Wildlife disease in the Colorado Delta as an indicator of ecosystem health
Ecosystem health and management are relatively new paradigms for environmental management (Costanza et al., 1992) and will be continually redefined and reevaluated relative to their purpose and utility in serving human society (Costanza et al., 1992; Sutter, 1993; Grumbine, 1994; Lackey, 1998, 1999). The stimulus for ecosystem management is often associated with sustaining or restoring ecosystem health to provide values sought by humans (Costanza et al., 1992). We accept the concepts of ecosystem health and management as useful precepts. However, we argue that the orientation in serving human values often has resulted in inadequate attention being given to nonhuman species. The need to address ecosystem health for the benefit of all species that share Planet Earth is noted by Merchant (1997). This humanistic viewpoint also has economic benefits that are part of the wealth that we will pass on to future generations (Pulliam, 1995). Despite the viewpoints just noted, disease occurrence in wildlife receives inadequate consideration with regard to perspectives of ecosystem health and as a focus for ecosystem management. Evidence for this view is the limited resources allocated for wildlife disease programs and prevention efforts, and persistent attitudes within the wildlife conservation community that disease is a “natural event,” not influenced by environmental conditions or anthropogenic insults.