Aquatic ecosystems are complex, and it is very
difficult to predict how an introduced non-native species will
affect ecosystem structure and function in a novel environment.
Many introductions of non-native species go unnoticed, but
species that prove invasive can have devastating impacts.
Therefore, a precautionary, risk-based approach is considered
appropriate in relation to the keeping and release of non-native
The assessment of risks must be evidence-based, providing
environmental managers and government with a balanced, up-to-date
summary of available information on the species in question. This
allows them to make informed decisions about the potential benefits
and adverse impacts of a non-native species.
The risk-analysis process involves the use of decision-support
tools to identify and assess the hazards posed by non-native
species. Similarly, decision-support tools are also used in the
evaluation of the potential environmental impacts that would be
associated with each management option (e.g. eradication, control,
It is therefore vital to understand the environmental biology
and interactions of non-native species with native species, in
particular those of conservation interest. Because of the
increasing amount of global trade, research on the risks and
impacts of non-native species requires collaboration at local,
national and international levels.
NATO Collaborative Linkage Network
Risks associated with the translocation of fish species between
NATO countries, an activity undertaken for numerous decades, have
received increased attention in recent years. Prediction of which
species could be translocated, either intentionally or not, is
central to risk assessment.
These predictions have relied upon the analysis of life history,
physiological and behavioural traits, assessments of transmission
pathways and past establishment success. Life-history traits are
among the most variable but also most useful indicators to identify
potentially invasive fish species.
The scientific objectives of the Collaborative Linkage Network
(CLN) are to:
- assess variability of life-history traits in selected North
American fish species established in Europe and European species
established in North America
- identify and/or develop life-history indices of use in
predicting establishment success
- test the predictive power of these indices within a
The range of topics now addressed by the CLN including work on
non-native invertebrates and a wider examination of non-native
fish impacts. As such, the collaborative activities and outcomes of
the CLN encompass the environmental biology of non-native
fishes and invertebrates, their relevance to predicting and
assessing biological invasions, and their impacts.
The CLN places emphasis on life-history variations, in
particular with regard to the potential influence of climate change
factors - principally temperature and hydrological
For more information about the CLN, the network partners and
their scientific outputs, contact Gordon Copp.