IUCN Red Listed New Zealand Species
The IUCN Red List Categories and Criteria are intended to be an easily and widely understood system for classifying species at high risk of global extinction. The general aim of the system is to provide an explicit, objective framework for the classification of the broadest range of species according to their extinction risk. However, while the Red List may focus attention on those taxa at the highest risk, it is not the sole means of setting priorities for conservation measures for their protection.
Categories
For full details of Red List catagories and criteria for placing a species
see the 2006 IUCN Red List Categories and Criteria (v.3.1)
EXTINCT (EX)
A taxon is Extinct when there is no reasonable doubt that the last individual
has died. A taxon is presumed Extinct when exhaustive surveys in known
and/or expected habitat, at appropriate times (diurnal, seasonal, annual),
throughout its historic range have failed to record an individual.
Surveys should be over a time frame appropriate to the taxon's life
cycle and life form.
EXTINCT IN THE WILD (EW)
A taxon is Extinct in the Wild when it is known only to survive in cultivation,
in captivity or as a naturalized population (or populations) well outside
the past range. A taxon is presumed Extinct in the Wild when exhaustive
surveys in known and/or expected habitat, at appropriate times (diurnal,
seasonal, annual), throughout its historic range have failed to record
an individual. Surveys should be over a time frame appropriate to the
taxon's life cycle and life form.
CRITICALLY ENDANGERED (CR)
A taxon is Critically Endangered when the best available evidence indicates
that it meets any of the criteria A to E for Critically Endangered
(see Section V), and it is therefore considered to be facing an extremely
high risk of extinction in the wild.
ENDANGERED (EN)
A taxon is Endangered when the best available evidence indicates that
it meets any of the criteria A to E for Endangered (see Section V),
and it is therefore considered to be facing a very high risk of extinction
in the wild.
VULNERABLE (VU)
A taxon is Vulnerable when the best available evidence indicates that
it meets any of the criteria A to E for Vulnerable (see Section V),
and it is therefore considered to be facing a high risk of extinction
in the wild.
NEAR THREATENED (NT)
A taxon is Near Threatened when it has been evaluated against the criteria
but does not qualify for Critically Endangered, Endangered or Vulnerable
now, but is close to qualifying for or is likely to qualify for a threatened
category in the near future.
LEAST CONCERN (LC)
A taxon is Least Concern when it has been evaluated against the criteria
and does not qualify for Critically Endangered, Endangered, Vulnerable
or Near Threatened. Widespread and abundant taxa are included in this
category.
DATA DEFICIENT (DD)
A taxon is Data Deficient when there is inadequate information to make
a direct, or indirect, assessment of its risk of extinction based on
its distribution and/or population status. A taxon in this category
may be well studied, and its biology well known, but appropriate data
on abundance and/or distribution are lacking. Data Deficient is therefore
not a category of threat. Listing of taxa in this category indicates
that more information is required and acknowledges the possibility
that future research will show that threatened classification is appropriate.
It is important to make positive use of whatever data are available.
In many cases great care should be exercised in choosing between DD
and a threatened status. If the range of a taxon is suspected to be
relatively circumscribed, and a considerable period of time has elapsed
since the last record of the taxon, threatened status may well be justified.
