Distribution of submerged aquatic vegetation in the Chesapeake Bay and tributaries and Chincoteague Bay, 1989 Draft report

[From the U.S. Government Printing Office, www.gpo.gov]

BS.,aft Report

Distribution of Submerged Aquatic Vegetation in

the Chesapeake Bay and Tributaries and Chincoteague Bay - 1989

Robert J. Orth and Judith F. Nowak

Virginia Institute of Marine Science
School of Marine Science
College of William and Mary
Gloucester Point, VA 23062

Funded by: Maryland Department of Natural Resources
Virginia Institute of Marine Science
U.S. Fish and Wildlife Service
U.S. Environmental Protection Agency (Grant X-003465-01-0,-1)
Allied-Signal Inc.
National Oceanographic Atmospheric Administration
(Grant No. NA88AA-D-CZ-091 and C188-90-002)

Draft Report Submitted to: U.S. Environmental Protection Agency
Chesapeake Bay Program
Annapolis, MD 21403
March, 1990

U.S. DEPARTMENT OF COMMERCE NOA A
COASTAL SERVICES CENTER
2234 SOUTH HOBSON AVENUE
CHARLESTON, SC 29405-241

QK
122.8
.078
1989

CONTENTS

* ~~Tables................................ IV

Figures............................... V
Executive Summary...........................VII

Acknowledgements ...........................XIII

* ~~1. Introduction........................... 1

2. SAV Species............................3
I ~~3. Methods..............................4
Introduction .........................4
Aerial photography ......................4
Mapping process........................9
SAV perimeter digitization and area calculation........13
Tests of precision and accuracy................16
Calculation of SAV bed mean area ...............17
Standard operating procedures.................17
Conversion of SAV Perimeter Points to Latitude & Longitude.. 18
Organizational provinces for analysis.............20
* ~~~~Ground truth and other data bases...............25

4. Results..............................29
Data presentation.......................29
I ~~~~Discussion ..........................47
Susquehanna Flats (Section 1).................49
Upper Eastern Shore (Section 2)................51
Upper Western Shore (Section 3)................53
I ~~~~Chester River (Section 4)...................53
Central Western Shore (Section 5)...............56
Eastern Bay (Section 6)....................56
I ~~~~Choptank River (Section 7) ..................59
Patuxent River (Section 8) ..................61
Middle Western Shore (Section 9) ...............61
Lower Potomac River (Section 10) ...............64
U ~~~~Upper Potomac River (Section 11) ...............66
Middle Eastern Shore (Section 12)...............68
Mid-Bay Island Complex (Section 13)..............70
I ~~~~Lower Eastern Shore (Section 14) ...............72
Reedville (Section 15) ....................74
Rappahannock River Complex (Section 16)............74
New Point Comfort Region (Section 17).............77
I ~~~~Mobjack Bay Complex (Section 18) ...............79
York River (Section 19)....................79
Lower Western Shore (Section 20) ...............82
I ~~~~James River (Section 21) ...................84
Chincoteague Bay .......................86

~~~~~~~~~~~~~~II

CONTENTS (CONTINUED) Pg

5. Literature Cited .........................88

* ~~6. Appendices............................

A. Species of submerged aquatic plants found in the
Chesapeake Bay and tributaries...............

B. Latitude and longitude coordinate points defining
the 21 major sections of the Chesapeake Bay
SAV study area and Chincoteague Bay ............

C. Topographic quadrangles showing distribution,
abundance, and ground truthing of SAV in 1989.......

D. SAV bed areas for each topographic quadrangle in 1989...

TABLES

I ~~Number Page

I Guidelines for acquisition of aerial photographs .....7

2 List of topographic quadrangles in Chesapeake Bay and
Chincoteague Bay SAV study areas and corresponding
* ~~~~~code numbers .......................11

3 Area description for 21 major sections in the Chesapeake
Bay SAV study area ....................23
I ~~~4 Total area of SAV by quadrangles for 1989..........30

5 Number of hectares of SAV for each of the major sections
I ~~~~~in the bay for 1989....................37
6 Number of square meters of SAV in each quadrangle of the
21 major sections for 1989 ................38

~~~~~~~~~~~~~IV

FIGURES

Number Page

1 Map of Chesapeake Bay and tributaries with locations of
all SAV beds in 1989 .................................... VIII

2 Total hectares SAV for the upper, middle, and lower zones
of the Chesapeake Bay in 1989 ...............................IX

3 Total hectares SAV in 1989 by section ...........................X

4 Approximate location of flight lines where SAV photo-
graphy was acquired in 1989 .............................6

5 Location of topographic quadrangles in the Chesapeake Bay
and tributaries and Chincoteague Bay for determining
distribution of SAV ..................................... 10

6 Crown density scale used for determining density of SAV beds:
very sparse (1), 0-10%; sparse (2), 10-40%; moderate (3),
40-70%; dense (4), 70-100% ............................... 14

7 Location of upper, middle and lower zones of the Chesapeake
Bay and the 21 major sections used for delineation of SAV
distribution patterns (see Table 3 and text and Appendix B
for exact boundaries) ........................................22

8 Distribution of SAV in Susquehanna Flats section ............ 50

9 Distribution of SAV in Upper Eastern Shore section .......... 52

10 Distribution of SAV in Upper Western Shore section .......... 54

11 Distribution of SAV in Chester River section ................ 55

12 Distribution of SAV in Central Western Shore section ........ 57

13 Distribution of SAV in Eastern Bay section .................. 58

14 Distribution of SAV in Choptank River section ............... 60

15 Distribution of SAV in Patuxent River section ............... 62

16 Distribution of SAV in Middle Western Shore section ......... 63

17 Distribution of SAV in Lower Potomac River section .......... 65

18 Distribution of SAV in Upper Potomac River section .......... 67

FIGURES (continued)

I ~~~Number Page

3 ~~~19 Distribution of SAV in Middle Eastern Shore section......69

20 Distribution of SAV? in Mid-Bay Island Complex section.....71

I ~~~21 Distribution of SAV? in Lower Eastern Shore section ......73

22 Distribution of SAV in Reedville section ...........75

1 ~~~23 Distribution of SAV in Rappahannock River Complex section ..76

24 Distribution of SAV? in New Point Comfort section .......78

25 Distribution of SAV? in Mobjack Bay Complex section ......80

26 Distribution of SAV? in York River section...........81

27 Distribution of SAV? in Lower Western Shore section ......83

28 Distribution of SAN? in James River section ..........85

29 Distribution of SAN? in Chincoteague Bay............87

~~~~~~~~~~~~~~I

EXECUTIVE SUMMARY

The distribution of submerged aquatic vegetation during 1989 in the

Chesapeake Bay, its tributaries, and Chincoteague Bay, was mapped at a scale

of 1:24,000 using black and white aerial photography. SAV bed perimeter

information was digitized and stored in a computerized data base. Ground

truth information was obtained from the U.S. Geological Survey, the U. S.

Fish and Wildlife Service, the University of Maryland Horn Point Laboratory,

Harford Community College and the College of William and Mary's Virginia

Institute of Marine Science/School of Marine Science. Citizen support via

the U. S. Fish and Wildlife Service and Chesapeake Bay Foundation, as well

as the Maryland Charterboat Association via the Maryland DNR Watermen's

Assistance Program, provided additional ground truth information.

In 1989, the Chesapeake Bay had 24.412 hectares of SAV, compared to

20,119 hectares in 1987, with 2,457 (10%), 11,544 (47%) and 10,411 (43%)

hectares occurring in the Upper, Middle and Lower Bay zones, respectively

(Figs. 1 and 2). Seventy-two percent of the SAV is concentrated in the bay

from Barren Island-Honga River to the bay mouth, exclusive of the Potomac

River (Fig. 3). Forty-nine percent (11,949 hectares) of the SAV was present

along the eastern shore (sections 12, 13, and 14) from the Barren Island-

Honga River area to just below Cape Charles (Fig. 3)

In the Upper Bay zone 79% of the SAV was located in the Susquehanna

Flats section (1945 hectares). Nine species of SAV were documented by

ground truth surveys in this section, with Mvrioohvllum spicatum being the

dominant species. Hydrilla verticillata was found in the Flats but occurred

in small isolated beds. In addition to the reduced overall abundance of SAV

from 1987, beds were generally much less dense, with 95% of all SAV beds

VII

I 3940 I5 IUSQUEHANNA R
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Figure 1. Map of Chesapeake Bay and tributaries with
locations of all SAV beds in 1989.

VIII

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Figue 2.Hecare fSV i ach r eg~Qin oftheCeaeke Bay

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Figure 3. Hectares of SAV in 1989 by section

I~~~~~~~~~~~~~

classified as very sparse, and no beds classified as dense (70-100%

coverage). In the Upper Eastern Shore section (307 hectares), SAV was

located principally in the Elk and lower Sassafras Rivers, Swan, Stillpond,

and Churn Creeks, with many of the same species as reported in the

Susquehanna Flats section. In the Upper Western Shore section (38

hectares), SAV was concentrated in Saltpeter and Seneca Creeks, with M.

snicatum and Vallisneria americana being most abundant. In the Chester

River section (167 hectares), SAV was most abundant adjacent to Eastern Neck

and Eastern Neck Island and in the lower Chester River. In this region

Ruppia maritima was the most abundant of six species which were reported.

In the Middle Bay Zone, 45% (5,196 hectares) of the SAV was found in

the Mid-bay Island Complex, where Ruppia maritima and Zostera marina were

present, in particular, the broad shoal area between Smith and Tangier

Islands. Eighteen percent (2,035 hectares) of the SAV was present in the

Middle Eastern Shore section, primarily in the Barren Island-Honga River

area, the Big and Little Annemessex Rivers, and the lower section of the

Manokin River, with R. maritima being the dominant species reported for this

area. Little or no SAV was mapped or reported from the Central Western

Shore, Middle Western Shore, and Patuxent River sections.

The Middle Bay zone also includes the entire Potomac River, where 2,614

hectares of SAV were present in 1989. SAV was concentrated in two distinct

zones: 1. the tidal freshwater region (the Upper Potomac River section with

1998 hectares) where H. verticillata remained the numerically dominant

species (eight other species were recorded from the USGS and citizen

surveys); and 2. the region around the Rt. 301 bridge (the upper portion of

the Lower Potomac River section with 616 hectares), including the Nanjemoy

and Port Tobacco Creeks, with V. americana and M. spicatum being reported

the most frequently reported species in this area. Although the total

abundance of SAV in the upper section increased from 1987 (1,665 hectares),

many of the very dense beds from the Woodrow Wilson bridge to just below

Piscataway Creek declined. The decline was offset by the large increases in

SAV from Quantico Creek to Aquia Creek, along both shores.

SAV was abundant throughout the entire Lower Bay zone except for the

James River. Forty-five percent of SAV in the Lower Bay zone was found in

the Lower Eastern Shore section, around the Fox Islands and the mouths of

major creeks (i.e Cherrystone Inlet, Hungars Creek, Mattawoman Creek,

Occahannock Creek, Craddock Creek, Pungoteague Creek and Onancock Creek).

Along the western shore, SAV was abundant in'Mobjack Bay (15% of SAV in the

Lower Bay zone), lower York River, Back River and Drum Island Flats area

adjacent to Plum Tree Island. Both R. maritima and Z. marina were abundant

throughout this zone. R. maritima continued to increase in abundance in

both the Piankatank and Rappahannock Rivers. Z. marina is present in

several sections resulting from previously successful transplant efforts.

SAV in Chincoteague Bay was little changed in distribution from 1987,

with 2,310 hectares reported in 1989. All of the SAV consisted of R.

maritima and Z. marina and was located along the eastern side of the bay

behind Assateague Island.

ACKNOWLEDGEMENTS

We would like to gratefully acknowledge all federal and state agencies

who financially supported this project: the Maryland Department of Natural

Resources (Md.DNR); the Virginia Institute of Marine Science (VIMS); the

U.S. Fish and Wildlife Service (F&WS); the U.S. Environmental Protection

Agency (USEPA); and the National Oceanographic and Atmospheric

Administration (NOAA). Also, we thank Allied - Signal, Inc. for providing

supplemental funding for this work.

Acknowledgement would not be complete without commendation for the

groups which provided ground truthing of SAV beds which was used in

conjunction with interpretation of the 1989 photography. USF&WS conducted a

survey and, with the Chesapeake Bay Foundation (CBF), also organized

citizens to report locations and species composition of grassbeds around the

bay. In addition, members of the Maryland Charterboat Association were

funded by the Md.DNR to participate in the ground truthing program and

contributed valuable information on location and species composition of SAV

beds in Maryland waters. J. Court Stevenson, Bill Dennison, and Lori Staver

of the University of Maryland, Horn Point Environmental Laboratory (HPEL),

and Stan Kollar of Harford Community College (HCC) provided ground truth-

information for certain specific regions of the Maryland portion of the Bay.

XII

Nancy Rybicki, R.T. Anderson and Virginia Carter of the U.S. Geological

Survey (USGS) provided ground truth information from the Potomac River. Ken

Moore, Sheryl Robertson, Sharon Dewing, Gene Silberhorn, Curtis Harper and

Betty Berry (VIMS) provided ground truth information for the lower bay.

The production of this report required the dedication of numerous

scientists, technicians, artists, photographers, and others. The following

people deserve a note of thanks: Linda Hurley and Kathyrn Reshetiloff,

US.F&WS; David Bleil, Md.DNR; Rich Batiuk and Rickie Price, USEPA-Chesapeake

Bay Program (CBP); Margaret Podlich (CBF). We are especially grateful to

the dedicated VIMS personnel who contributed greatly to the production of

this report: Jan Hodges, Jennifer Whiting, and Audrey Warner and Leah Nagey

for assistance in data collection and compilation; Pat Barthle for computer

programming and computer graphics; Harold Burrell, Kay Stubblefield, Diane

Bowers, Silvia Motley, and Billy Jenkins for graphic art work on the SAV

maps reproduced in Appendix C, and for figure preparation, photography and

printing; Ruth Hershner, Valise Jackson, and Janet Walker for word

processing; Pat Hall and David Boughan for computer services. Leigh

Medford, Photographic Services, Virginia Department of Transportation; Claud

Summers, U.S. Geological Survey (USGS), National Cartographic Information

Center (NCIC), Mid-Continent Mapping Center; and Craig Breen, Engineering

Media Inc., were helpful in the procurement of high quality topo maps and

map copies. Air Photographics, Inc., conducted the aerial photographic

missions and was responsible for the high quality photographs.

XIV

H ~~~~~~~~~~~SECTION I

INTRODUCTION

Submerged aquatic vegetation (SAV) continues to be one of the important

living resources of the Chesapeake Bay receiving considerable attention by

I ~~bay scientists and managers. The recent signing of an SAV management policy

by the governors of Virginia, Maryland, and Pennsylvania, and the mayor of

Washington, D. C., and the drafting of an SAV implementation plan, indicate

the committment of the bay community to preserving, protecting, and

enhancing these important systems.

Monitoring of this resource on an annual basis, one aspect supported by

the policy, has revealed the dramatic changes occurring with SAV and has

served to provide scientists and managers with a synoptic overview of the

current abundance on a baywide basis. SAV communities in the entire

I ~~Chesapeake Bay and tributaries have been photographed, mapped and the areas

I ~~of the beds digitized in 1978, 1984, 1985, 1986, 1987, and 1989 while

portions of the upper bay were mapped and digitized in 1979 and the lower

bay was mapped and digitized in 1980 and 1981 (Orth, et. al., 1979; Anderson

and Macomber, 1980; Orth, et. al., 1985, 1986, 1987, and 1989). Numerous

SAV ground surveys have been conducted but most have been limited to

specific sections. No one ground survey has delineated baywide SAV

I ~~patterns. Aerial photography has proved to be a useful tool in examining

SAV distribution patterns and, when combined with appropriate ground data,

has provided an accurate, synoptic picture of baywide SAV distribution. The

~~~~~~~~~~~~~~~~~I

I
I
goal of the 1989 work was to continue the annual monitoring of SAV on a
I baywide basis using aerial photographic methods with appropriate ground
truth to substantiate presence or absence of SAV in particular sections.

U
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SECTION 2

SAV SPECIES

Ten species of submerged aquatic vegetation are commonly found in the

Chesapeake Bay and its tributaries. Zostera marina (eelgrass) is dominant

in the lower reaches of the bay. MvrioDhvllum spicatum (water milfoil),

Potamogeton pectinatus (sago pondweed), Potamogeton perfoliatus (redhead

grass), Zannichellia palustris (horned pondweed), Vallisneria americana

(wild celery), Elodea canadensis (common elodea), CeratoDhvllum demersum

(coontail) and Najas RuadaluDensis (southern naiad) are less tolerant of

high salinities and are found in the middle and upper reaches of the bay

(Stevenson and Confer, 1978; Orth et al., 1979; Orth and Moore, 1981, 1983).

Ruppia maritima (widgeongrass) is tolerant of a wide range of salinities and

is found from the bay mouth to the Susquehanna Flats. Approximately eleven

other species are only occasionally found, and when present, occur primarily

in the middle and upper reaches of the bay and the tidal rivers (Appendix

A). Hydrilla verticillata (hydrilla), presently dominates SAV beds in the

tidal freshwater reaches of the Potomac River, although it has declined in

abundance since 1987. It has also been reported again in 1989 in the

Susquehanna Flats where its growth has not been as widespread as in the

Potomac River (Kollar, pers. comm.).

SECTION 3

METHODS

Introduction

Black and white aerial photography at a scale of 1:24,000 was the

principal source of information used to assess the distribution and

abundance of SAV in the Chesapeake Bay, its tributaries, and Chincoteague

Bay in 1989. SAV beds mapped from photographs onto United States Geological

Survey (USGS) 7.5 minute topographic quadrangles were then digitized,

providing a digital data base for analysis of bed area and location. Ground

truth information collected in 1989 was mapped onto the same topographic

quadrangles.

Aerial Photography

The 1989 SAV photography was obtained by Air Photographics

(Martinsburg, WV) using a Wild RC-20 camera, with a 153 mm (6 inch) focal

length Aviogon lens, and Agfa Pan 200 film. The camera was mounted in the

bottom fuselage of Air Photographics Piper Aztec, a twin engine

reconnaissance aircraft. Photography was acquired at approximately 12,000

feet altitude, yielding a 1:24,000 photographic scale.

Flight lines for photography were predetermined by Air Photographics

(and approved by the Principal Investigators) to include all areas known to

have SAV, as well as those areas which could potentially have SAV (i.e., all

areas where water depths were less than 2 m at mean low water), as well as

land features necessary as control points for accurate mapping (Fig. 4).

Flight lines were drawn on 1:250,000 scale USGS maps.

I ~~~Flight lines were prioritized by major sections and dates of flight

windows for aerial photography were specified by the Principal Investigators

by contract with Air Photographics. Acquisition of photography was timed to

occur at peak standing crop of species known to occur in the sections. In

addition, specific areas with significant coverage were given priority.

Prior documentation and approval by the funding agencies was required to

extend dates of flight windows if necessary. Actual dates of acquisition of

I ~~photography are noted on each quadrangle map in Appendix C.

* ~~~General guidelines for mission planning and execution (Table 1) address

tidal stage, plant growth, sun elevation, water and atmospheric

transparency, turbidity, wind, sensor operation, and plotting. Adherence to

these guidelines assured acquisition of photography under nearly optimal

conditions for detection of SAy, thus insuring accurate photo

interpretation.

I ~~~Quality assurance and calibration procedures are as follows. The

altimeter was calibrated by the Federal Aviation Administration annually.

I ~~Photographic settings were selected with an automatic exposure control. Sun

I ~~angle was measured with an indicator on the plane. Flight lines were

plotted on 1:250,000 scale maps to allow for overlap of photography. To

minimize image degradation due to sun glint, the camera was equipped with a

computer controlled intervalometer which established 60% line overlap and

20% sidelap. An automatic bubble level held the camera to within one degree

I ~~~~~~~~~~~~~~~~~5

I, �~a

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location of fligtJ lnsor18phtogrpy

TABLE 1. GUIDELINES FOLLOWED DURING ACQUISITION OF AERIAL PHOTOGRAPHS.

1. Tidal Stage - Photography was acquired at low tide, +/- 0-1.5 ft., as
I ~ ~~predicted by the National Ocean Survey tables.
2. Plant Growth - Imagery was acquired when growth stages ensured maximum
I ~ ~~delineation of SAV, and when phenologic stage overlap was greatest.
3. Sun Angle - Photography was acquired when surface reflection from sun
glint did not cover more 0than 30 percent of frame. Sun angle was
I ~ ~~~generally between 200 and 400 to minimize water surface glitter. At
least 60 percent line overlap and 20 percent side lap was used to
minimize image degradation due to sun glint.

4. Turbidity - Photography was acquired when clarity of water ensured
complete delineation of grass beds. This was visually determined from
the airplane to insure that SAV could be seen by the observer.

5. Wind - Photography was acquired during periods of no or low wind. Of f-
shore winds were preferred over on-shore winds when wind conditions
* ~~~could not be avoided.
6. Atmospherics - Photography was acquired during periods of no or low haze
and/or clouds below aircraft. There could be no more than scattered or
thin broken clouds, or thin overcast above aircraft, to ensure maximum
SAV to bottom contrast.

7. Sensor Operation - Photography was acquired in the vertical mode with
I ~ ~~less than 5 degrees tilt. Scale/altitude/film/focal length combination
permitted resolution and identification of one square meter area of SAV
* ~~~~(surface).

8. Plotting - Each flight line included sufficient identifiable land area
to assure accurate plotting of grass beds.

I ~~~~~~~~~~~~~~~~7

tilt. The scale/altitude/film/focal length combination was coordinated to

I ~~produce two foot resolution. Wind speed was monitored hourly from the

flight service available in the region. Under normal operating conditions,

flights were usually conducted under wind speeds less than 10 mph. (Above

this, wind generated waves stir the bottom sediments which can easily

obscure SAV beds in less than one hour.) Pilot experience determined what

acceptable level of turbidity would insure complete delineation of SAV beds.

At low tide the pilot should have been able to distinguish bottom features

I ~~such as SAV or algae. When turbid conditions prevailed photography did not

commence. Cloud cover did not exceed 5% of the area covered by the camera

frame. Determination of cloud cover was based on pilot experience. Records
of this parameter were kept in a flight notebook. Every attempt was made to

acquire photographs with no cloud cover below 12,000 feet. A thin haze

layer above 12,000 feet was generally acceptable. Experience has shown that

the optimal conditions given above generally occur two to three days

following passage of a cold front when winds have shifted from north-

northwest to south and moderated to less than 10 mph. Where possible, and

I ~~within the guidelines given for prioritizing and executing the photography,

* ~~flights were planned to coincide with these atmospheric conditions.

Exposed film was processed by Air Photographics. A contact print was

produced for each exposed frame. Each photograph was labeled with date of

acquisition as well as flight line number. Film and photographs were stored

under appropriate environmental conditions to prevent degradation of the

product.

I ~~~~~~~~~~~~~~~~8

I ~~Mapping Process

This study utilized USGS 7.5 minute topographic quadrangle maps as a

basis for mapping SAV beds from aerial photography, for digitizing the SAV

beds, and for compiling SAV bed area measurements. Figure 5 gives locations

* ~~of topographic quadrangles in the study area which includes all regions with

potential for SAV growth. Most quadrangles are sequentially numbered for

I ~~efficient access to data. The name corresponding to each quadrangle in

* ~~Figure 5 is listed in Table 2.

Photo interpretation to identify and delineate SAV beds utilized all

available information including knowledge of aquatic grass signatures on

film, distribution of SAV in 1989 from aerial photography, 1989 ground truth

information, and aerial site surveys. USGS published 7.5 minute topographic

quadrangle masters (1:24,000 scale) printed by the Mid-continent Mapping

I ~~Center of the USGS on stable transparent mylar were used as base maps.

Identical copies of these base maps were made at the same scale on stable

I ~~transparent mylar by the Virginia Department of Highways using a diazo

process. SAV from the 1989 aerial photographs was mapped onto these diazo

copies of USGS topographic quadrangles. Delineation of SAV bed boundaries

onto the topgraphic quadrangle maps was facilitated by superimposing the

photographic print with the appropriate mylar quadrangle on a light table.

SAV boundaries were then traced directly onto the mylar quadrangle with a

pencil. Where minor scale differences were evident between a photograph and

I ~~a quadrangle, or where significant shoreline erosion or accretion had

occurred since USGS publication of a map, either a best fit was obtained or

shoreline changes were noted on the quadrangle.

I ~~~~~~~~~~~~~~~~9

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TABLE 2. LIST OF USGS 7.5 MINUTE QUADRANGLES IN CHESAPEAKE BAY AND
CHINCOTEAGUE BAY SAV STUDY AREAS AND CORRESPONDING CODE
NUMBERS (SEE FIG. 5 FOR LOCATION OF QUADRANGLES. THOSE
TOPOGRAPHIC QUADRANGLES WITH SAV BEDS CAN BE FOUND IN
APPENDIX C).

1. Conowingo Dam, Md.-Pa. 46. Preston, Md.
2. Aberdeen, Md. 47. Quantico, Va.-Md.
3. Havre de Grace, Md. 48. Indian Head, Va.-Md.
4. North East, Md. 49. Benedict, Md.
5. Elkton, Md. 50. Prince Frederick, Md.
6. White Marsh, Md. 51. Hudson, Md.
7. Edgewood, Md. 52. Church Creek, Md.
8. Perryman, Md. 53. Cambridge, Md.
9. Spesutie, Md. 54. East New Market, Md.
10. Earleville, Md. 55. Widewater, Va.-Md.
11. Cecilton, Md. 56. Nanjemoy, Md.
12. Baltimore East, Md. 57. Mathias Point, Md.-Va.
13. Middle River, Md. 58. Popes Creek, Md.
14. Gunpowder Neck, Md. 59. Mechanicsville, Md.
15. Hanesville, Md. 60. Broomes Island, Md.
16. Betterton, Md. 61. Cove Point, Md.
17. Galena, Md. 62. Taylors Island, Md.
18. Curtis Bay, Md. 63. Golden Hill, Md.
19. Sparrows Point, Md. 64. Passapatanzy, Md.-Va.
20. Swan Point, Md. 65. King George, Va.-Md.
21. Rock Hall, Md. 66. Dahlgren, Va.- Md.
22. Chestertown, Md. 67. Colonial Beach North, Md.-Va.
23. Round Bay, Md. 68. Rock Point, Md.
24. Gibson Island, Md. 69. Leonardtown, Md.
25. Love Point, Md. 70. Hollywood, Md.
26. Langford Creek, Md. 71. Solomons Island, Md.
27. Centreville, Md. 72. Barren Island, Md.
28. Washington West, Md.-D.C.-Va. 73. Honga, Md.
29. Washington East, D.C.-Md. 74. Wingate, Md.
30. South River, Md. 75. Nanticoke, Md.
31. Annapolis, Md. 76. Colonial Beach South, Va.-Md.
32. Kent Island, Md. 77. Stratford Hall, Va.-Md.
33. Queenstown, Md. 78. St. Clements Island, Va.-Md.
34. Alexandria, Va.-D.C.-Md. 79. Piney Point, Md.-Va.
35. Deale, Md. 80. St. Marys City, Md.
36. Claiborne, Md. 81. Point No Point, Md.
37. St. Michaels, Md. 82. Richland Point, Md.
38. Easton, Md. 83. Bloodsworth Island, Md.
39. Fort Belvoir, Va.-Md. 84. Deal Island, Md.
40. Mt. Vernon, Md.-Va. 85. Monie, Md.
41. Lower Marlboro, Md. 86. Champlain, Va.
42. North Beach, Md. 87. Machodoc, Va.
43. Tilghman, Md. 88. Kinsale, Va.-Md.
44. Oxford, Md. 89. St. George Island, Va.-Md.
45. Trappe, Md. 90. Point Lookout, Md.

TABLE 2. (continued)

91. Kedges Straits, Md. 134. Cheriton, Va.
92. Terrapin Sand Point, Md. 135. Savedge, Va.
93. Marion, Md. 136. Claremont, Va.
94. Mount Landing, Va. 137. Surry, Va.
95. Tappahannock, Va. 138. Hog Island, Va.
96. Lottsburg, Va. 139. Yorktown, Va.
97. Heathsville, Va.-Md. 140. Poquoson West, Va.
98. Burgess, Va.-Md. 141. Poquoson East, Va.
99. Ewell, Md.-Va. 142. Elliotts Creek, Va.
100. Great Fox Island, Va.-Md. 143. Townsend, Va.
101. Crisfield, Md.-Va. 144. Bacons Castle, Va.
102. Saxis, Va.-Md. 145. Mulberry Island, Va.
103. Dunnsville, Va. 146. Newport News North, Va.
104. Morattico, Va. 147. Hampton, Va.
105. Lively, Va. 148. Benns Church, Va.
106. Reedville, Va. 149. Newport News South, Va.
107. Tangier Island, Va. 150. Norfolk North, Va.
108. Chesconessex, Va. 151. Little Creek, Va.
109. Parksley, Va. 152. Cape Henry, Va.
110. Urbanna, Va. 153. Chuckatuck, Va.
111. Irvington, Va. 154. Bowers Hill, Va.
112. Fleets Bay, Va. 155. Norfolk South, Va.
113. Nandua Creek 156. Kempsville, Va.
114. Pungoteague, Va. 157. Princess Anne, Va.
115. West Point, Va. 158. Wye Mills, Md.
116. Saluda, Va. 159. Bristol, Md.
117. Wilton, Va. 160. Fowling Creek, Md.
118. Deltaville, Va. 161. Port Tobacco, Md.
119. Jamesville, Va. 162. Charlotte Hall, Md.
120. Toano, Va. 163. Mardela Springs, Md.
121. Gressitt, Va. 164. Wetipquin, Md.
122. Ware Neck, Va. 165. Selbyville, Md.
123. Mathews, Va. 166. Assawoman Bay, Md.
124. Franktown, Va. 167. Berlin, Md
125. Westover, Va. 168. Ocean City, Md.
126. Charles City, Va. 169. Public Landing, Md.
127. Brandon, Va. 170. Tingles Island, Md.
128. Norge, Va. 171. Girdle Tree, Md.-Va.
129. Williamsburg, Va. 172. Boxiron, Md.-Va.
130. Clay Bank, Va. 173. Whittington Point, Md.-Va.
131. Achilles, Va. 174. Chincoteague West, Va.
132. New Point Comfort, Va. 175. Chincoteague East, Va.
133. Cape Charles, Va. 176. Anacostia, D.C.-Md.

In addition to delineating SAV bed boundaries, an estimate of percent

cover within each bed was made visually in comparison with an enlarged Crown

Density Scale similar to those developed for estimating of forest tree crown

cover from aerial photography (Fig. 6). Bed density was classified into one

of four categories based on a subjective comparison with the density scale.

These were: 1, very sparse (<10% coverage); 2, sparse (10 to 40%); 3,

moderate (40 to 70%); or 4, dense (70-100%). Either the entire bed or

subsections within the bed were assigned a number (1 to 4) corresponding to

the above density categories. Additionally, each distinct SAV unit (bed or

bed subsection) was assigned an identifying two letter designation unique to

its map. Subsections of beds were further identified as being part of a

contiguous bed by the addition of two letters unique to each contiguous bed.

These contiguous bed descriptions aid in the tracking of a single bed

between quad sheets as well as the analysis of those beds that had to be

separated due to variation in SAV density.

SAV Perimeter Digitization and Area Calculation

The perimeters of all SAV beds mapped from the aerial photography were

digitized in a clockwise direction using a Numonics Model 2400/2200

DigiTablet Graphics Analysis System having a resolution of .001 inches

(.00254 cm) and an accuracy of .005 inches (.0127 cm). Coordinates were

transmitted to a PRIME 9955 computer for area calculations and data

manipulation via software developed at VIMS. Each SAV bed was digitized at

least four times and the area reported as a mean of three.

25 10-40

35 o

450 Fi g

55 0 i 40-70

65F l 13

I75f

85 U,, 70-100

PERCENT ROWN COVER

Figure 6. Crown density scale used for determining density of SAV beds:
(1) Very sparse, 0-10%; (2) Sparse, 10-40%;
(3) Moderate, 40-70%; (4) Dense, 70-100%.

The perimeter of each SAV bed was defined by a polygon with a linear data

point density of 127 per chart inch (50 per cm, 5 meter ground resolution).

The total number of points defining any SAV bed is dependent on overall bed

size. The SAV bed perimeter was stored as X and Y coordinates in

centimeters from the quadrangle origin (lower left corner).

Any 'island' within a polygon (digitized SAV perimeter) was disregarded

as long as a line was drawn from the outside of the polygon to the 'island'

and the resulting polygon was digitized in a clockwise direction. The line

connecting the 'island' polygon to the larger surrounding polygon was drawn

in by the digitizer operator.

SAV bed area in square centimeters on the chart was calculated via the

following equation:

A = 1/2 (Xi* Y2 -X2* Y1) + (X2* Y3 - X3* Y2) + '.. + (Xn*Y1 i- X* Yn)

where Xn and Yn are the nth digitized perimeter points in centimeters. The

area is then converted from square centimeters on the chart to square meters

on the ground. This is done via the following conversion based on a chart

scale of 1:24000:

Ag(m2on ground) = Ac(cm2on chart) * 57600 (m2on ground / cm2on chart)

where A is the area on the ground of each SAV bed and A is the area on the

chart. The area on the ground is then stored for later use.

Tests of Precision and Accuracy

Prior to each digitization session, the Numonics instrument was checked

manually against a digitizing standard. After a map had been secured to the

digitizing tablet, the standard was secured to the map and digitized four

times. The information from digitizing the standard was transmitted to the

beginning of the SAV bed Perimeter File on the PRIME computer. This same

procedure was followed at the end of each digitizing session. When this

I ~~file was processed by the computer, the digitized area of each standard was

compared to the known area of the standard. If a variation between the

known and the mean of the observed areas exceeded 1.0% a warning was printed

advising the operator to check the digitizing system. In addition, checks

were made with respect to the absolute location of the digitizing standard

as secured to the map. A comparison was made between the location of the

standard before and after the digitizing session. If the absolute location

differed by more then 0.10 cm another warning to check the system was

printed. Any movement in absolute location can be indicative of digitizer

I ~~instrument drift or chart movement during the digitization session. These

* ~~checks assure that the final calculated bed locations are as accurate as

possible.

* ~~~Maximum accuracy was maintained by exclusively using mylar topographic

quadrangles rather than paper ones which can change scale as a function of

* ~~changes in air temperature and humidity in the digitizer room.

I ~~~~~~~~~~~~~~16

Calculation of SAV Bed Mean Area and Choice of Representative SAV Bed

Every SAV bed mean area was the result of at least four independent

digitizations of the outline of each SAV bed. The computer made an area

* ~~calculation of each replication and the 3 bed outlines or perimeters most

similar in terms of area were then used for the calculation of a mean area.

* ~~The perimeter defining the area most similar to the mean area was then

saved by the computer program as the representative perimeter for this

I ~~specific SAV bed. Representative perimeters for all 1989 SAV beds were

later converted to Latitude and Longitude and a copy of each on computer

tape was then cent to the EPA Chesapeake Bay Program. The areas used in the

mean area calculation do not by contract requirements have a range in excess

of 5% of the mean area. All bed areas having an error rate in excess of 5%

are flagged by the VIMS quality assurance quality control computer program

for additional error assesment. In fact, the VIMS error rate is normally

* ~~less than 1%.

A complete outline of the digitization procedure can be found in the

I ~~quality assurance project plan for the 1989 submerged aquatic vegetation,

distribution and abundance survey of the Chesapeake and Chincoteague Bays

(available from the EPA Chesapeake Bay Program Office).

Standard Operating Procedures for Quality Assurance/Quality Control

Standard operating procedures (SOPs) were developed to facilitate

I ~~orderly and efficient processing of the 1989 SAV maps and the SAV bed

perimeter computer files produced from them, and to comply with the need for

consistency, quality assurance and quality control. SONs developed include:

I ~~~~~~~~~~~~~17

a detailed procedure outlining 46 steps for digitization of SAV maps; a 47

I ~~step checklist for editing SAV perimeter computer files to insure

completeness and accuracy; a digitizer log in which all operations were

recorded and dated, and which was used to guide and record editing

operations; and a flow chart used to track progress of all operations

including all changes in file names. Examples of these SOPs are in the

quality assurance project plan for the 1987 submerged aquatic vegetation,

distribution and abundance survey of the Chesapeake and Chincoteague Bays.

Conversion of SAV Perimeter Points from X,Y Centimeters to Latitude and

I ~~Longitude

Before SAV perimeter information was to be exported to the EPA Bay

Program, the perimeter points had to be converted from X,Y centimeters to

the more generally applicable latitude and longitude. This is done via a

* ~~three step two dimensional linear interpolation between the four corner

points of every quadrangle. At the start of digitization of every chart,

I ~~the location of each corner point in X,Y cm and in latitude and longitude is

recorded at the head of the data file. The corners are numbered:

I = lower left corner or chart origin

*~~~~ 2= upper left corner

3 = upper right corner

*~~~~ 4= lower right corner

I ~~~These corner points are then used to convert each individual X,Y

perimeter point to latitude and longitude. If additional files are needed

I ~~~~~~~~~~~~~~18

for a given chart, a new set of corner points are digitized and stored at

the head of these files.

The steps for the conversion of from X,Y cm to lat. and long. are:

1. Transpose each X,Y perimeter point from the original, non

orthogonal (not at right angles) chart axes defined by the

original four corner points to a new set of orthogonal chart axes

and defined by a new set of four corner points.

2. Calculate centimeter to lat. and long. linear conversion factors

from the transposed chart corner points via:

XCONV = 0.125 (XCORNERPOINT(4) - XCORNERPOINT(1))

YCONV = 0.125 / (YCORNERPOINT(2) - YCORNERPOINT(1))

Where : XCONV is the X cm to lat,lon conversion factor.

YCONV is the Y cm to lat,lon conversion factor.

0.125 is a constant representing the distance in decimal

degrees latitude or longitude between each successive

chart corner point.

XCORNERPOINT(#) is the X value in centimeters of the

numbered chart corner point.

YCORNERPOINT(#) is the Y value in centimeters of the

numbered chart corner point.

3. Perform linear conversions from orthogonal X,Y cm perimeter point

to latitude and longitude via the following equations:

YLAT = YCHART(1) + (YPORTH * YCONV)

XLON = XCHART(1) - (XPORTH * XCONV)

WHERE : YLAT is the new Y point in decimal degrees latitude.

XLON is the new X point in decimal degrees longitude.

YCHART(#) is the latitude of the chart corner point.

XCHART(#) is the longitude of the chart corner point.

YPORTH is the Y perimeter point in cm from the orthogonal

chart coordinate system.

XPORTH is the X perimeter point in cm from the orthogonal

chart coordinate system.

These new Lat,Lon perimeter points are then stored in a special EPA

submission file for VIMS SAV Data. The submission file structure is fully

documented in the VIMS 1987 QA project plan.

Organizational Provinces for Analysis and Discussion

Discussion of the distribution of SAV in the Chesapeake Bay and

tributaries has been organized into three zones as established by Orth and

Moore (1982). The area between the mouth of the bay to a line stretching

from the mouth of the Potomac River at Smith Point in Virginia to

approximately 3 nautical miles south of Tangier Island then extending to the

eastern side of the bay to an area just south of the mouth of the Little

Annemessex River is referred to as the Lower Bay zone (Fig. 7).

The area between the south shore of the Little Annemessex River and the

south shore of the Potomac River to the Chesapeake Bay bridge at Kent Island

is referred to as the Middle Bay zone. The area between the Chesapeake Bay

bridge and the Susquehanna Flats is referred to as the Upper Bay zone. The

salinity within each zone roughly coincides with the major salinity zones of

estuaries: polyhaline (18-25�/oo), Lower zone; mesohaline (5-18�/oo),

Middle zone; oligohaline (0.5-5 /oo), Upper zone. Although the major rivers

and smaller tributaries of the bay have their own salinity regimes, the

distribution of SAV in each river is discussed within the zone where it

connects to the bay proper.

In addition, 21 major sections of the bay are identified for more

detailed discussion of SAV distribution (Fig. 7, Table 3). These sections,

which were first delineated for the 1984 survey (Orth, et. al, 1985) and

had been slightly modified for the 1987 survey, denote relatively distinct

parts of the bay and its tributaries that are readily identifiable from a

map. The section boundaries used for analysis and discussion of the 1989

SAV distribution and abundance data are those used for the 1987 report.

Sections 1 through 4 are located in the Upper Bay zone. Sections 5 through

13 are located in the Middle Bay zone, and sections 14 through 21 are

located in the Lower Bay zone. Appendix B gives the latitude and longitude

of the boundary points of each Chesapeake Bay section in decimal degrees.

SAV distribution in Chincoteague Bay is presented and discussed as a

separate section.

3940.0
SUSWUEHANNA R
CHESAPEAKE C. t
BAY ft

PATAPSCO~25C/� :
3910.0 - 4

33D40.- 0 LiF,."

3810.0 - 11 --

15
3740. 0- 14

_ 0
-"

3710.0 -

3640.0

Figure 7. Location of upper, middle and lower zones of the Chesapeake
Bay and the 21 major sections used for delineation of SAV
distribution patterns. (See Table 3 and Appendix B for exact
boundary positions.)

TABLE 3. AREA DESCRIPTION FOR EACH OF 21 MAJOR SECTIONS OF THE CHESAPEAKE
BAY SAV STUDY AREA.**

Section 1. Susquehanna Flats - all areas between and including Spesutie
Island and Turkey Point at the mouth of the Elk River to include
the Northeast River.

Section 2. Upper Eastern Shore - all areas in the Elk, Bohemia and
Sassafras Rivers, and SAV in areas on the eastern shore above
the Swan Point quadrangle.

Section 3. Upper Western Shore - all areas south of Spesutie Island and
north of the bay bridge to include the Bush, Gunpowder, Middle,
Patapsco and Magothy Rivers.

Section 4. Chester River - includes all of the Chester River, Eastern Neck,
areas north of the bay bridge on Kent Island and south of Swan
Point, and to include SAV on the Swan Point quadrangle.

Section 5. Central Western Shore - all areas south of the bay bridge and
north of Holland Point on Herring Bay to include the Severn,
South and West Rivers and Herring Bay.

Section 6. Eastern Bay - all areas south of the bay bridge on Kent Island
and north of Tilghman Island from Green Marsh Point to include
the Wye, East and Miles Rivers, Crab Alley Bay, Prospect Bay and
Poplar, Jefferson and Coaches Islands.

Section 7. Choptank River - all areas south of Tilghman Island from Green
Marsh Point and north of Taylor Island to include the Choptank
and Little Choptank Rivers.

Section 8. Patuxent River - all areas in the Patuxent River.

Section 9. Middle Western Shore - all areas south of Holland Point at
Herring Bay and north of Point Lookout on the Potomac River but
not the mouth of the Patuxent River.

Section 10. Lower Potomac River - all areas between the mouth of the Potomac
River to a line extending from Maryland Point on the north
shore, just above Nanjemoy Creek, to Somersett Beach on the
south shore.

Section 11. Upper Potomac River - all areas from upriver limit of the Lower
Potomac River Section to Chain Bridge at Washington D.C.

............................................................................

continued

TABLE 3.** (continued)

Section 12. Middle Eastern Shore - all areas south of Taylor Island and
I ~ ~~~~north of a line bisecting Cedar Island to include the Big and
Little Annemessex Rivers, Fishing Bay, and the Honga, Nanticoke,
Wicomico and Manokin Rivers.

Section 13. Mid-bay Island Complex - all areas in and adjacent to
Bloodsworth, South Marsh, Smith and Tangier Islands.

I ~~Section 14. Lower Eastern Shore - all areas south of a line bisecting Cedar
Island and located just above the Maryland-Virginia line to
Fisherman's Island.

Section 15. Reedville - includes the area between Windmill Point on the
Rappahannock River, and Smith Point at the mouth of the
* ~~~~~Potomac River.

Section 16. Rappahannock River Complex - includes the entire Rappahannock
River, Piankatank River and Milford Haven area.

Section 17. New Point Comfort Region - includes the area fronting the bay
from the lighthouse at New Point Comfort north to, but not
including, the bay entrance to Milford Haven.

Section 18. Mobjack Bay Complex - includes the East, North, Ware and Severn
Rivers, the north shore of the Mobjack Bay from New Pt. Comfort
lighthouse to the North River, and north of a line bisecting the
large shoal area around the Guinea Marsh area.

Section 19. York River - all areas along the north shore from Clay Bank to
the Guinea Marsh area and south of a line bisecting the large
shoal area around the Guinea Marsh area, and along the south
shore to include the north shore of Goodwin Island.

U ~~Section 20. Lower Western Shore - includes all areas south of Goodwin Island
to Broad Bay off Lynnhaven Inlet, excluding the James River.

Section 21. James River - all SAV in the James River including the
Chickahominy River.

I **- ~Sections 12, 13, 14, 18, 19, and 20 were given new boundaries for the
1987 report which also changed the delineation of the three major zones.
These new boundaries have been retained for the 1989 report. (See report
I ~ ~for these changes and see Figure 7 and Appendix B for boundary locations).

I ~~~~~~~~~~~~~24

Ground Truth and Other Data Bases

Ground truthing was accomplished by cooperative efforts of a number of

agencies and individuals. Although incomplete for most areas, ground

truthing confirmed the existence of some SAV beds mapped from 1989 aerial

photography, located a few SAV beds not visible from the photography, and

provided species data for many of these beds.

For those areas in Virginia waters where aerial photographic evidence

of SAV beds was inconclusive, photo-verification was accomplished by ground

truthing. Observations were principally made from small boats and by divers

snorkeling over areas indicated from the photographs. In several river

systems included in this survey (York, Piankatank and Rappahannock) where

VIMS researchers transplanted SAV (principally eelgrass), transplant sites

also were examined carefully by divers for any extant SAV. Citizen Field

Observation data (compiled by the F&WS) were also added to the Virginia maps

in Appendix C. In addition, a great deal of ground truth information could

be extrapolated from earlier studies (Orth et al., 1979; Orth and Moore,

1982) since SAV beds in this region contain primarily one or two species and

have not undergone drastic fluctuations since the first bay-wide survey in

1978.

In Maryland, ground truth data were obtained in 1989 by the USGS

Potomac River study, two SAV research and transplanting projects, a F&WS

survey, and the Citizen and Charterboat Captain volunteer surveys (both data

sets compiled by the F&WS). The field study in the Potomac River by the

USGS from D.C. to the 301 bridge near Morgantown, Md. used shoreline surveys

to document the distribution of SAV in the tidal Potomac River and

I ~~transition zone.

The USGS conducted shoreline surveys in the tidal freshwater portion of

the river and tributaries, specifically the majority of the reach between

D.C. and Indian Head (quads 40, 34, 28, and 48), from June to August, and,

in selected locations further south to Aquia Creek (quad 55), in October of

1989. These surveys were done by boat, using rakes to collect samples to

determine presence or absence of SAy. Plants were identified by species and

I ~~the proportion of each was estimated for vegetated areas. Each vegetated

area with species proportions was referenced on USGS 7.5 minute topo maps.

The transition zone was surveyed in August for SAV by spot-checking using
rakes as described above. Specifically, spot checking was done in the Port

Tobacco and Nanjemoy Creek quads. Data from these surveys were transferred

to the SAV distribution maps in Appendix C.

>The F&WS personnel surveyed selected locations by boat using rakes to

collect samples to determine presence or absence of SAV. Plants collected

were identified to species when possible. SAV sitings were referenced on

I ~~USGS 7.5 minute topo maps along with the sitings reported by the Citizen and

Chaterboat Captain surveys. Data from these surveys were transferred to the

SAV distribution maps in Appendix C.

>One SAV transplanting project being conducted on the Susquehanna Flats

by Stan Kollar of Harford Community College (HCC) provided data in the form

of species presence by percentage, primarily by visual estimates. Species

locations from these data were added to the SAV maps in Appendix C.

I ~~~A SAV research group at University of Maryland Horn Point Environmental

Laboratory (HPL) headed by Court Stevenson also provided ground truth data.

I ~~~~~~~~~~~~~26

Maps of their study sites on the Choptank River were annotated on the maps

for this report (Appendix C) indicating the species reported for 1989.

In addition to the scientific surveys, private citizens participated in

identifying SAV beds by checking areas in the bay for SAV. Two groups were

responsible for looking for SAV under the sponsorship of separate

organizations. The Maryland Charterboat Association participated in the

baywide effort, funded by the Maryland Department of Natural Resources (DNR)

Watermen's Assistance Program. Boat captains were provided with reduced SAV

quadrangle maps to aid in location of SAV beds and with data sheets on which

to record information on each SAV bed identified. Sampling of SAV sites was

undertaken at low tide. Samples were taken by hand, net or rake. Plants

were identified as to species onsite or placed in zip-lock plastic bags and

sent to the DNR for identification. (See maps, Appendix C, for these data.)

Private citizens volunteered to assist in the SAV ground survey under

guidance of the United States Fish and Wildlife Service (F&WS) and the

Chesapeake Bay Foundation (CBF). This program entailed identifying and

recording the location of SAV in the bay. Volunteers were recruited through

press releases, newsletters and personal letters. Volunteers, provided with

an identification guide of SAV, reduced 1987 SAV maps, and data sheets,

visited numerous sites around the bay. Each volunteer was asked to identify

the location where SAV was sighted, as well as water conditions, how many

and which kind of species, grass bed size, percentage area covered, and

location description. All information from the Charterboat Captain's survey

and Citizen's survey was submitted to Linda Hurley and Kathy Reshetiloff

(F&WS) for processing. Species locations were mapped in Appendix C.

Ground survey information was included on the SAV distribution and

abundance maps in Appendix C to show positions of the survey stations in

relation to the beds of SAV mapped from the aerial photographs. Each survey

I ~~was designated by a unique symbol to identify the different methods. In

most cases, the symbols on the SAV maps (Appendix C) have been enlarged and

offset from the actual sampling point to avoid confusion with the mapped SAV

bed. Where species information was available, it was included on the map

unless it was redundant.

I~~~~~~~~~~~~~~2

SECTION 4

* ~~~~~~~~~~~RESULTS

Data Presentation

SAV distribution data are presented by topographic quadrangle (Table

1 ~~4), by section and zone (Table 5), and by quadrangles within a section

(Table 6). Topographic quadrangle maps annotated with all SAV beds are

presented in Appendix C, while individual bed areas for each quadrangle are

* ~~given in Appendix D.

1989 SAV distribution data and species occurrences are first discussed

relative to the Upper, Middle, and Lower Bay zones, respectivley. The 21

sections of the Chesapeake Bay, and Chincoteague Bay, are then discussed

I ~~individually and the data compared to results from the 1987 study of

distribution and abundance.

* ~~~~~~~~~~~~~29

TABLE 4. TOTAL AREA OF SAV IN HECTARES BY TOPOGRAPHIC QUADRANGLES FOR 1978, 1984, 1985, 1986 AND 1987.

QUADRANGLE 1978 1984 1985 1986 1987 1989

1. Conowingo Dam, Md.-Pa. - - 0 0 - 0
2. Aberdeen, Md. - 0 6.34 5.77 4.18 0.66
3. Havre de Grace, Md. 803.67 1741.85 1605.81 1977.42 1857.89 1835.92
4. North East, Md. 5.62 13.31 29.46 6.95 5.99 105.51
5. Elkton, Md. 0.75 0 0 0 0 5.01
6. White Marsh, Md. - 0 0 0 0 0
7. Edgewood, Md. 10.48 49.81+ 6.31 +++ 0.52 0
8. Perryman, Md. - 2.01 4.64 0 2.93 0
9. Spesutie, Md. 0.84 411.38 439.96 369.54 379.65 187.86
10. Earleville, Md. 4.67 3.47 11.60 9.72 4.69 97.87
11. Cecilton, Md. - 0 0 0 0 0
12. Baltimore East, Md. - 0 0 0 0 0
13. Middle River, Md. 90.06 0 74.80 +++ 22.04 3.61
14. Gunpowder Neck, Md. 200.71 183.99+ 132.99 +++ 90.54 34.55
Li 15. Hanesville, Md. 9.31 5.48 10.10 7.70 42.35 12.66
16. Betterton, Md. 6.40 5.74 12.89 8.40 19.81 1.09
17. Galena, Md. 1.46 11.88 0.61 10.91 7.57 2.79
18. Curtis Bay, Md. 33.40 0 0 0 0 0
19. Sparrows Pt., Md. 10.52 0 5.56 0 0
20. Swan Point, Md. 29.86 18.65 10.25 3.33 1.60 5.24
21. Rock Hall, Md. 127.25 30.13 14.71 5.97 5.31 19.16
22. Chestertown, Md. 12.31 0 1.92 0 0 0
23. Round Bay, Md. 137.15 0 0 0 0 0
24. Gibson Island, Md. 139.45 7.61 16.07 4.09 0.26 0
25. Love Point, Md. 11.81 0 3.94 0 0 0
26. Langford Creek, Md. 1255.20 599.72 586.06 294.89 499.17 138.91
27. Centreville, Md. 38.75 0 0 0.52 1.45 0
28. Washington West, Md.-DC-Va. - 0++ 0 0 0 0
29. Washington East, DC-Md. - 0 0 0 0 0
30. South River, Md. 15.14 0 0 0 # 0
31. Annapolis, Md. 27.15 0 0.28 0.12 0
1 Y~~~~~~~~~

TABLE 4. (continued)

QUANDRANGLE 1978 1984 1985 1986 1987 1989

32. Kent Island, Md. 513.68 26.28 48.36 30.80 322.50 327.06
33. Queenstown, Md. 492.10 89.45 97.9 36.57 216.74 128.32
34. Alexandria, Va.-DC-Md. - 160.40 512.70 495.80 470.96 368.43
35. Deale, Md. 61.51 0 2.43 0.57 0
36. Claiborne, Md. 421.08 52.25 346.69 165.06 136.89 381.67
37. St. Michaels, Md. 366.09 11.14 223.91 64.03 231.60 172.45
38. Easton, Md. 1.19 0 14.33 0 0 0
39. Fort Belvoir, Va.-Md. - 0.91 1.73 7.16 19.35 63.48
40. Mt. Vernon, Md.-Va - 420.34 857.81 1080.23 1056.79 334.65
41. Lower Marlboro, Md. - 0 0 0 0 0
42. North Beach, Md. - 0 18.88 0 # 0
43. Tilghman, Md. 478.15 6.87 253.74 37.48 85.45 231.10
44. Oxford, Md. 562.96 23.25 329.10 51.91 5.51 95.94
45. Trappe, Md. 64.75 0 33.16 0 # 0
S 46. Preston, Md. - 0 0 0 0 0
47. Quantico, Va.-Md. 0 6.67 19.23 46.27 533.16
48. Indian Head, Va.-Md. - 0++ 0.21 7.51 17.59 184.02
49. Benedict, Md. 1.58 0 0 4.23 1.27 0
50. Prince Frederick, Md. - 0 0 0 0 0
51. Hudson, Md. 377.08 4.42 229.75 193.59 167.74 331.38
52. Church Creek, Md. 208.94 9.00 322.63 141.52 49.46 18.99
53. Cambridge, Md. 48.96 0 0 0 0
54. East New Market, Md. - 0 0.75 0 # 0
55. Widewater, Va.-Md. - 4.59 38.21 39.36 39.17 466.59
56. Nanjemoy, Md. 28.03 30.92 106.68 102.74 108.45 149.61
57. Mathias Pt., Md.-Va. 194.12 121.11 228.66 210.70 284.18 346.70
58. Popes Creek, Md. - 0 0 0 # 6.20
59. Mechanicsville. Md. 13.62 0 0 7.59 2.08 0
60. Broomes Island, Md. 4.94 4.37 24.71 4.14 20.20 0
61. Cove Pt., Md., 2.97 3.75 2.46 0.74 4.62 0.48
62. Taylors Island, Md. - 8.55 47.53 12.38 47.47 16.17

TABLE 4. (continued)

QUANDRANGLE 1978 1984 1985 1986 1987 1989

63. Golden Hill, Md. - 0.42 10.90 1.07 2.53 2.49
64. Passapatanzy. Md.-Va. - 0 0 0 0 0
65. King George, Va.-Md. 2.25 13.44 22.15 22.95 16.10 52.25
66. Dahlgren, Va.-Md. 8.32 2.67 1.97 2.41 14.29 65.33
67. Colonial Beach N. Md.-Va. 87.44 25.63 15.66 18.42 17.79 28.46
68. Rock Pt., Md. 22.85 0 0.27 0 0 0
69. Leonardtown, Md. 2.44 0 0 0 0 0
70. Hollywood, Md. - 0 0 1.33 4.97 0
71. Solomons Island, Md. 10.54 0.76 15.52 2.63 8.33 2.96
72. Barren Island, Md. - 0 264.99 177.17 269.81 394.52
73. Honga, Md. 126.94 5.05 178.58 194.48 632.04 773.50
74. Wingate, Md. 2.64 8.81 97.99 90.83 171.97 369.30
75. Nanticoke, Md. - 0 0 0 0 5.02
76. Colonial Beach S., Va.-Md. 61.95 11.26 0 0 0 0
77. Stratford Hall, Va.-Md. 5.53 2.16 0 0 0 0
iw 78. St. Clements Is., Va.-Md. 0.13 0 0 0 0 0
79. Piney Point, Md.-Va. - - 0.51 1.51 0 0
80. St. Marys City, Md. - - 19.01 16.66 10.48 0
81. Point No Point, Md. - - 16.50 0 0 0
82. Richland Pt., Md. 0.73 0.38 24.28 3.76 42.46 24.03
83. Bloodsworth Island, Md. 66.07 18.29 285.53 385.28 555.76 686.76
84. Deal Island, Md. 3.01 0 16.65 60.48 60.24 27.38
85. Monie, Md. 9.15 0 1.93 18.69 24.60 17.84
86. Champlain, Va. - - 0 - - 0
87. Machodoc, Va. - - 00 0 0
88. Kinsale. Va.-Md. - - 0 0 0 0
89. St. George Island, Va.-Md. - - 8.82 6.91 5.73 2.84
90. Point Lookout. Md. - - 5.76 0.58 0 0
91. Kedges Straits, Md. 156.09 366.42 474.91 637.99 693.37 781.29
92. Terrapin Sand Point, Md. 314.48 187.00 180.48 209.35 93.26 218.22
93. Marion. Md. 289.33 0 200.29 243.13 160.14 202.27

TABLE 4. (continued)

QUANDRANGLE 1978 1984 1985 1986 1987 1989

94. Mount Landing, Va. - -
95. Tappahannock, Va. - - -
96. Lottsburg, Va. - - - 0 - 0
97. Heathsville, Va.-Md. - - - 0 0 0
98. Burgess, Va.-Md. - - - 0 0 0
99. Ewell, Va.-Md. 1483.30 2308.58 2129.67 2324.36 2012.93 2423.93
100. Great Fox Is., Va.-Md. 540.65 807.81 1074.25 1362.12 1089.95 1381.80
101. Crisfield, Va.-Md. 7.48 113.01 79.22 180.46 123.22 202.04
102. Saxis. Va.-Md. - - - - 0 2.08
103. Dunnsville, Va. - -
104. Morattico, Va. - - 0 - 0 0
105. Lively, Va. - - 0 - 0 0
106. Reedville, Va. 230.40 108.56 51.17 71.28 87.99 157.88
107. Tangier Island, Va. 405.06 614.44 613.55 651.89 499.15 696.00
108. Chesconessex, Va. 482.54 808.61 827.28 920.15 911.70 972.11
109. Parksley, Va. 80.35 264.80 241.16 318.28 235.80 320.19
110. Urbanna, Va. - - - - 36.16 200.66
111. Irvington, Va. 5.31 9.33 8.26 7.50 97.34 245.43
112. Fleets Bay, Va. 133.23 155.45 120.91 132.88 235.67 334.59
113. Nandua Creek, Va. 184.86 345.10 350.51 375.97 378.70 406.24
114. Pungoteague, Va. 401.63 716.76 691.94 706.23 696.73 795.06
115. West Point, Va. - - - - - -
116. Saluda, Va. - - - - 0 19.08
117. Wilton, Va. 10.43 0 0 - 26.75 43.07
118. Deltaville, Va. 59.43 6.62 0.70 0.52 18.88 81.06
119. Jamesville, Va. 406.04 367.36 327.20 404.46 419.53 496.41
120. Toano, Va. - - - - -
121. Gressitt, Va. - - - - - 0
122. Ware Neck, Va. 256.00 203.15 171.91 168.59 194.32 278.08
123. Mathews, Va. 63.88 30.32 37.39 37.03 58.08 110.18
124. Franktown, Va. 504.49 395.26 419.66 441.77 392.70 435.85

TABLE 4. (continued)

QUANDRANGLE 1978 1984 1985 1986 1987 1989

125. Westover, Va. - .
126. Charles City. Va. - - - -
127. Brandon, Va. - - - ++++ 0 0
128. Norge, Va. 46.48 46.48** 46.48** 13.66** 0** 0
129. Williamsburg, Va. - --
130. Clay Bank, Va. - - - - 0 0
131. Achilles. Va. 797.92 741.50 710.16 702.91 755.41 963.57
132. New Point Comfort, Va. 1096.31 1092.71 1154.55 1155.33 1048.89 1264.93
133. Cape Charles, Va. 321.42 308.32 329.48 255.33 266.42 271.66
134. Cheriton, Va. 85.20 55.99 63.58 72.74 73.50 73.21
135. Savedge, Va. -
136. Claremont, Va. - - - -
137. Surry, Va. - . .
138. Hog Island, Va. - - - -
139. Yorktown, Va. 1.92 0.23 0.21 0.28 0.98 1.58
140. Poquoson West, Va. 210.44 216.93 237.70 235.96 290.53 412.40
141. Poquoson East, Va. 516.63 687.16 784.53 762.30 752.42 994.67
142. Elliotts Creek, Va. 44.58 14.48 8.41 19.91 9.43 15.90
143. Townsend, Va. 42.70 4.80 17.72 14.42 11.97 12.55
144. Bacons Castle, Va. - - - -
145. Mulberry Island, Va. - - - -
146. Newport News North, Va. - - - - 0 -
147. Hampton, Va. 218.25 233.15 287.10 270.40 283.99 304.05
148. Benns Church, Va. - - - -
149. Newport News South, Va. 1.87 0 0 - 0 0
150. Norfolk North, Va. - - - 0 0
151. Little Creek, Va. - 0 0 - 0 0
152. Cape Henry, Va. * 37.87 36.76 43.31 40.50 36.46
153. Chuckatuck. Va. - - -
154. Bowers Hill, Va. - - -
155. Norfolk South. Va. - - - -

m - - - m - m m- - - m

TABLE 4. (continued)

QUANDRANGLE 1978 1984 1985 1986 1987 1989

156. Kempsville, Va. - .
157. Princess Anne, Va. - - - - 0
158. Wye Mills, Md. - - 1.10 - - 0
159. Bristol, Md. - - 2.08 0 # 0
160. Fowling Creek, Md. - -0 0 - 0
161. Port Tobacco, Md. - - 0 1.10 5.64 12.09
162. Charlotte Hall, Md. - - 0 0 0 0
163. Mardela Springs, Md. - - 0 0 0
164. Wetipquin, Md. - - 0 0 0 0
165. Selbyville, Md. - - - - 0 0
166. Assawoman Bay, Md. - - - - 0
167. Berlin, Md. - - - - 7.06 4.98
168. Ocean City. Md. - - - - 8.42 3.45
169. Public Landing. Md. - - - - 0 0
170. Tingles Island, Md. - - - 852.47 1020.60 820.88
171. Girdle Tree. Md.-Va. - - - - 0 0
172. Boxiron, Md.-Va. - - - 687.95 664.94 653.90
173. Whittington Point, Md.-Va. - - - 189.94 207.90 161.77
174. Chincoteague West, Va. - - - 0 0 0
175. Chincoteague East, Va. - - 0 403.57 401.00 665.66
176. Anacostia, D.C.-Md. - - 0
TOTAL SAV - Chesapeake Bay 16,622.40 15,399.70 19,390.64 19,165.44 20,119.39 26.537.09
TOTAL SAV - Chincoteague Bay 2,133.93 2,309.91 2,310.52

TABLE 4. (continued)

NOTES: - Indicates quadrangle not photographed and assumed to have no SAV.
0 Indicates quadrangle photographed and no SAV noted.
* Area not flown in 1978 but most likely had SAV in 1978 based on data collected in subsequent
years.
** Area not photographed in 1984 or 1985. We made the assumption that the 1984 and 1985
distributions would be similar to the 1978 distribution. Area was photographed and mapped in
1986. Area was photographed in 1987 and was known to have SAV in 1987 but was not mapped
because SAV beds were too narrow and obscured by the shoreline at 1:24000 scale. In 1987
ground truthing revealed narrow beds fringing the shoreline of small tributaries of the
Chickahominy River (see map. Appendix C).
+ Information on SAV distribution taken from 1983 aerial photographs provided by Willie Burton
of Martin Marietta Corp.
++ Presence of SAV beds not detected from 1984 aerial photography. Information provided by
Virginia Carter of the USGS for the 1984 Potomac River Shoreline Survey indicated presence of
SAV.
+++ Aerial photography unavailable in 1986. therefore, SAV acreage data not collected. SAV
presence verified by ground truth surveys. See 1986 SAV report (Orth, et. al., 1987) for
discussion of Section 2, Upper Eastern Shore, and Section 3, Upper Western Shore, in Results,
and maps in APPENDIX C.
++++ Aerial photography unavailable in 1986, therefore, SAV acreage data not collected. SAV
presence verified by ground truth surveys. See 1986 SAV report (Orth, et. al., 1987) for
discussion of Section 21, James River, in Results.
# Presence of SAV beds not detected from 1987 aerial photography. Information provided by
Linda Hurley of the USF&WS indicated presence of SAV.

TABLE 5. NUMBERS OF HECTARES OF BOTTOM COVERED WITH SUBMERGED AQUATIC
VEGETATION IN 1989 FOR SECTIONS WITHIN THE THREE ZONES OF THE
CHESAPEAKE BAY AND IN CHINCOTEAGUE BAY. (Section boundaries
redefined for 1987 report. See Figure 7, Table 3 and Appendix B
for boundary locations.)

Zone Section AREA
(HECTARES)

1. Susquehanna Flats 1945
Upper 2. Upper Eastern Shore 307
3. Upper Western Shore 38
4. Chester River 167
Zone Total 2,457
....................................................
5. Central Western Shore 0
6. Eastern Bay 834
7. Choptank River 862
Middle 8. Patuxent River 3
9. Middle Western Shore 0
10. Lower Potomac River 269
11. Upper Potomac River 1998
12. Middle Eastern Shore 2035
13. Mid-Bay Island ComDlex 4415
Zone Total 10,416
....................................................
14. Lower Eastern Shore 4718
15. Reedville 738
Lower 16. Rappahannock River Complex 669
17. New Point Comfort Region 344
18. Mobjack Bay Complex 1589
19. York River 679
20. Lower Western Shore 1670
21. James River 4
Zone Total 10,411

....................................................
TOTAL SAV FOR CHESAPEAKE BAY 23,285

TOTAL SAV FOR CHINCOTEAGUE BAY 2,310

TABLE 6. NUMBER OF SQUARE METERS OF SAV IN 1989 FOR EACH QUADRANGLE
CONTAINED WITHIN THE 21 SECTIONS OF THE CHESAPEAKE BAY AND FOR
CHINCOTEAGUE BAY. MAP CODE NUMBERS FROM TABLE 2 IN PARENTHESES.

SECTION QUADRANGLE AREA

Susquehanna Flats - 1 Conowingo Dam (1) 0
Aberdeen (2) 6,603
Havre de Grace (3) 18,355,110
North East (4) 0
Elkton (5) 0
Perryman (8) 0
Spesutie (9) 1,087,980
Earleville (10) 0

19,449,600 sq.m
1,944.96 hectares
4,806.00 acres

Upper Eastern Shore - 2 North East (4) 1,055,036
Elkton (5) 50,136
Perryman (8) 0
Spesutie (9) 790,515
Earleville (10) 978,678
Cecilton (11) 0
Gunpowder Neck (14) 0
Hanesville (15) 126,610
Betterton (16) 10,860
Galena (17) 27,884
Swan Point (20) 0
Rock Hall (21) 30,621

3,070,340 sq.m
307.03 hectares
758.68 acres

Upper Western Shore - 3 White Marsh (6) 0
Edgewood (7) 0
Perryman (8) 0
Spesutie (9) 0
Baltimore East (12) 0
Middle River (13) 36,118
Gunpowder Neck (14) 345,544
Hanesville (15) 0
Curtis Bay (18) 0
Sparrows Point (19) 0
Swan Point (20) 0
Round Bay (23) 0
Gibson Island (24) 0

continued

TABLE 6. (continued)

Upper Western Shore - 3 (continued)
Love Point (25) 0

381,662 sq.m
38.17 hectares
94.31 acres

Chester River - 4 Betterton (16) 0
Galena (17) 0
Swan Point (20) 54,409
Rock Hall (21) 160,956
Chestertown (22) 0
Love Point (25) 0
Langford Creek (26) 1,389,220
Centreville (27) 0
Kent Island (32) 0
Queenstown (33) 69.034

1,671,619 sq.m
167.16 hectares
413.06 acres

Central Western Shore - 5 Curtis Bay (18) 0
Round Bay (23) 0
Gibson Island (24) 0
South River (30) 0
Annapolis (31) 0
Deale (35) 0
North Beach (42) 0

0 sq.m
0 hectares
0 acres

Eastern Bay -6 Annapolis (31) 0
Kent Island (32) 3,270,651
Queenstown (33) 1,214,291
Claiborne (36) 2,206,638
St. Mighaels (37) 1,646,711
Easton (38) 0
Tilghman (43) 0
Oxford (44) 0

8,338,291 sq.m
833.83 hectares
2,060.39 acres

continued

TABLE 6. (continued)

Choptank River - 7 Claiborne (36) 1,607,895
St. Michaels (37) 77,222
Easton (38) 0
Tilghman (43) 2,311,106
Oxford (44) 959,387
Trappe (45) 0
Preston (46) 0
Hudson (51) 3,313,613
Church Creek (52) 189,937
Cambridge (53) 0
East New Market (54) 0
Taylors Island (62) 161,654
Golden Hill (63) 0
Fowling Creek (160) 0

8,620,814 sq.m
862.08 hectares
2,130.20 acres

Patuxent River - 8 Deale (35) 0
Lower Marlboro (41) 0
North Beach (42) 0
Benedict (49) 0
Prince Frederick (50) 0
Mechanicsville (59) 0
Broomes Island (60) 0
Cove Point (61) 4,774
Hollywood (70) 0
Solomons Island (71) 29,595
Bristol (159) 0

34,369 sq.m
3.44 hectares
8.49 acres

Middle Western Shore - 9 North Beach (42) 0
Prince Frederick (50) 0
Hudson (51) 0
Broomes Island (60) 0
Cove Point (61) 0
Taylors Island (62) 0
Solomons Island (71) 0
Barren Island (72) 0
St. Marys City (80) 0
Point No Point (81) 0
Richland Point (82) 0

continued

TABLE 6. (continued)

Middle Western Shore - 9 (continued)
Point Lookout (90) 0

0 sq.m
0 hectares
0 acres

Lower Potomac River - 10 Nanjemoy (56) 1,496,092
Mathias Point (57) 0
Popes Creek (58) 61,980
Mechanicsville (59) 0
King George (65) 147,912
Dahlgren (66) 653,267
Colonial Beach
North (67) 284,566
Rock Point (68) 0
Leonardtown (69) 0
Hollywood (70) 0
Solomons Island (71) 0
Colonial Beach
South (76) 0
Stratford Hall (77) 0
St. Clements
Island (78) 0
Piney Point (79) 0
St. Marys City (80) 0
Machodoc (87) 0
Kinsale (88) 0
St. George
Island (89) 28,413
Point Lookout (90) 0
Lottsburg (96) 0
Heathsville (97) 0
Burgess (98) 0
Port Tobacco (161) 17,165
Charlotte Hall (162) 0

2,689,395 sq.m
268.94 hectares
664.55 acres

Upper Potomac River - 11 Washington West (28) 0
Washington East (29) 0
Alexandria (34) 3,684,402
Fort Belvoir (39) 634,809
Mt. Vernon (40) 3,346,106
Quantico (47) 5,331,638

continued

TABLE 6. (continued)

Upper Potomac River - 11 (continued)
Indian Head (48) 1,840,078
Widewater (55) 4,666,420
Nanjemoy (56) 0
Mathias Point (57) 0
Passapatanzy (64) 0
King George (65) 374,853
Dahlgren (66) 0
Port Tobacco (161) 103,741

19,982,044 sq.m
1,998.20 hectares
4,937.56 acres

Middle Eastern Shore - 12 Taylors Island (62) 0
Golden Hill (63) 24,915
Barren Island (72) 3,945,341
Honga (73) 7,734,319
Wingate (74) 3,693,344
Nanticoke (75) 50,162
Richland Point (82) 240,230
Bloodsworth
Island (83) 782,931
Deal Island (84) 273,837
Monie (85) 178,368
Terrapin Sand
Point (92) 118,467
Marion (93) 2,022,714
Great Fox
Island (100) 1,287,101
Crisfield (101) 474,794
Mardela Springs (163) 0
Wetipquin (164) 0

20,351,720 sq.m
2,035.17 hectares
5,028.91 acres

Mid-Bay Island Complex - 13 Richland Point (82) 0
Bloodsworth
Island (83) 6,085,111
Deal Island (84) 0
Kedges Straits (91) 0
Terrapin Sand
Point (92) 2,063,632
Ewell (99) 24,239,832
Great Fox Is. (100) 5,314,487

continued

TABLE 6. (Continued)

Mid-Bay Island Complex - 13 (continued)
Tangier Island (107) 6,441.425

44,144,480 sq.m
4,414.45 hectares
10,908.10 acres

Lower Eastern Shore - 14 Great Fox Island(100) 7,215,881
Crisfield (101) 1,436,282
Saxis (102) 20,770
Tangier Island (107) 518,920
Chesconessex (108) 9,721,160
Parksley (109) 3,201,754
Nandua Creek (113) 4,062,116
Pungoteague (114) 7,951,006
Jamesville (119) 4,964,022
Franktown (124) 4,358,882
Cape Charles (133) 2,716,648
Cheriton (134) 732,115
Elliotts Creek (142) 158,984
Townsend (143) 125.531

47,184,056 sq.m
4,718.41 hectares
11,659.18 acres

Reedville - 15 Heathsville (97) 0
Burgess (98) 0
Reedville (106) 1,578,771
Irvington (111) 2,454,316
Fleets Bay (112) 3.345.897

7,378,984 sq.m
737.90 hectares
1,823.35 acres

Rappahannock River Complex - 16 Tappahannock (95) 0
Dunnsville (103) 0
Morattico (104) 0
Lively (105) 0
Urbanna (110) 2,006,669
Irvington (111) 2,454,482
Fleets Bay (112) 1,212
Saluda (116) 190,787
Wilton (117) 430,680
Deltaville (118) 810,605
Ware Neck (122) 0

continued

TABLE 6. (continued)

Rappahannock River Complex - 16 (continued)
Mathews (123) 797,847

6,692,292 sq.m
669.23 hectares
1,653.66 acres

New Point Comfort Region - 17 Mathews (123) 0
New Point
Comfort (132) 3,440.852

3,440,852 sq.m
344.09 hectares
850.23 acres

Mobjack Bay Complex - 18 Ware Neck (122) 2,780,668
Mathews (123) 303,972
Achilles (131) 6,706,823
New Point
Comfort (132) 6,102,371

15,893,832 sq.m
1,589.38 hectares
3,927.37 acres

York River - 19 Toano (120) 0
Gressitt (121) 0
Williamsburg (129) 0
Clay Bank (130) 0
Achilles (131) 2,929,100
New Pt. Comfort (132) 3,104,722
Hog Island (138) 0
Yorktown (139) 15,826
Poquoson West (140) 740,234
Poquoson East (141) 0

6,789,882 sq.m
678.99 hectares
1,677.78 acres

Lower Western Shore - 20 Poquoson West (140) 3,382,530
Poquoson East (141) 9,946,190
Elliotts Creek (142) 0
Newport News
North (146) 0
Hampton (147) 3,002,001
Norfolk North (150) 0

continued

TABLE 6. (continued)

Lower Western Shore - 20 (continued)

Little Creek (151) 0
Cape Henry (152) 364,698
Kempsville (156) 0
Princess Anne (157) 0

16,695,418 sq.m
1,669.54 hectares
4,125.44 acres

James River - 21 Toano (120) 0
Westover (125) 0
Charles City (126) 0
Brandon (127) 0
Norge (128) 0
Williamsburg (129) 0
Savedge (135) 0
Claremont (136) 0
Surry (137) 0
Hog Island (138) 0
Yorktown (139) 0
Bacons Castle (144) 0
Mulberry Island (145) 0
Newport News
North (146) 0
Hampton (147) 38,602
Benns Church (148) 0
Newport News
South (149) 0
Norfolk North (150) 0
Little Creek (151) 0
Chuckatuck (153) 0
Bowers Hill (154) 0
Norfolk South (155) 0
Kempsville (156) 0

38,602 sq.m
3.86 hectares
9.54 acres

continued

TABLE 6. (continued)

Chincoteague Bay Berlin (167) 49,775
Ocean City (168) 34,490
Public Landing (169) 0
Tingles Island (170) 8,208,322
Girdle Tree (171) 0
Boxiron (172) 6,538,884
Whittington Point
(173) 1,617,859
Chincoteague West
(174) 0
Chinoteague East
(175) 6.655,878

23,105,204 sq.m
2,310.52 hectares
5,709.29 acres

DISCUSSION

In 1989, the Chesapeake Bay had 24.412 hectares of SAV, compared to

20,119 hectares in 1987, with 2,457 (10%), 11,544 (47%) and 10,411 (43%)

hectares occurring in the Upper, Middle and Lower Bay zones, respectively

(Figs. 1 and 2). Seventy-two percent of the SAV is concentrated in the bay

from Barren Island-Honga River to the bay mouth, exclusive of the Potomac

River (Fig. 3). Forty-nine percent (11,949 hectares) of the SAV was present

along the eastern shore (sections 12, 13, and 14) from the Barren Island-

Honga River area to just below Cape Charles (Fig. 3)

In the Upper Bay zone 79% of the SAV was located in the Susquehanna

Flats section (1945 hectares). Nine species of SAV were documented by

ground truth surveys in this section, with Mvrioohvllum spicatu being the