Figure 2.20. Percentage of known species
threatened in North America, 1990s.
- IUCN (1993); WCMC (1992, 1994, 1995).
- The number of threatened
species listed for all countries includes full species that are classified
by the World Conservation Union (IUCN) as endangered, vulnerable,
rare, and indeterminate, but excludes introduced species, species
whose status is insufficiently known, or those known to be extinct.