Marine/Tidal Bioindicators
As with freshwater systems, biological life in marine and estuarine waters can indicate the quality of a waterbody. Benthic macroinvertebrates (e.g., polychaetes) are good indicators of water quality in marine environments as their response to pollutants is comparable to those in freshwater systems. Polychaetes (commonly known as worms) are one of the most tolerant marine organisms to stressors (e.g., low oxygen, organic contamination of sediment, and sewage pollution) so they are typically used as biological indicators. In addition, macroinvertebrates also have limited mobility and a long enough life span to both avoid pollutants and accurately assess environmental stressors. Typically it is much harder to assess marine/estuarine conditions as it is often difficult to evaluate reference conditions in these ecosystems.
![Photo of Zostera](https://webarchive.library.unt.edu/eot2008/20090510053926im_/http://www.epa.gov/bioindicators/images/zostera.jpg)
Typical marine/estuarine indicators include:
- Phytoplankton indicators of water quality, specifically nutrients (e.g., nitrogen and phosphorus)
- Zooplankton sensitive to changes in water quality (e.g., toxic pollution, excess nutrients, and low oxygen) and are useful for future fisheries health assessment as they serve as a food source for animals higher up in the food chain
- Benthos also susceptible to stresses associated with toxic pollution, excess nutrients, and low oxygen
- Submerged Aquatic Vegetation serve as good indicators of water conditions
- Fish
Various programs have developed their own type of tidal/marine bioindicators. Maryland Department of the Environment developed tidal ecosystem health indicators through the MDE's Environmental Risk Assessment Program. These indicators included Submerged Aquatic Vegetation (SAV) Habitat Quality, SAV Acres, Benthic Communities of the Chesapeake Bay, Fish Index of Biotic Integrity - Chesapeake Bay, Striped Bass Juvenile Index, American Shad Population, Blue Crab Population, and Seed Oyster Production. These indicators assist to focus the overall management objectives of such resources and also help to protect and restore the habitats and populations.
The Chesapeake Bay website also details how biological resources are used as indicators of restoration success in given areas. For example, juvenile fish, crabs, diving ducks, and herons are used as indicators of restoration success in shallow water habitats such as bay grasses and wetlands, as all are susceptible to excess nutrients and turbidity. In tidal areas (e.g., aquatic reefs) adult fish, shellfish beds/reefs, and waterfowl are used as indicators of restoration success as they are susceptible to excess nutrients, turbidity, and sedimentation.
For more information on tidal/marine bioindicator and bioassessment programs please visit the following sites:
Benthic Macroinvertebrates
- USEPA Region 3 Quality Assurance Guidelines for Sorting and Identifying Marine Benthos (contact Dr. Dave Russell for more information) (PDF files - 98 K each)
- Marine/estuarine
polychaete worms and more
- with links to "Faunal Lists" and "People" (including benthic invertebrate taxonomists to help with resources for particular fauna). Lots of information on marine/estuarine polychaete worms and more at this site.
- North East Atlantic
Taxa
Fish ![Exit EPA Disclaimer](https://webarchive.library.unt.edu/eot2008/20090510053926im_/http://www.epa.gov/epafiles/images/epafiles_misc_exitepadisc.gif)
- Index of Biotic Integrity for Tidal Fish in Chesapeake Bay
- National Oceanic and Atmospheric Administration Fascinating Facts about Fish
Environmental Indicators (Specifically Biological Indicators) ![Exit EPA Disclaimer](https://webarchive.library.unt.edu/eot2008/20090510053926im_/http://www.epa.gov/epafiles/images/epafiles_misc_exitepadisc.gif)
- A Draft Status Report: Marylands Environmental Indicators(Winter 1999)
- Environmental Indicators: Measuring Our Progress slide presentation
- An example of how benthic community and habitat condition results are presented from Chesapeake Bay area is available at Bay Trends and Indicators: Benthic Community and Habitat Condition
- Animals and Plants fact sheets - includes links and general information
- The Chesapeake Bay Habitat Preservation and Restoration site provides selected indicators of restoration success
- Development of Biological Criteria for Coral Reef Ecosystem Assessment (EPA's Office of Water)
- National Coastal Condition Report (EPA's Office of Water)
- Coastal Indicators from the Heinz Center - State of the Nation's Ecosystems
Additional Information on Marine Bioindicators
- Extent and Condition of US Coral Reefs (NOAA - State of the Coastal Environment)
- Animals and Plants in Chesapeake Bay (Chesapeake Bay Program)
- Phytoplankton (Maryland DNR)
- Marine Life by the Missouri Botanical Garden