Wildlife indicators

Several candidate wildlife indicators are suggested and discussed in this chapter. In addition, we recognize that valuable sources of data on residue-effect relationships are available to assist in the selection of habitat-specific indicators (Jarvinen and Ankley 1999 USCOE and USEPA 2005). Although this chapter emphasizes animals, similar considerations and literature exist for plants and microorganisms as bioindicators and biomarkers (National Research Council 1989 USEPA 1997 Gawel et al. 2001 Citterio et al. 2002 Yuska et al. 2003). 

In choosing wildlife indicators of mercury contamination, emphasis should go to 3 key considerations 1) efficacy in quantifying the probability that mercury in the environment will produce an adverse effect in exposed organisms or populations 2) the degree of harm that may be anticipated 3) and the integration of these data to characterize environmental health. 

Wildlife indicators can establish baseline conditions, act as early warning signals of environmental problems, identify the extent of contamination, define critical pathways and responses at multiple trophic levels, as well as integrate biological exposure with the physical and chemical environment (Farrington 1991). Indicator selection is based on a combination of criteria or characteristics that include (Jenkins 1981) ... 

Wildlife indicators of mercury exposure and trends are important elements of a comprehensive approach to assess mercury in the environment and the monitoring of trends that may assist regulators and the regulated community in long-term evalnation of the need and usefulness of mercury somce controls. It is important to understand, however, that bioindicator data alone are insufficient to answer snch critical qnestions as identification of mercniy sonrces, or the relative importance of local, regional, and global inputs of mercury somces to atmospheric deposition and errvirorrmerrtal loading in specific areas. 

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