. The Canadian field-naturalist. 324 The Canadian Field-Naturalist Vol. 113. 1980 1985 1990 1995 Year Figure 1. Proportion of total at-risk designations within each of the major taxonomic groups. Data for reptiles, amphibians, invertebrates, and lichens are not included because they comprise a small proportion of total listings. to a lower category of risk, and, in 19 cases, species were uplisted to a higher category of risk. Proportion of Infra-Specific Designations COSEWIC designations include subspecies and populations as well as full, taxonomic species. Of the 307 at-risk designations, 233
. The Canadian field-naturalist. 324 The Canadian Field-Naturalist Vol. 113. 1980 1985 1990 1995 Year Figure 1. Proportion of total at-risk designations within each of the major taxonomic groups. Data for reptiles, amphibians, invertebrates, and lichens are not included because they comprise a small proportion of total listings. to a lower category of risk, and, in 19 cases, species were uplisted to a higher category of risk. Proportion of Infra-Specific Designations COSEWIC designations include subspecies and populations as well as full, taxonomic species. Of the 307 at-risk designations, 233 (76%) are taxo- nomic species (Table 4). The remaining 71 (23%) are populations or subspecies (or varieties) of taxo- nomic species that are not at risk in Canada. The percentage of infra-specific designations varies dramatically between taxonomic groups (Table 4). For example, 44% of mammal designa- tions and 1 % of plant designations are at the popula- tion level as compared to 10% for all designations. Over 53% of reptile designations are the subspecific level as compared to a cross-taxa average of 14%. A total of 91% of fish designations and 89% of plant listings are at the taxonomic species level compared to only 40% of reptile designations. These trends largely reflect the number of species in a taxonomic group and/or the scientific and popu- lar attention they receive. For example, there are few (194) mammal species in Canada and designation of the well-known, taxonomic species were largely completed early in COSEWIC s operations leaving the Mammal Subcommittee with the opportunity to place greater emphasis on populations and sub- species in later years (Figure 2). The percentage of subspecies and population designations for mammals increased from 30% in 1980 (10 mammal designa- tions) to 56% in 1998 (52 mammal designations). By contrast, work is only partially completed on the 3123 species of Canadian vascular plants (Mosquin et al. 1995: Appendix 1) necessitating that
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