Virginia Coastal Program: 2003 Coastal Grant Project Description and Final Summary
Project Task:
FY2003 Task 10
Grantee:
Virginia Institute of Marine Science
Project Title:
2003 Submerged Aquatic Vegetation Distribution and Abundance Survey of Chesapeake Bay, its Tributaries and Chincoteague Bay
Project Description as Proposed:
Submerged aquatic
vegetation (SAV) is a critical living resource in Virginia’s
coastal waters that has undergone rapid and dramatic fluctuations
in distribution and abundance over the last two decades. It is being
subjected to declines in water quality and to ever increasing pressure
from recreational, commercial, and industrial demands. Because SAV
is dependent on good water quality to which it responds over short
time scales, it can be an important indicator of water quality.
In 2003, VIMS will continue the annual SAV survey program, begun
in 1984, by mapping SAV in the shoal areas of the entire Chesapeake
Bay and its tributaries as well as Chincoteague Bay from aerial
photography acquired during late spring to late summer.
Black & white aerial photography will be acquired at a photographic
scale of approximately 1:24,000, following guidelines that address
tidal stage, plant growth, sun angle, turbidity, wind, atmospheric
transparency, sensor operation and land features to allow for acquisition
of photographs under near optimal conditions.
For Virginia waters, the first priority will be obtaining data from
the mainstem Chesapeake Bay shorelines. The second priority will
be obtaining data for the Chesapeake Bay embayments on the Eastern
Shore. The third priority will be obtaining data from the upper
tidal portions of the major western shore tributaries (James, York,
Rappahnannock).
Ground data on species distribution and abundance will be collected
by participating agencies and citizen groups from as many of the
Chesapeake Bay Program segments as possible.
The aerial photographs will be evaluated for SAV signatures using
all available information. Photographs containing SAV signatures
will be orthographically corrected and mosaiced by USGS 7.5 minute
topographic quadrangles using Orthobase and Imagine image processing
software .
The perimeters of all SAV beds mapped from the 2003 aerial photography
will be delineated on-screen using ArcInfo geographic information
system (GIS) software and stored in an ArcInfo GIS database. Preliminary
maps will be posted to the VIMS SAV web page (www.vims.edu/bio/sav)
during the digitization process.
VIMS will maintain and update, as necessary, a Quality Assurance
Project Plan detailing the quality control procedures followed to
insure proper acquisition of aerial photography and accurate mapping
and digitization of data under this scope of work.
The contribution of CZM federal funds is for partial financial support
of this multi-funded program. Completion of the other tasks required
to produce the above deliverables is dependent upon acquiring the
remainder of the funds from other state and federal sources. Funding
is expected from the Maryland's Department of Natural Resources
(from Maryland Coastal Zone Management Grant), and US EPA’s
Chesapeake Bay Program.
Federal Funding:
$59,010
Project Contact:
Bob Orth, 804.684.7392, jjorth@vims.edu
Project Status:
Grant Closed
Final Product Received:
Project Summary Provided by Grantee:
The distribution of submerged aquatic vegetation (SAV) in Chesapeake
Bay, its tributaries, and the coastal bays of the Delmarva Peninsula,
was mapped from black and white aerial photographs. These were taken
between May and November 2003, at a scale of 1:24,000, encompassing
193 flight lines. In addition, color aerial photography acquired
by St. Mary's County, Maryland and the Metro Washington Council
of Governments provided coverage for sections of the lower Potomac
River.
For 2003, 24,966 hectares (61,694 ac) of SAV were mapped in Chesapeake
Bay and its tributaries. However some portions of the Bay were not
flown due to adverse weather in the spring and summer and Hurricane
Isabel in the fall. These regions, including Tavern and Swan creeks;
lower Chester River; upper Wicomico River; Prentice, Dividing, and
Ball creeks; Dameron Marsh; and Great Wicomico River were not fully
mapped in 2003. These regions had 1,220 ha of SAV in 2002 (3,015
ac, 3% of the 2002 total).
In order to ensure a valid analysis of change in SAV distribution
and abundance given the reduced region mapped in 2003, all direct
comparisons to previous years in the report are restricted to only
those regions that were mapped in both years. Partial totals for
2002 have been computed for CBP segments, Bay zones, and the entire
Bay using only those regions mapped for both years.
Significant changes in SAV distribution were measured between 2002
and 2003. SAV decreased 30% (10,576 ha, 26,134 ac) in the regions
mapped for both years.
SAV decreased in all three zones (Upper, Middle, and Lower) geographic
zones delineated for Chesapeake Bay. In 2003, SAV increased in 12,
decreased in 42, and remained unvegetated in 24 of the 78 CBP segments
In the Upper Bay Zone (17 CBP segments extending south from the Susquehanna River to the Chester and Magothy rivers), 4,215 hectares (10,416 ac) of SAV were mapped for 2003. However, portions of the zone, including the upper central Chesapeake Bay and the lower Chester River, representing 64 ha (157 ac, 1.2% of the zone total) of SAV in 2002 were not mapped for 2003. Comparing the same mapped regions between 2002 and 2003, SAV declined from 5,264 hectares (13,009 ac) in 2002 to 4,200 hectares (10,378 ac) in 2003. In the Middle Bay Zone (34 CBP segments extending south from the Bay Bridge to the Rappahannock River and Pocomoke Sound, and including the Potomac River), 12,333 hectares (30,475 ac) of SAV were mapped for 2003. However, portions of the zone, including upper Wicomico River; Prentice, Dividing, and Ball creeks; Dameron Marsh; and Great Wicomico River representing 1,157 ha (2,858 ac, 5.4% of the zone total) of SAV in 2002 were not mapped for 2003. Comparing the same mapped regions between 2002 and 2003, SAV decreased 41% from 20,280 (50,115 ac) in 2002 to 11,869 (50,115 ac) in 2003. In the Lower Bay Zone (27 CBP segments covering the region south from the Rappahannock River and Pocomoke Sound regions to the mouth of the Bay), 8,418 hectares (20,803 ac) were mapped for 2003. SAV decreased 12% (1,100 ha, 2,718 ac) in 2003. In the Delmarva Peninsula Coastal Bays Zone (Assawoman, Isle of Wight, Sinepuxent, Chincoteague, and Southern Virginia Coastal Bays) 7,414 hectares (18,320 ac) were mapped in 2003, a 1% (94 ha, 233 ac) increase from the 2002 level of 7,319 hectares (18,087 ac). Most of the SAV mapped in the southern Virginia Seaside Bays (or Atlantic Coast Bays) segment were the result of successful restoration efforts initiated in 1997 through the Virginia Coastal Program's.
The aerial survey is critical because the 1992 amendments to Chesapeake Bay Agreement uses the distribution and abundance of SAV as documented by the baywide aerial survey as an initial measure of progress in the restoration of living resources and water quality.
The final report and GIS datasets are available on the Internet at http://www.vims.edu/bio/sav/sav03
Form C end
Disclaimer: This project summary provides the federal dollars initially awarded to the grantee. Due to underexpenditure or reprogramming of grant funds, this figure may change. For more information on the allocation of coastal grant funds, please contact Laura McKay, Virginia Coastal Program Manager, at 804.698.4323 or email: Laura.McKay@deq.virginia.gov
A more detailed Scope of Work for this project is available. Please direct your request for a copy to Virginia.Witmer@deq.virginia.gov
