Exotic Aquatic Organisms - International Development Research ...
Exotic Aquatic Organisms - International Development Research ...
Exotic Aquatic Organisms - International Development Research ...
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Appendix I<br />
Definitions of <strong>Exotic</strong>s<br />
The 1986 ASFA Thesaurus gives a "scope note" or "rough definition" of introduced species<br />
as "Establishment in a new geographical area of a species by migration or artificial<br />
transportation."<br />
The same Thesaurus gives a "rough definition" of transplantation as "Artificial" introduction<br />
of organisms into habitats where they do not occur naturally.<br />
The ASFA Thesaurus does not use the word exotic.<br />
Welcomme, R.L. 1988. (<strong>International</strong> introductions of inland aquatic species. FAO Tech.<br />
Pap. 294, 318 p.) follows the 1987 EIFAC Code of Practice, which used these definitions.<br />
Introduced species (includes both non-indigenous and exotic species): Any species<br />
intentionally or accidentally transported and released by man into an environment outside<br />
its present range.<br />
Transferred species (includes transplanted species): Any species intentionally or<br />
accidentally transported and released within its present range.<br />
"Transfers are usually intended to support stressed populations, introduce genetic<br />
diversity into a stock or to reestablish a species whose stocks have failed locally.<br />
Introductions are intended to insert a totally new element into the fauna".<br />
Welcomme commented, "One reservation is made with respect to these definitions in that a<br />
species is considered to have been introduced to a country once it has crossed national<br />
boundaries. This means that species are included in the listing if they are transported into a<br />
country as part of current commercial practice for food or ornament and not for stocking into<br />
natural environments. Experience has shown that even such species may have impacts through<br />
the release of pathogens or through escape."<br />
Marine species: Any aquatic species that does not spend its entire life cycle in fresh<br />
water.<br />
Introduced species (= non-indigenous species; includes both non-indigenous and exotic<br />
species): Any species intentionally or accidentally transported and released by man into<br />
an environment outside its present range.<br />
Transferred species (= transplanted species): Any species intentionally or accidentally<br />
transported and released within its present range.<br />
Quarantined species: Any species held in a confined or enclosed system that is designed<br />
to prevent any possibility of the release of the species, or any of its diseases or any other<br />
associated organisms into the environment.<br />
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