Chesapeake Bay Benthic Monitoring Program

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What is the Benthic Monitoring Program ?

Design.  Since 1994, the Chesapeake Bay Benthic Monitoring Program has consisted of two elements: a fixed-site monitoring sampling effort directed at identifying trends in benthic condition, and a probability-based sampling effort intended to estimate the area of the Maryland Chesapeake Bay with benthic communities meeting and failing to meet the Chesapeake Bay Program’s Benthic Community Restoration Goals (i.e. the "state of the bay").  The Design History section describes these sampling elements in detail and gives a brief history of how they evolved.


A satellite view of the Chesapeake Bay
and surrounding land areas. 
Red shades show urban land,
yellow indicates agriculture,
and green areas are forested.

Methods.  The methods sections describe the specific procedures that are employed for field data collection, laboratory analysis of samples, statistical assessment, and calculation of an index of biotic integrity that measures the health of the Bay.  Benthic samples are collected using four kinds of gear depending on the program element and habitat type.  Species-level identifications and ash-free dry weights are provided.  Nonparametric statistical techniques are used to determine trends in benthic condition at the fixed stations, and probability-based sampling is used to make inferences about areal extent of degradation. 

Accomplishments.  Over the past 15 years, the Maryland and Virginia Benthic Monitoring Programs have pioneered many important developments and techniques for understanding the Chesapeake Bay and estuarine environments in general.  After a period of initial research into ways in which benthic communities could be used to measure and monitor environmental conditions in the Bay, the Program developed a benthic index of biotic integrity (B-IBI).  The B-IBI was subsequently tested and verified and then applied to critical assessment issues, including relations between benthic community condition and water quality, sediment quality, and watershed stressors.  More recently, advanced tools based on the B-IBI have been developed, including better ways of estimating condition and diagnostic tools for classifying regions of the Bay affect by contaminants.  The Program has also developed biological criteria based on the B-IBI to assist in the impaired waters assessments required by the Clean Water Act (303d lists).  Further details and references for these accomplishments are available in the PDF document Maryland and Virginia Benthic Program Developments.


What are
Design and
Results Reports and
Other Documents


Revised: February 11, 2009.