Data Deficient

Conservation status by IUCN Red List category
Extinct
Extinct (EX) Extinct in the Wild (EW)	(list) (list)
Threatened
Critically Endangered (CR) Endangered (EN) Vulnerable (VU)	(list) (list) (list)
Lower Risk
Near Threatened (NT) Conservation Dependent (CD) Least Concern (LC)	(list) (list)
Other categories
Data Deficient (DD) Not Evaluated (NE)	(list)
Related topics International Union for the Conservation of Nature (IUCN) IUCN Red List Lists of organisms by population

A data deficient (DD) species is one which has been categorised by the International Union for Conservation of Nature as offering insufficient information for a proper assessment of conservation status to be made. This does not necessarily indicate that the species has not been extensively studied; but it does indicate that little or no information is available on the abundance and distribution of the species.

The IUCN recommends that care be taken to avoid classing species as "data deficient" when the absence of records may indicate dangerously low abundance: "If the range of a taxon is suspected to be relatively circumscribed, if a considerable period of time has elapsed since the last record of the taxon, threatened status may well be justified" (see also precautionary principle).

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