Nonnative Species

1
Non-native Species

• Paul Walton
• RSPB Scotland

2
The Alien Issue

• Counter-intuitive more means less?
• Involves thinking globally
• Is about biodiversity but whats that?
• Experts squabble over whether there is a
  problem
• Can look like xenophobia in disguise.
• Involves restricting movement even trade
• Involves killing animals - attractive ones.
• Is difficult to articulate.

3

• . Many non-native species have been
  deliberately introduced into Great Britain where
  they contribute to economic and social
  well-being. Many other species have been
  introduced accidentally. Most, such as horse
  chestnut and little owl, are benign or make
  valuable contributions to Britains natural
  heritage.
• Paragraph 1.1,
• GB Invasive Non-native Species Framework
  consultation.

4
x
Actual Global Total gt
x
Predicted Global Total gt
Vitousec, PM et al (1997) New Zealand Journal of
Ecology 21 (1) 1-16. Analysis by A. Launer,
Stanford University, reproduced with permission.
5
What is needed?

• Prevention
• Detection
• Mitigation
• Restoration
• .. in balance

6
and

• Under Guiding Principle 1 of the Convention on
  Biological Diversity
• Activity with respect to non-native species
  should take, as far as is practical, a
  precautionary approach.

7
Legislation

• WCA Sect 14 hardly ever used almost never
  successfully.
• Schedule 9 lists species already established
  stable door.
• Approach to regulating releases is piecemeal

8
Legislation we need

• Define the terms native, non-native, etc to
  reflect that a native to one part Great Britain
  but not to another is as likely to be damaging as
  species from overseas.
• Prohibit release of broad taxa with named
  exceptions
•  
• Introduce a duty on ministers to require action
  to control, contain or eradicate damaging
  species.
•  
• Introduce a power to allow the imposition of a
  restoration order upon conviction of an offence
  under s14 - the polluter pays.

9
Risk Assessment

• Predictability similar to Earthquakes
• Individual events inherently RANDOM
• BUT
• Strong taxonomic and geographic patterns evident
• Risk MINIMISATION is way fwd
• Invasion STAGE must be considered
• Surviving transport, gaining foothold,
  establishment, spread, ecol impact, human impact.

10
Risk Assessment

• Not perfect, but.
• Weed Risk Assessment, Australia
• 49 questions on known species attributes
• palatability, distribution, reproduction
  etc.
• Calibrated using 370 known non-natives, and
  acceptance/rejection criteria then set.
• A modified version tested for Pacific non-native
  plants predicted 85 of pest species.

11
Public attitudes to eradication in
ScotlandBremner et al Stirling University, in
prep.

• Sample 553 randomly selected from phone book.
• Agree control/eradication when NNS threaten
  native wildlife
• 78
• Agree when native wildlife is rare
• 84 (2 disagree)
• Eradicate all non-natives?
• 45
• Have heard of Uist hedgehog issue
• 19 (over 70 support control, 90 who had
  heard of issue)
• Method important poisoning and shooting
  unpopular.
• Strong majority in favour of control and
  eradication of damaging non-native species.

12
Scope

• In biodiversity terms, by far the greatest value
  would be achieved by including UK Overseas
  Territories
• Many of these are highly vulnerable islands w
  unique endemic species.
• The strategy is the best opportunity to address
  urgent NNS issues in these areas.

13

• The Tens Rule
• 10 species establish 10 of these spread
  10 of these cause problems.
• So only 1 in 1000 species is a problem why the
  fuss?

14
The Tens Rule

• BUT.
• Quantitatively, not accurate.
• The 10 covered 5-20 4 fold error 4x4x464x.
• 2005 study European vertebrates in USA
• gt 50 establish and gt 50 spread.
• Qualitatively, not comprehensive.
• The tens rule does not convey severity of impact.
• It does not convey our inability to predict
  invaders.
• Tens rule has been misapplied and has
• perhaps outlived its usefulness