Virginia Coastal Program: 2006 Coastal Grant Project Description and Final Summary
Project Task:
9
Grantee:
Virginia Institute of Marine Science
Project Title:
2006 Submerged Aquatic Vegetation Distribution and Abundance Survey of Virginia’s Chesapeake Bay and its Tributaries and the Seaside Bays of the Delmarva Peninsula
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 2006, 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 2006 aerial photography will be delineated on-screen using ArcInfo geographic information system (GIS) software and stored in an ArcInfo GIS database. A final report will include maps of all SAV beds, and areas of these beds. The report will be published on the VIMS web site, as in past years.
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 annual survey will be a critical tool for evaluating progress towards the new SAV restoration goals in the Chesapeake 2000 Agreement. In 2003, the CBP adopted the Strategy to Accelerate the Protection and Restoration of SAV in Chesapeake Bay including a new baywide restoration goal of 185,000 acres by 2010. Progress towards these long-term goals can only be evaluated in the context of detailed inter-annual changes in SAV distribution.
Federal Funding:
$60,000
Project Contact:
Robert J. Orth, 804.684.7392; jjorth@vims.edu
Project Status:
10/1/2006 - 12/31/2007; Project Completed
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 June and December 2006, at a scale of 1:24,000, encompassing 181 flight lines.
For 2006, 23,941 hectares (59,160 acres) of SAV were mapped in Chesapeake Bay and its tributaries.
Notable changes in SAV distribution were measured between 2005 and 2006. SAV decreased 25% from 31,671 ha (78,263 ac) in 2005 to 23,903 ha (59,068 ac) in 2006 in the regions mapped for both years.
SAV decreased in all three (Upper, Middle and Lower) geographic zones delineated for Chesapeake Bay. In 2006, SAV increased in 13, decreased in 41, and remained unvegetated in 24 of the 78 CBP segments.
In the Upper Bay Zone (17 Chesapeake Bay Program (CBP) segments extending south from the Susquehanna River to the Chester and Magothy rivers), SAV decreased 20% from 7,877 ha (19,465 ac) in 2005 to 6,286 ha (15,532 ac) in 2006. 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), 12,407 ha (30,659 ac) of SAV were mapped for 2006. Comparing the same mapped regions between 2005 and 2006, SAV decreased 23% from 16,016 ha (39,577 ac) in 2005 to 12,407 ha (30,659 ac) in 2006. 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), 5,248 ha (12,969 ac) of SAV were mapped for 2006. Comparing the same mapped regions between 2005 and 2006, SAV decreased 33% from 7,778 ha (19,221 ac) in 2005 to 5,211 ha (12,876 ac) in 2006.
In the Delmarva Peninsula Coastal Bays Zone (Assawoman, Isle of Wight, Sinepuxent, Chincoteague, and southern Virginia coastal bays), 4,524 ha (11,179 ac) of SAV were mapped for 2006. Since this region was not mapped in 2005, comparisons are with 2004, when it was last mapped. In this Zone, SAV decreased 36% from 7,033 ha (17,380 ac) in 2004 to 4,524 ha (11,179 ac) in 2006.
This report including maps and data showing SAV distribution is available at: http://www.vims.edu/bio/sav/sav06/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
