The oyster bottom described and depicted in this publication does not
represent the official Natural Oyster Bars defined by statute in the Annotated
Code of Maryland. As such, the charts and depictions shown within should not
be construed as the boundaries of the current legal oyster bars. These
depictions are representations of the historic bottom as charted prior to the
present legally designated Natural Oyster Bars. For information concerning the
legal oyster bar definitions, consult the Maryland Natural Resources Police
Hydrographic Operations at DNR’s Matapeake Facility. Maryland Department of
This document presents a description and background for a newly created
digital data file of the historic oyster bars of Maryland. These oyster bars
are not the legally defined oyster bar boundaries of current Maryland law, but
rather the traditional boundaries and names of the historic oyster bottom
where generations of watermen have harvested oysters. This project has
attempted to integrate all the available data sources into a single spatial
data file. The rapid expansion of Geographical Information Systems (GIS)
technology has allowed for the generation of a spatial (mappable) data set
that can be viewed, used and updated on a personal computer. Printed output of
this digital file is contained within this publication.
Before 1983, the legally defined oyster bars of Maryland (referred to by
statute as "Natural Oyster Bars") were identified by name. These named oyster
bars were a complex lot of approximately one thousand individual oyster bars.
Their original codification came from an early 20th century survey by C.C.
Yates. The location of oyster bars was originally based on local knowledge
which was then verified and charted by the Yates survey. Oyster bar names came
from local custom. The charts of this survey were the original legal basis for
Maryland’s oyster bars. Over the years many additions, along with a few
deletions of the originally charted oyster bars, were made to legally define
The present locations and classifications of the legally defined "Natural
Oyster Bars" were formally adopted in 1983. Extensive changes to the original
charted bar boundaries were made, and coded numbers replaced names of
individual oyster bars. These new legally defined "Natural Oyster Bar"
boundaries were developed in an attempt to simplify the complex oyster bar
boundaries of the historic oyster bar locations.
Of key interest today is that the original named oyster bar boundaries
provide the best evidence of the location of the historic oyster bottom of
Maryland. Examination of today’s oyster harvest clearly hows that much of what
was classified as productive oyster bottom at the turn of the century is no
longer capable of producing an economically viable harvest. An additional
reason for maintaining knowledge of these named oyster bar locations is the
fact that watermen still reference their harvest locations by the historic
names. Maryland Natural Resources personnel also generate monitoring data
based on the named oyster bars, because they are the best reference to true
Charting and publication of the named oyster bars are not new issues.
Natural Oyster Bar charts generated before 1983 demark the named bars. Other
investigators have published valuable charts and listings of these locations.
There is, however, great difficulty in clearly establishing a definitive
listing of all named oyster bars, because the bar names and locations have
been generated by local custom. Naming conventions and locations can be highly
variable and are a key difficulty in assembly of this type of information.
Integration of the named oyster bar file in a digital GIS format allows for
viewing and printing the oyster bars at any size or scale supported by the
original accuracy of the data. The spatial data file also includes attribute
data such as alternate names and bar size in acres. Another benefit of this
format is that the map can be used in conjunction with other data files such
as the shoreline of Chesapeake Bay or the bathymetry or bottom type of the
bay. For the purposes of this publication, charts of all of the named oyster
bars are included as an appendix. Tabular listings of the oyster bars with
supplemental information are also included within the full document, the data found in Appendix D of the Md Oyster Bars publication (of particular interest may be the center coordinates for each oyster bar). The actual data file is still available for users through the Department of Natural Resources by contacting the
Cooperative Oxford Laboratory at 410-226-0078 or by email firstname.lastname@example.org.
Click here to download the entire publication - Maryland's Historic Oyster Bottom.pdf
580 Taylor Ave., Annapolis MD 21401
Call toll-free in *Maryland* at 1-877-620-8DNR (8367)
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