Definition of terms

Non-native species

The term 'non-native species' is used throughout this website and is the equivalent of 'alien species' as used by the Convention on Biological Diversity (external link) (CBD).  It refers to a species, subspecies or lower taxon, introduced (i.e. by human action) outside its natural past or present distribution; includes any part, gametes, seeds, eggs, or propagules of such species that might survive and subsequently reproduce.  Non-native species covered by this website include all fauna and flora with the exception of genetically modified organisms (GMOs), bacteria and viruses.
Invasive non-native species

An invasive non-native species is any non-native animal or plant that has the ability to spread causing damage to the environment, the economy, our health and the way we live.
The precautionary principle

The precautionary principle describes a way of approaching policy and decision making in the absence of full scientific certainty.  It is discussed in both the Rio Declaration and Convention on Biological Diversity: 

Rio Declaration Principle 15:
“In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. 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.”

CBD preamble:
“where there is a threat of significant reduction or loss of biological diversity, lack of full scientific certainty should not be used as a reason for postponing measures to avoid or minimize such a threat.”

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