Biodiversity Conservation Regulation 2017

The species has undergone or is likely to undergo within a time frame appropriate to the life cycle and habitat characteristics of the taxon—

for critically endangered species—a very large reduction in population size, or

for endangered species—a large reduction in population size, or

for vulnerable species—a moderate reduction in population size.

The determination of that criteria is to be based on any of the following—

direct observation,

an index of abundance appropriate to the taxon,

a decline in the geographic distribution or habitat quality,

the actual or potential levels of exploitation of the species,

the effects of introduced taxa, hybridisation, pathogens, pollutants, competitors or parasites.