Wildlife Contaminants

Contact: Dennis Bush 517-284-5522

EGLE's report entitled "A Strategic Environmental Quality Monitoring Program for Michigan's Surface Waters" (Strategy) describes the monitoring activities that are necessary for a comprehensive assessment of water quality in Michigan's surface waters.  One component of the Strategy is wildlife contaminant monitoring.

The monitoring of productivity and contaminant levels in fish-eating (piscivorous) wildlife provides valuable information on the health of the Great Lakes ecosystem.  For instance, many persistent contaminants occur at biologically relevant concentrations in the environment, but are not easily measured in water.  It is therefore easier to measure the concentration of some contaminants in wildlife tissues than in water.  In addition, wildlife can serve as a "first alert" for the detection of changes in environmental quality and the potential for adverse effects to occur on human health.  The monitoring of contaminant levels in wildlife also provides useful information on the changes in contaminant concentrations over time.  This information helps EGLE determine whether programs have resulted in environmental improvements.  Wildlife monitoring also helps EGLE locate "hotspots" of contamination and assess whether wildlife is being adversely impacted.
The following are the objectives of the wildlife contaminant element of the monitoring program:

  1. Determine contaminant levels in piscivorous wildlife.
  2. Assist in the identification of waters that may exceed standards and target additional monitoring activities.
  3. Evaluate the overall effectiveness of EGLE programs in protecting wildlife from toxic contaminants.
  4. Determine whether new chemicals are accumulating in wildlife.

The wildlife contaminant monitoring element currently consists of two components that provide the data necessary to achieve these objectives.  These include:

  • Bald eagle nestling plasma/feathers
  • Herring gull eggs

The bald eagle and herring gull projects were started in 1999 and 2002, respectively.  Bald eagle and herring gull samples are analyzed for bioaccumulative contaminants of concern such as mercury, PCBs, and chlorinated pesticides (e.g. DDT/DDE/DDD).  Herring gull eggs are also analyzed for dioxins and furans.  The projects are assessed periodically to determine whether samples should be analyzed for additional contaminants of concern.

All bald eagle contaminant data are contained in a database maintained by the University of Maryland.  Annual reports are available from 1999 to 2008.  Periodic reports are also published for the herring gull project.

Related Links 

Bald Eagles

Temporal Trends

​​Annual Reports

Herring Gulls

​Contaminant Impacts to Wildlife