that is dependent on them.

Angling organisations around Loch Ken in Galloway have been at the forefront of the battle to control the signal crayfish. Controlling and—more importantly—preventing the spread of non-native invasive species is everybody's responsibility.

I move amendment S3M-2777.2, to insert at end:

"and asks the Scottish Government to review existing legislation and report back to the Parliament on whether it considers that current legislation requires to be strengthened to ensure that the issue of non-native species is addressed more effectively."