Virginia Coastal Program: 2004 Coastal Grant Project Description and Final Summary
Project Task:
FY2004 Task 09
Grantee:
Virginia Institute of Marine Science
Project Title:
SAV Mapping in Chesapeake & Chincoteague Bays
Project Description as Proposed:
Submerged aquatic
vegetation (SAV) is a critical living resource in Chesapeake Bay
that has undergone rapid and dramatic baywide fluctuations in distribution
and abundance over the last two decades, and 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 FY 2004, 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 from aerial photography acquired during
late spring to late summer.
Black & white aerial photography will be acquired at a photographic
scale of approximate 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 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 and included in the
final report.
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 2004 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.
The results of the annual survey are important for a number of reasons:
1. Virginia Secretary of Natural Resources must report annually
on Nov. 1 of each year (effective Oct. 1, 2001) to various Virginia
House and Senate Committees the status of SAV abundance from the
annual surveys (2.2-220). This measure has specific relevance to
implementation of the blue crab fisheries management plan (28.2-203.1).
2. The annual survey has been able to detect major annual changes
either from direct impacts (clam dredging) or indirect effects (Tangier
Sound SAV losses) shortly after they occur. This information has
been used to alert resource managers so that prompt action can be
taken. The survey is “the eye in the sky.”
3. The annual survey is becoming critical to the emerging issues
of SAV restoration and its effectiveness in rehabilitating sites
with no or little SAV.
4. The aerial survey directly supports the requirements of the 1992
amendments to Chesapeake Bay Agreement. Here the distribution and
abundance of SAV, as documented by baywide aerial surveys, is used
as a measure of progress in the restoration of living resources
and water quality. Most importantly, Directive No. 93-3 signed by
the Chesapeake Executive Council commits to “agree to work
to restore SAV to their historical levels” and “agree
to an interim restoration goal of 114,000 acres baywide as documented
through the baywide aerial survey.”
5. The annual survey will be a critical tool for evaluating progress
towards the new SAV restoration goals that are being developed as
a component of the Chesapeake 2000 Agreement. Progress towards these
long-term goals can only be evaluated in the context of detailed
inter-annual changes in SAV distribution.
Federal Funding:
$59,010.00
Project Contact:
Robert J. 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 Maryland and Virginia coastal bays of the Delmarva Peninsula, was mapped from black and white aerial photographs. These were taken between May and December 2004, at a scale of 1:24,000, encompassing 173 flight lines. In addition, color aerial photography acquired by Air Survey Inc. provided coverage for sections of the upper Potomac River.
For 2004, 29,519 hectares (72,945 acres) of SAV were mapped in Chesapeake Bay and its tributaries. Notable changes in SAV distribution were measured between 2003 and 2004. SAV increased 14% from 24,888 ha (60,512 ac) in 2003 to 27,891 ha (68,922 ac) in 2004 in the regions mapped for both years.
SAV increased in two (Upper and Middle) and decreased in one (Lower) geographic zones delineated for Chesapeake Bay. In 2004, SAV increased in 39, decreased in 17, and remained unvegetated in 22 of the 78 CBP segments.
The notable changes in SAV distribution in 2004 are the result of substantial increases in freshwater species in the upper and mid-bay regions, notably the Susquehanna Flats, Elk River, and Gunpowder River. SAV declined in the higher salinity lower region of the bay. This decline is a result of Hurricane Isabel which heavily impacted some SAV beds in this region in 2003.
The full report can be viewed at: www.vims.edu/bio/sav/sav04/index.html
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
