Species considered for inclusion as Species of Greatest Conservation Need (SGCN) had to occur within the state (www.bison-m.org/) and meet at least one of the following conditions:
- Declining: Species that have experienced substantial long-term declines in habitat or numbers.
- Vulnerable: Species in which some aspect of their life history and ecology makes them disproportionately susceptible to decline within the next 10 years. Factors include, but are not limited to, concentration to small areas during migration or hibernation; low reproductive rates; susceptibility to disease, inability to respond to changing climate conditions, habitat loss, wildfire, and overexploitation for anthropogenic purposes.
- Endemic: Species that are limited to New Mexico.
- Disjunct: Species that have populations geographically isolated from other populations of the same species and are thereby disproportionately susceptible to local decline or extirpation.
- Keystone: Species that are crucial to the integrity and the functioning of their ecosystems. These species may represent more value to conservation of biological diversity than the size of their population or their distribution would suggest.