PARENT SESSION
Symposium 20: Defining and Applying Environmental Indicators in Coastal Ecosystems
Organized by: R Howe and G Niemi
Thursday, August 7. 1:30 PM to 5:00 PM, SITCC Chatham Ballroom B.

Historical and recent approaches to the assessment of ecological condition.

Howe, Robert^*,1, Karr, James², Wolf, Amy¹, ¹ University of Wisconsin-Green Bay, Green Bay, WI² University of Washington, Seattle, WA

ABSTRACT- The search for effective ecological indicators must first identify what we are trying to indicate, in other words the conceptual endpoints of field measurements. Diverse approaches to indicator development reflect the complexity of human needs and values. Whether the emphasis is on human health or ecosystem health, however, effective ecological indicators must emphasize biological condition. Analyses of physical stressors alone do not adequately address ecological integrity, the implicit endpoint of most environmental laws and regulations. In some cases, simple variables such as species richness or indicator species abundances may be useful for environmental assessment, but these approaches are likely to overlook important characteristics of local or regional ecosystems. More ambitious strategies evaluate ecological integrity or ecological health as products of multiple physical and biological variables. In this paper we review the science of ecological indicators and identify the strengths and weaknesses of different approaches to indicator development. We conclude by examining the management and policy consequences of using (or ignoring) scientifically rigorous ecological indicators.

Key words: ecological integrity, stressor, indicator, assessment