1.   PLAUSIBLE HYPOTHESIS OR SCIENTIFIC CERTAINTY: PROTECTING BIODIVERSITY FROM INVASIVE ALIEN SPECIES IN AN ERA OF CLIMATE CHANGE

2. 1. The Problem
2. Precaution or Scientific Certainty?
3. The Trigger for Measures
4. Will Measures Pass WTO Tests?
5. Australia’s Weed Risk Assessment
6. Conclusion

3. climate change will intensify the dangers posed by IAS.
1. 1The Problem: Climate Change, Biodiversity and Invasive Alien Species
Invasive alien species (IAS) are alien species that threaten ecosystems, habitats or other species.
climate change will intensify the dangers posed by IAS.

5. Alan Pounds
“Disease is the bullet killing [species], but climate change is pulling the trigger,"

6. 1.2 The Problem: Uncertainty
Regulators face constant challenges in dealing with uncertainty
Uncertainty can stem from lack of quantity of scientific evidence or from plentiful evidence that is inconclusive.

7. The only certainty in life is uncertainty
Regulators have three choices:
reduce the level of uncertainty;
reduce the effects of uncertainty;
use a combination of these methods.
In practice, policy instruments recommend that decision-makers adopt regimes more closely aligned to the third alternative.
The only certainty in life is uncertainty

8. 2. Precaution or Scientific Certainty?
2.1 Precautionary Approach
Principle 15 of the Rio Declaration :
Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.

9. 2.2 Rules of WTO
Agreement on the Application of Sanitary and Phytosanitary Measures (SPS Agreement).
Two-staged approach to quarantine measures:
Countries determine appropriate level of protection or ALOP
Countries implement operational provisions to give effect to ALOP
Measures must be based on international standards (eg those set by OIE or IPPC) or be based on risk assessment

10. 3. The Trigger for Measures
TRADE
Prevent states using alien species to create unnecessary trade barriers; and in particular stop states asserting that lack of knowledge should permit them to implement measures more trade-restrictive than necessary.
ENVIRONMENT
Regulators should be at liberty to prevent entry of potentially invasive species, even in the absence of conclusive scientific certainty of the invasive qualities of these species.

11. A Relational Approach to Uncertainty?
Address uncertainty from perspective of all stakeholders
Understand that solutions do not solely consist of eliminating uncertainty
What, then is the threshold for implementation of measures?

12. 3. 2 Plausible Hypotheses?
The concept of ‘plausibility’ describes a proposition that remains persuasive until an alternative is shown to be more credible.
creates a presumption.
Regulators need some evidence to justify measures, even though measures not underpinned by full scientific certainty
Identifies the stage where precautionary approach can become operational.

13. 4. What of WTO Tests?

14. European Communities – Measures Concerning Meat and Meat Products (Hormones), (EC – Hormones)
4.1 Scientific Certainty and the WTO
very detailed studies supported by large volumes of conclusive evidence
analyses of the invasive qualities of every IAS in question, accompanied by information on the impact of climate change on each IAS.

15. Measures need a rational relationship to scientific evidence
4.2 Heads I Win, Tails You Lose- inconclusive material
UNCERTAINITY
Under Article 5.7 temporary measures only justified if scientific evidence is ‘insufficient’
Article 2.2 SPS Agreement
Measures need a rational relationship to scientific evidence
where the evidence is plentiful but inconclusive it must undergo a risk assessment
Inconclusive evidence cannot form the basis of measures

16. 5. Australia’s Weed Risk Assessment
a set of questions about:
plant’s distribution;
whether the plant is toxic to animals;
whether it hybridises naturally; and
information about its dispersal.
minimum number of questions must be answered.
The answers are scored: accept, reject, or further evaluate.
Further evaluate = deny entry until additional information is obtained ( ‘grey list)’.

17. Conclusion
International community needs to reconsider approaches to uncertainty in international instruments.