Maryland Eastern Tributaries

Stratum Summary

The Maryland eastern tributaries usually have some of the smallest proportion of degraded area in the Chesapeake Bay.  However, degradation was exceptionally high in 2003, with 64% of the area (342 km²) estimated to fail the Restoration Goals.  Degredation affected predominantly the lower Chester River and, to a lesser extent, the rivers emptying into Tangier Sound. The estimates for recent years are generally higher than earlier years (first chart below).  This trend is more clear if the random sites in the Chester River are post-stratified (second chart below).  The lower Chester River may be affected by hypoxia, and thus the trend shows high areal degredation in 1996 and 2003, two wet years.  High annual precipitation has been theorized to cause earlier and spatially more extreme stratification within the Bay, leading to more extreme hypoxia.  Sediment and nutrient runoff is also associated with high precipitation in eastern shore tributaries.

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to see basin details.

The sampling areas in the Eastern Shore stratum fall into three basins, referred to as the Upper Eastern Shore basin (yellow shading on map above), the Choptank River (raspberry shading), and the Lower Eastern Shore basin (green shading).  There are further details at the basin level which the Benthic Program provides to summarize benthic community condition for the basin Tributary Teams.  Tributary Teams consider basin summaries that synthesize monitoring information from several sources, including watershed, ambient water quality, habitat, and living resources components.  This information is linked to nutrient and sediment pollution sources and is intended to provide the Tributary Teams with resources to consult in setting Tributary Strategy Goals.