Measuring changes in biodiversity conservation classification of species and how this depends on measures including changes in the geographic range and number of individuals within that range, the date the species was last recorded, and the extent of habitat.Threats to biodiversity assessment of threat in defining conservation categories for a species and/or ecosystem, including extinct in the wild, conservation dependent, critically endangered, endangered, and vulnerable.This is all I could find in the textbook that I think relates to one or both of these points:
Spoiler
Conservation categories
Classifying species according to their conservation status provides a framework for setting priorities for the allocation of the limited resources available for conservation.
We recognise three different components that contribute to the rarity of a species.
Population size
o The density or number of individuals within a local area.
May range from low to high
Geographic range
o The spatial distribution of the species.
May range from restricted to widespread
Specificity of habitat
o The variety of ecological conditions within which a species can survive.
May range from wide/general to specific/narrow
A population described as rare does not necessarily face imminent extinction. Rarity is an important factor underlying the classification of threatened species. The IUCN has developed a classification scheme that is widely used in conservation management.
IUCN: International Union for the Conservation of Nature
Extinct: There is no reasonable doubt that the last individual has died.
Extinct in the wild: The taxon is known to exist in cultivation, captivity, or as a naturalised population. Exhaustive surveys have failed to record an individual in the wild.
Critically endangered: The taxon is facing an extremely high risk of extinction in the wild in the immediate future.
Endangered: The taxon is facing a very high risk of extinction in the wild in the near future.
Vulnerable: The taxon is not endangered, but is facing a very high risk of extinction in the medium-term future.
Near threatened: The taxon is close to meeting the thresholds for threatened or would be threatened if not for an ongoing taxon-specific conservation program.
Least concern: The taxon has been evaluated to have a low risk of extinction.
Data deficient: There is inadequate information to make a direct or indirect assessment of its risk of extinction based on its distribution or population status.
Not evaluated: The taxon has not yet been assesses against the criteria.
A series of criteria has been published for determining when a species fits into the 3 threatened categories. It includes:
Population size
Geographic distribution
Number of mature individuals in the wild
Probability of future extinction in the wild
Ratings may be inconsistently applied due to guesswork when data is lacking.
Does anyone know what we need to know for each dot point? I assume that information is a mix of both dot points but I don't really know what it is exactly that we need to know.