Distribution of Submerged Aquatic Vegetation in the Chesapeake Bay and Tributaries and Chincoteague Bay QH 541.5 Virginia Institute of Marine Science .~8 School of Marine Science 11.:. E-,.:-nr-c-tll Prntecfion figency 083 College of William and Mary F:<;Y~ r r fntrrnai\on Rts$urce 1987 <;-::r I 2~~521 $1; CLn~'lu'SfrCcf 1987 Phli~I~Ip~bi,'1 13107 Distribution of Submerged Aquatic Vegetation in the Chesapeake Bay and Tributaries and Chincoteague Bay - 1987 Robert J. Orth, Adam A. Fri sch, Judith F. Nowak, and Kenneth A. Moore Virginia Institute of Marine Science School of Marine Science College of Will iam and Mary Gloucester Point, VA 23062 Contributions by: Nancy Rybicki U.S. Environmental Protection Agenq R.T. Anderson Region 111 Information Resource Virginia Carter Center (3PM52) U. S . Geol ogi cal Survey 841 Che~inutStreet Reston, VA 22092 Philadelphia, PA 19107 Funded by: Mary1 and Department of Natural Resources Virginia Institute of Marine Science U.S. Fish and Wildlife Service U.S. Environmental Protection Agency All ied-Signal Inc. National Oceanographic Atmospheric Administration Final Report Submitted to: U.S. Environmental Protection Agency Chesapeake Bay Program Annapolis, MD 21403 April, 1989 Cover Photo: Aerial photograph of the Potomac River south of Washington D.C., shot at 12,000 feet by AEROECO Inc., Edgewater, MD. CONTENTS Paqe Tables .............................................................. iv Figures ............................................................. Executive Summary ................................................... Acknowledgements .................................................... 1. Introduction .................................................... 2 . SAV Species ..................................................... 3 . Methods ......................................................... Introduction ................................................ Aerial photography .......................................... Mapping process ............................................. SAV perimeter digitization and area calculation ............. Tests of precision and accuracy ............................. Calculation of SAV bed mean area ............................ Standard operating procedures ............................... Conversion of SAV Perimeter Points to Latitude & Longitude .. Organizational provinces for analysis ....................... Ground truth and other data bases ........................... Data presentation .......................................... 4 . Results ......................................................... Susquehanna Flats (Section 1) ............................... Upper Eastern Shore (Section 2) ............................. Upper Western Shore (Section 3) ............................. Chester River (Section 4) ................................... Central Western Shore (Section 5) ........................... Eastern Bay (Section 6) ..................................... Choptank River (Section 7) .................................. Patuxent River (Section 8) .................................. Middle Western Shore (Section 9) ............................ Lower Potomac River (Section 10) ............................ Upper Potomac River (Section 11) ............................ Middle Eastern Shore (Section 12) ........................... Mid-Bay Island Complex (Section 13) ......................... Lower Eastern Shore (Section 14) ............................ Reedville (Section 15) ...................................... Rappahannock River Complex (Section 16) ..................... New Point Comfort Region (Section 17) ....................... Mobjack Bay Complex (Section 18) ............................ York River (Section 19) ..................................... Lower Western Shore (Section 20) ............................ James River (Section 21) .................................... Chincoteague Bay ............................................ CONTENTS (CONTINUED) 5 . Historical Trends ................................................ 88 York River ............#..................................... 90 Rappahannock River .......................................... 95 Eastern Shore ............................................... 100 6 . Literature Cited................................................. 105 7 . Appendices ...................................................... 108 A . Species of submerged aquatic plants found in the Chesapeake Bay and tributaries ............................ 109 B. Latitude and longitutle coordinate points defining the 21 major sections of the Chesapeake Bay SAV study area and Chincoteague Bay ....................... 110 C . Topographic quadrangles showing distribution. abundance. and ground truthing of SAV in 1987 ............ 114 D. SAV bed areas for each topographic quadrangle in 1987 ..... 219 TABLES Number Paqe 1 Guide1 ines 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 Area description for 21 major sections in the Chesapeake Bay SAV study area...................................... 23 Total area of SAV by quadrangles for 1987 ................. 3 1 Number of hectares of SAV for each of the major sections in the bay for 1987 ..................................... 3 8 Number of square meters of SAV in each quadrangle of the 21 major sections for 1987 .............................. 39 FIGURES Number Paqe 1. Map of Chesapeake Bay and tributaries with locations of all SAV beds in 1987 .................................... VIII 2 Approximate location of flight lines where SAV photo- graphy was acquired in 1987 ............................. 6 3 Location of topographic quadrangles in the Chesapeake Bay and tributaries and Chincoteague Bay for determining distribution of SAV ..................................... 10 4 Crown density scale used for determining density of SAV beds: very sparse (I), 0-10%; sparse (2), 10-40%; moderate (3), 40-70%; dense (4), 70-100%. , . , . 14 5 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 6 Location of USGS vegetation sampling transects in the tidal Potomac River above Mattawoman Creek ...................27 7 Location of USGS vegetation sampling transects from Mattawoman Creek to Port Tobacco River ................... 2 8 8 Distribution of SAV in Susquehanna Flats section ............ 49 9 Distribution of SAV in Upper Eastern Shore section .......... 51 10 Distribution of SAV in Upper Western Shore section .......... 53 11 Distribution of SAV in Chester River section ................ 55 12 Distribution of SAV in Central Western Shore section... ..... 56 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 19 Percent cover of Hvdrilla in vegetated areas in the tidal Potomac River in 1987 .................................... 68 Fl GURES (continued) Number Paqe 20 Percent cover of submersed aquatic vegetation in the tidal Potomac River in 1987 ..................................... Distribution of SAV in Middle Eastern Shore section ......... Distribution of SAV in Mid-Bay Island Complex section ....... Distribution of SAV in Lower Eastern Shore section .......... Distribution of SAV in Reedville section .................... Distribution of SAV in Rappahannock River Complex section ... Distribution of SAV in New Point Comfort section ............ Distribution of SAV in Mobjack Bay Complex section .......... Distribution of SAV in York River section ................... Distribution of SAV in Lower Western Shore section .......... Distribution of SAV in James River section .................. Distribution of SAV in Chincoteague Bay ..................... Location of 3 areas used in historical trends analysis ...... SAV changes in the Ycrk River, 1971-1987 .................... SAV in the York Riverb. 1971................................. SAV in the York Riverb. 1978 ................................. SAV in the York River. 1987 ................................. SAV changes in the Ra.ppahannock River. 1971.1987 ............ SAV in the Rappahannc~ck River. 1971 ......................... SAV in the Rappahannc~ck River. 1974 ......................... SAV in the Rappahannc'ck River. 1987 ......................... SAV changes along the lower Eastern Shore. 1978.1987 ........ SAV along the lower Eastern Shore. 1978 ..................... SAV along the lower Eastern Shore. 1980 ..................... SAV along the lower Eastern Shore. 1987 ..................... v I EXECUTIVE SUMMARY The distribution of submerged aquatic vegetation during 1987 in the Chesapeake Bay, its tributaries, and Chincoteague Bay, was mapped at a scale of 1:24,000 using color 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 Mary1and Department of Natural Resources, the University of Maryland Horn Point Laboratory,