SE M3ER 985 U.s. - artm nt of h - n erior S ate of D lawa FiSh and Wildlife Service Department of Natural Resourc and Enviro mental Con ra I WETLANDS OF DELAWARE by Ralph W. Tiner, Jr. Regional Wetland Coordinator Habitat Resources U.S. Fish and Wildlife Service Region 5 Newton Corner, MA 02158 SEPTEMBER 1985 Project Officer David L. Hardin Department of Natural Resources and Environmental Control Wetlands Section State of Delaware 89 Kings Highway Dover, DE 19903 Cooperative Publication U.S. Fish and Wildlife Service Delaware Department of Natural Region 5 Resources and Environmental Habitat Resources Control One Gateway Center Division of Environmental Control Newton Corner, MA 02158 89 Kings Highway Dover, DE 19903 This report should be cited as follows: Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service, National Wetlands Inventory, Newton Corner, MA and Delaware Department of Natural Resources and Environmental Control, Wetlands Section, Dover, DE. Cooperative Publication. 77 pp. Acknowledgements Many individuals have contributed to the successful completion of the wetlands inventory in Delaware and to the preparation of this report. The Delaware Department of Natural Resources and Environmental Control, Wetlands Section contributed funds for wetland mapping and database construction and printed this report. David Hardin served as project officer for this work and offered invaluable assistance throughout the project, especially in coor­ dinating technical review of the draft report and during field investigations. The U.S. Army Corps of Engineers, Philadelphia District also provided funds for map production. William Zinni and Anthony Davis performed wetland photo interpretation and quality control of draft maps, and reviewed portions of this report. Their work serves as the foundation for this report. John Organ provided quality control of interpreted photographs. The Service's National Wetlands Inventory Group in St. Petersburg, Florida provided technical support for producing the wetland maps and for creating the Delaware wetland database. In particular, John Montanari, Ross Pywell, Robin Gebhard, and Snsan Hazellief provided major support. The following persons reviewed the draft manuscript and provided additional information: Dr. John Carey (DNREC), Inez Connor (FWS), Dr. Franklin Daiber (University of Delaware), Richard Dyer (FWS), Tony Florio (DNREC), Dick Hall (SCS), Dr. Glenn Kinser (FWS), Charles Lesser (DNREC), Dr. Blake Parker (FWS), Ron Vickers (DNREC), Dr. Bill Wilen (FWS), and Bob Zepp (FWS). The work of the individuals who typed portions of this report and its earlier draft is acknowledged: Lynne Ricci (draft manuscript), Alicia Bruneau (tables), Priscilla Arsenault (final manuscript), and Rachel Caliendo (final manuscript). Graphic 'support was provided by Debra McGeever and the enclosed figure showing the distribution of Delaware's wetlands was prepared by Kelly Drake and Fred Seavey. Cover photo credits; Martin (wood duck), Tiner (estuarine emergent wetland), Tiner (swamp milkweed) Zinni (palustrine forested wetland), Zinni (wetland with skunk cabbage), and Fitzharris (great blue heron). Table of Contents Page Acknowledgements. : ............................................................................. i List of Figures ................................................................................. iv List of Tables .................................................................................. v List of Plates .................................................................................. vi Chapter 1. Introduction........................................................................ 1 Need for a Wetlands Inventory in Delaware ..................................................... 2 Description of the Study Area . .. 2 Purpose and Organization of This Report . ... 2 References .................................................................................. 2 Chapter 2. U.S. Fish and Wildlife Service's Wetland Definitiou aud Classification System .............. 4 Introduction. .. 4 The Service's Definition of Wetland ............................................................ 4 The Service's Wetland Classification System ...........................................•......... 7 References .................................................................................. 12 Chapter 3. National Wetlauds Iuventory Mapping Techniqnes and Results ............................ 13 Introduction ................................................................................. 13 Wetlands Inventory Techniques ................................................................ 13 Wetlands Inventory Results .................................................................... 17 National Wetlands Inventory Maps ........................................................... 17 Wetland and Deepwater Habitat Acreage Summaries ........................................... 17 State Totals ............................................................................. 17 County Totals ........................................................................... 17 Summary .................................................................................... 20 References .................................................................................. 22 Chapter 4. Wetland Hydrology ................................................................. 23 Introduction ................................................................................. 23 Tidal Wetland Hydrology ..................................................................... 23 Nontidal Wetland Hydrology .................................................................. 24 References .................................................................................. 26 Chapter 5. Hydric Soils of Delaware ............................................................ 27 Introduction ................................................................................. 27 Definition of Hydric Soil. ..................................................................... 27 Major Categories of Hydric Soils ............................................................... 27 National List of Hydric Soils .................................................................. 29 Delaware Hydric Soils ........................................................................ 29 Acreage of Hydric Soils ....................................................................... 29 Description of Hydric Soils .................................................................... 30 References .................................................................................. 33 I ii Chapter 6. Vegetation and Plant Communities of Delaware's Wetlands .............................. 34 Introduction ................................................................................. 34 Hydrophyte Definition and Concept , ........................................................... 34 Wetland Plant Communities ................................................................... 34 Marine Wetlands ........................................................................... 35 Estuarine Wetlands ......................................................................... 35 Riverine Wetlands .......................................................................... 39 Palustrine Wetlands ....................................................................... .40 Lacustrine Wetlands ....................................................................... .45 Rare and Endangered Wetland Plants: ......................................................... .46 Summary ................................................................................... 47 References ................................................................................. .47 Chapter 7. Wetland Values ..................................................................... 48 Introductiou ................................................................................ .48 Fish and Wildlife Values ..................................................................... .48 Environmental Quality Values ................................................................. 50 Socio-economic Values ........................................................................ 53 Summary ................................................................................... 56 References ................................................................................... 56 Chapter 8. Delaware Wetland Trends ............................................................ 59 Introduction ................................................................................. 59 Forces Changing Wetlands .................................................................... 59 Wetland Trends .............................................................................. 60 Future Outlook .............................................................................. 63 References .................................................................................. 63 Chapter 9. Wetland Protection .................................................................. 64 Introduction ................................................................................. 64 Wetland Regulation .......................................................................... 64 Wetland Acquisition .......................................................................... 65 Future